Merge pull request #3484 from Multiverse/fix/acf-locales

Allow locales folder to add and override acf messages

.github/workflows/generic.platform_uploads.yml

@@ -107,7 +107,7 @@ jobs:
         files: '["${{ github.workspace }}/${{ inputs.plugin_name }}-${{ steps.release-info.outputs.tag_name }}.jar"]'
         name: ${{ steps.release-info.outputs.tag_name }}
         changelog: ${{ steps.release-artifact.outputs.body }}
-        game_versions: 1.21.11, 1.21.10, 1.21.9, 1.21.8, 1.21.7, 1.21.6, 1.21.5, 1.21.4, 1.21.3, 1.21.2, 1.21.1, 1.21, 1.20.6, 1.20.5, 1.20.4, 1.20.3, 1.20.2, 1.20.1, 1.20, 1.19.4, 1.19.3, 1.19.2, 1.19.1, 1.19, 1.18.2
+        game_versions: 26.1.2, 26.1.1, 26.1, 1.21.11, 1.21.10, 1.21.9, 1.21.8, 1.21.7, 1.21.6, 1.21.5, 1.21.4, 1.21.3, 1.21.2, 1.21.1, 1.21, 1.20.6, 1.20.5, 1.20.4, 1.20.3, 1.20.2, 1.20.1, 1.20, 1.19.4, 1.19.3, 1.19.2, 1.19.1, 1.19, 1.18.2
         version_type: ${{ steps.parse-release-type.outputs.release_type }}
         loaders: bukkit, spigot, paper, purpur
         dependencies: ${{ inputs.modrinth_dependencies }}
@@ -121,7 +121,7 @@ jobs:
         changelog: ${{ steps.release-artifact.outputs.body }}
         changelog_type: markdown
         display_name: ${{ steps.release-info.outputs.tag_name }}
-        game_versions: 1.21.11, 1.21.10, 1.21.9, 1.21.8, 1.21.7, 1.21.6, 1.21.5, 1.21.4, 1.21.3, 1.21.2, 1.21.1, 1.21, 1.20.6, 1.20.5, 1.20.4, 1.20.3, 1.20.2, 1.20.1, 1.20, 1.19.4, 1.19.3, 1.19.2, 1.19.1, 1.19, 1.18.2
+        game_versions: 26.1.2, 26.1.1, 26.1, 1.21.11, 1.21.10, 1.21.9, 1.21.8, 1.21.7, 1.21.6, 1.21.5, 1.21.4, 1.21.3, 1.21.2, 1.21.1, 1.21, 1.20.6, 1.20.5, 1.20.4, 1.20.3, 1.20.2, 1.20.1, 1.20, 1.19.4, 1.19.3, 1.19.2, 1.19.1, 1.19, 1.18.2
         release_type: ${{ steps.parse-release-type.outputs.release_type }}
         project_relations: ${{ inputs.dbo_project_relations }}
         file_path: ${{ github.workspace }}/${{ inputs.plugin_name }}-${{ steps.release-info.outputs.tag_name }}.jar
@@ -136,5 +136,5 @@ jobs:
         channel: ${{ steps.parse-release-type.outputs.release_type }}
         files: '[{"path": "${{ github.workspace }}/${{ inputs.plugin_name }}-${{ steps.release-info.outputs.tag_name }}.jar", "platforms": ["PAPER"]}]'
         description: ${{ steps.release-artifact.outputs.body }}
-        platform_dependencies: '{"PAPER": ["1.18.2-1.21.11"]}'
+        platform_dependencies: '{"PAPER": ["1.18.2-26.1.2"]}'
         plugin_dependencies: ${{ inputs.hangar_plugin_dependencies }}

build.gradle

@@ -25,9 +25,9 @@ repositories {
 }
 
 configure(apiDependencies) {
-    serverApiVersion = '1.21.8-R0.1-SNAPSHOT'
+    serverApiVersion = '1.21.11-R0.1-SNAPSHOT'
     mockBukkitServerApiVersion = '1.21'
-    mockBukkitVersion = '4.84.0'
+    mockBukkitVersion = '4.110.0'
 }
 
 dependencies {

src/main/java/org/mvplugins/multiverse/core/MultiverseCore.java

@@ -126,6 +126,7 @@ public class MultiverseCore extends MultiverseModule {
         MultiverseCoreApi.shutdown();
         shutdownDependencyInjection();
         PluginServiceLocatorFactory.get().shutdown();
+        Logging.info("- Disabled");
         Logging.shutdown();
     }
 
@@ -225,11 +226,12 @@ public class MultiverseCore extends MultiverseModule {
      * Logs the enable message.
      */
     private void logEnableMessage() {
-        Logging.config("\u001B[32mVersion %s (API v%s) Enabled - By %s\u001B[39m",
+        Logging.config("\u001B[32mVersion %s (API v%s) Enabled - By %s\u001B[0m",
                 this.getDescription().getVersion(), getVersionAsNumber(), StringFormatter.joinAnd(getDescription().getAuthors()));
 
         if (configProvider.get().isShowingDonateMessage()) {
-            Logging.config("\u001B[32mLoving Multiverse-Core? Please consider supporting the project with a small donation: https://github.com/sponsors/Multiverse\u001B[39m");
+            Logging.config("\u001B[32mLoving Multiverse-Core? Please consider supporting the project with a " +
+                    "small donation: https://github.com/sponsors/Multiverse\u001B[0m");
         }
     }
 

src/main/java/org/mvplugins/multiverse/core/MultiverseCoreApi.java

@@ -24,7 +24,7 @@ import java.util.function.Consumer;
 /**
  * Provides access to the MultiverseCore API.
  */
-public class MultiverseCoreApi {
+public final class MultiverseCoreApi {
 
     private static MultiverseCoreApi instance;
     private static final List<Consumer<MultiverseCoreApi>> whenLoadedCallbacks = new ArrayList<>();

src/main/java/org/mvplugins/multiverse/core/PlaceholderExpansionHook.java

@@ -1,6 +1,7 @@
 package org.mvplugins.multiverse.core;
 
 import com.google.common.collect.Lists;
+import io.vavr.control.Option;
 import jakarta.annotation.PostConstruct;
 import jakarta.inject.Inject;
 import me.clip.placeholderapi.expansion.PlaceholderExpansion;
@@ -12,11 +13,13 @@ import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.jvnet.hk2.annotations.Service;
 
+import org.mvplugins.multiverse.core.config.CoreConfig;
 import org.mvplugins.multiverse.core.economy.MVEconomist;
 import org.mvplugins.multiverse.core.utils.MinecraftTimeFormatter;
 import org.mvplugins.multiverse.core.utils.REPatterns;
 import org.mvplugins.multiverse.core.utils.StringFormatter;
 import org.mvplugins.multiverse.core.world.LoadedMultiverseWorld;
+import org.mvplugins.multiverse.core.world.MultiverseWorld;
 import org.mvplugins.multiverse.core.world.WorldManager;
 
 import java.util.List;
@@ -26,12 +29,17 @@ import java.util.Locale;
 final class PlaceholderExpansionHook extends PlaceholderExpansion {
 
     private final MultiverseCore plugin;
+    private final CoreConfig coreConfig;
     private final WorldManager worldManager;
     private final MVEconomist economist;
 
     @Inject
-    public PlaceholderExpansionHook(MultiverseCore plugin, WorldManager worldManager, MVEconomist economist) {
+    public PlaceholderExpansionHook(@NotNull MultiverseCore plugin,
+                                    @NotNull CoreConfig coreConfig,
+                                    @NotNull WorldManager worldManager,
+                                    @NotNull MVEconomist economist) {
         this.plugin = plugin;
+        this.coreConfig = coreConfig;
         this.worldManager = worldManager;
         this.economist = economist;
     }
@@ -42,6 +50,13 @@ final class PlaceholderExpansionHook extends PlaceholderExpansion {
         return super.register();
     }
 
+    @Override
+    public void warning(String msg) {
+        if (coreConfig.getWarnInvalidPapiFormat()) {
+            super.warning(msg);
+        }
+    }
+
     @Override
     public @NotNull String getIdentifier() {
         return "multiverse-core";
@@ -80,136 +95,115 @@ final class PlaceholderExpansionHook extends PlaceholderExpansion {
             return null;
         }
 
-        final var placeholder = paramsArray.remove(0);
+        final var placeholder = paramsArray.remove(0).toLowerCase(Locale.ENGLISH);
 
-        String worldName = parseWorldName(offlinePlayer, paramsArray);
-        if (worldName == null) return null;
-
-        return worldManager.getLoadedWorld(worldName)
-                .onEmpty(() -> warning("Multiverse World not found: " + worldName))
-                .map(world -> getWorldPlaceHolderValue(placeholder, paramsArray, world))
-                .getOrNull();
+        return parseWorldName(offlinePlayer, paramsArray)
+                .flatMap(worldName -> worldManager.getWorld(worldName)
+                    .onEmpty(() -> warning("Multiverse World not found: " + worldName)))
+                .flatMap(world -> world.asLoadedWorld()
+                        .flatMap(loadedWorld -> getLoadedWorldPlaceHolderValue(placeholder, paramsArray, loadedWorld))
+                        .orElse(() -> getWorldPlaceHolderValue(placeholder, paramsArray, world)))
+                .getOrElse(() -> coreConfig.getInvalidPapiFormatReturnsBlank() ? "" : null);
     }
 
-    private @Nullable String parseWorldName(OfflinePlayer offlinePlayer, List<String> paramsArray) {
+    private @NotNull Option<String> parseWorldName(OfflinePlayer offlinePlayer, List<String> paramsArray) {
         // No world defined, get from player
         if (paramsArray.isEmpty()) {
             if (offlinePlayer instanceof Player player) {
-                return player.getWorld().getName();
+                return Option.of(player.getWorld().getName());
             } else {
                 warning("You must specify a world name for non-player placeholders");
-                return null;
+                return Option.none();
             }
         }
 
         // Try get from params
         String paramWorldName = paramsArray.get(paramsArray.size() - 1);
-        if (worldManager.isLoadedWorld(paramWorldName)) {
+        if (worldManager.isWorld(paramWorldName)) {
             paramsArray.remove(paramsArray.size() - 1);
-            return paramWorldName;
+            return Option.of(paramWorldName);
         }
 
         // Param not a world, fallback to player
         if (offlinePlayer instanceof Player player) {
-            return player.getWorld().getName();
+            return Option.of(player.getWorld().getName());
         }
         warning("Multiverse World not found: " + paramWorldName);
-        return null;
+        return Option.none();
     }
 
-    private @Nullable String getWorldPlaceHolderValue(@NotNull String placeholder,
-                                                      @NotNull List<String> placeholderParams,
-                                                      @NotNull LoadedMultiverseWorld world) {
-        // Switch to find what specific placeholder we want
-        switch (placeholder.toLowerCase(Locale.ENGLISH)) {
-            case "alias" -> {
-                return world.getAliasOrName();
+    private @NotNull Option<String> getWorldPlaceHolderValue(@NotNull String placeholder,
+                                                             @NotNull List<String> placeholderParams,
+                                                             @NotNull MultiverseWorld world) {
+        return Option.of(switch (placeholder) {
+            case "alias" -> world.getAliasOrName();
+            case "animalspawn" -> String.valueOf(world.getEntitySpawnConfig()
+                    .getSpawnCategoryConfig(SpawnCategory.ANIMAL)
+                    .isSpawn());
+            case "autoheal" -> String.valueOf(world.getAutoHeal());
+            case "blacklist" -> String.join(", ", world.getWorldBlacklist());
+            case "currency" -> String.valueOf(world.getCurrency());
+            case "difficulty" -> world.getDifficulty().toString();
+            case "entryfee" -> economist.formatPrice(world.getPrice(), world.getCurrency());
+            case "environment" -> world.getEnvironment().toString().toLowerCase();
+            case "flight" -> String.valueOf(world.isAllowFlight());
+            case "gamemode" -> world.getGameMode().toString().toLowerCase();
+            case "generator" -> world.getGenerator();
+            case "hunger" -> String.valueOf(world.isHunger());
+            case "isloaded" -> String.valueOf(world.isLoaded());
+            case "key" -> String.valueOf(world.getKey());
+            case "meta" -> {
+                if (placeholderParams.isEmpty()) {
+                    warning("No meta key specified.");
+                    yield null;
+                }
+                String metaKey = String.join("_", placeholderParams);
+                yield world.getMeta(metaKey)
+                        .getOrElse(() -> {
+                            warning("Meta key '" + metaKey + "' not found for world '" + world.getName() + "'.");
+                            return null;
+                        });
             }
-            case "animalspawn" -> {
-                return String.valueOf(world.getEntitySpawnConfig().getSpawnCategoryConfig(SpawnCategory.ANIMAL).isSpawn());
+            case "monstersspawn" -> String.valueOf(world.getEntitySpawnConfig()
+                    .getSpawnCategoryConfig(SpawnCategory.MONSTER)
+                    .isSpawn());
+            case "name" -> world.getName();
+            case "playerlimit" -> String.valueOf(world.getPlayerLimit());
+            case "price" -> String.valueOf(world.getPrice());
+            case "pvp" -> String.valueOf(world.getPvp());
+            case "seed" -> String.valueOf(world.getSeed());
+            case "weather" -> String.valueOf(world.isAllowWeather());
+            case "playercount", "time", "type" -> {
+                warning("Placeholder '" + placeholder + "' is only available for loaded worlds.");
+                yield null;
             }
-            case "autoheal" -> {
-                return String.valueOf(world.getAutoHeal());
-            }
-            case "blacklist" -> {
-                return String.join(", ", world.getWorldBlacklist());
-            }
-            case "currency" -> {
-                return String.valueOf(world.getCurrency());
-            }
-            case "difficulty" -> {
-                return world.getDifficulty().toString();
-            }
-            case "entryfee" -> {
-                return economist.formatPrice(world.getPrice(), world.getCurrency());
-            }
-            case "environment" -> {
-                return world.getEnvironment().toString().toLowerCase();
-            }
-            case "flight" -> {
-                return String.valueOf(world.isAllowFlight());
-            }
-            case "gamemode" -> {
-                return world.getGameMode().toString().toLowerCase();
-            }
-            case "generator" -> {
-                return world.getGenerator();
-            }
-            case "hunger" -> {
-                return String.valueOf(world.isHunger());
-            }
-            case "monstersspawn" -> {
-                return String.valueOf(world.getEntitySpawnConfig().getSpawnCategoryConfig(SpawnCategory.MONSTER).isSpawn());
-            }
-            case "name" -> {
-                return world.getName();
-            }
-            case "playercount" -> {
-                return String.valueOf(world.getBukkitWorld()
-                        .map(World::getPlayers)
-                        .map(List::size)
-                        .getOrElse(-1));
-            }
-            case "playerlimit" -> {
-                return String.valueOf(world.getPlayerLimit());
-            }
-            case "price" -> {
-                return String.valueOf(world.getPrice());
-            }
-            case "pvp" -> {
-                return String.valueOf(world.getPvp());
-            }
-            case "seed" -> {
-                return String.valueOf(world.getSeed());
+            default -> {
+                warning("Unknown Placeholder: " + placeholder);
+                yield null;
             }
+        });
+    }
+
+    private @NotNull Option<String> getLoadedWorldPlaceHolderValue(@NotNull String placeholder,
+                                                                   @NotNull List<String> placeholderParams,
+                                                                   @NotNull LoadedMultiverseWorld world) {
+        return Option.of(switch (placeholder) {
+            case "playercount" -> String.valueOf(world.getBukkitWorld()
+                    .map(World::getPlayers)
+                    .map(List::size)
+                    .getOrElse(-1));
             case "time" -> {
                 String timeFormat = !placeholderParams.isEmpty() ? placeholderParams.get(0) : "";
                 long time = world.getBukkitWorld().map(World::getTime).getOrElse(0L);
-                switch (timeFormat) {
-                    case "" -> {
-                        return String.valueOf(time);
-                    }
-                    case "12h" -> {
-                        return MinecraftTimeFormatter.format12h(time);
-                    }
-                    case "24h" -> {
-                        return MinecraftTimeFormatter.format24h(time);
-                    }
-                    default -> {
-                        return MinecraftTimeFormatter.formatTime(time, timeFormat);
-                    }
-                }
+                yield switch (timeFormat) {
+                    case "" -> String.valueOf(time);
+                    case "12h" -> MinecraftTimeFormatter.format12h(time);
+                    case "24h" -> MinecraftTimeFormatter.format24h(time);
+                    default -> MinecraftTimeFormatter.formatTime(time, timeFormat);
+                };
             }
-            case "type" -> {
-                return world.getBukkitWorld().map(World::getWorldType).map(Enum::name).getOrElse("null");
-            }
-            case "weather" -> {
-                return String.valueOf(world.isAllowWeather());
-            }
-            default -> {
-                warning("Unknown placeholder: " + placeholder);
-                return null;
-            }
-        }
+            case "type" -> world.getBukkitWorld().map(World::getWorldType).map(Enum::name).getOrElse("null");
+            default -> null;
+        });
     }
 }

src/main/java/org/mvplugins/multiverse/core/command/MVCommandCompletionFilters.java

@@ -0,0 +1,60 @@
+package org.mvplugins.multiverse.core.command;
+
+import co.aikar.commands.CommandCompletionContext;
+import co.aikar.commands.CommandCompletionFilter;
+import co.aikar.commands.apachecommonslang.ApacheCommonsLangUtil;
+import org.jetbrains.annotations.ApiStatus;
+
+import java.util.Locale;
+
+/**
+ * Utility filters for command completion matching.
+ *
+ * @since 5.7
+ */
+@ApiStatus.AvailableSince("5.7")
+public final class MVCommandCompletionFilters {
+
+    /**
+     * Matches namespaced keys (for example, {@code minecraft:stone}) using namespace-aware checks.
+     * <p>
+     * This filter accepts completions that:
+     * <ul>
+     *     <li>start with the current input,</li>
+     *     <li>have a namespace starting with the input, or</li>
+     *     <li>have a key value containing the input.</li>
+     * </ul>
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static final CommandCompletionFilter NAMESPACED_KEY = (context, completion) -> {
+        String[] split = completion.split(":", 2);
+        if (split.length < 2) {
+            return ApacheCommonsLangUtil.startsWithIgnoreCase(completion, context.getInput());
+        }
+        String lowerCase = context.getInput().toLowerCase(Locale.ROOT);
+        return ApacheCommonsLangUtil.startsWithIgnoreCase(completion, context.getInput())
+                || split[0].toLowerCase(Locale.ROOT).startsWith(lowerCase)
+                || split[1].toLowerCase(Locale.ROOT).contains(lowerCase);
+    };
+
+    /**
+     * Gets the namespaced-key completion filter with a generic type-safe signature.
+     * Use this method instead of {@link MVCommandCompletionFilters#NAMESPACED_KEY}
+     * to avoid raw type unchecked warnings.
+     *
+     * @param <C> completion context type
+     * @return the namespaced key filter
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static <C extends CommandCompletionContext> CommandCompletionFilter<C> namespacedKey() {
+        return NAMESPACED_KEY;
+    }
+
+    private MVCommandCompletionFilters() {
+        throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
+    }
+}

src/main/java/org/mvplugins/multiverse/core/command/MVCommandCompletions.java

@@ -11,6 +11,7 @@ import java.util.Map;
 import java.util.stream.Collectors;
 
 import co.aikar.commands.BukkitCommandCompletionContext;
+import co.aikar.commands.CommandCompletionFilter;
 import co.aikar.commands.CommandIssuer;
 import co.aikar.commands.PaperCommandCompletions;
 import co.aikar.commands.RegisteredCommand;
@@ -52,8 +53,9 @@ import org.mvplugins.multiverse.core.world.MultiverseWorld;
 import org.mvplugins.multiverse.core.world.WorldManager;
 import org.mvplugins.multiverse.core.world.generators.GeneratorPlugin;
 import org.mvplugins.multiverse.core.world.generators.GeneratorProvider;
+import org.mvplugins.multiverse.core.world.helpers.PotentialWorldFinder;
 
-import static org.mvplugins.multiverse.core.utils.StringFormatter.addonToCommaSeperated;
+import static org.mvplugins.multiverse.core.utils.StringFormatter.addOnToCommaSeparated;
 
 @Service
 public class MVCommandCompletions extends PaperCommandCompletions {
@@ -65,6 +67,7 @@ public class MVCommandCompletions extends PaperCommandCompletions {
     private final CorePermissionsChecker corePermissionsChecker;
     private final AnchorManager anchorManager;
     private final GeneratorProvider generatorProvider;
+    private final PotentialWorldFinder potentialWorldFinder;
 
     @Inject
     MVCommandCompletions(
@@ -74,7 +77,8 @@ public class MVCommandCompletions extends PaperCommandCompletions {
             @NotNull CoreConfig config,
             @NotNull CorePermissionsChecker corePermissionsChecker,
             @NotNull AnchorManager anchorManager,
-            @NotNull GeneratorProvider generatorProvider
+            @NotNull GeneratorProvider generatorProvider,
+            @NotNull PotentialWorldFinder potentialWorldFinder
     ) {
         super(mvCommandManager);
         this.commandManager = mvCommandManager;
@@ -84,27 +88,29 @@ public class MVCommandCompletions extends PaperCommandCompletions {
         this.corePermissionsChecker = corePermissionsChecker;
         this.anchorManager = anchorManager;
         this.generatorProvider = generatorProvider;
+        this.potentialWorldFinder = potentialWorldFinder;
 
-        registerAsyncCompletion("anchornames", this::suggestAnchorNames);
+        registerAsyncCompletion("anchornames", this::suggestAnchorNames, CommandCompletionFilter.contains());
         registerAsyncCompletion("commands", this::suggestCommands);
         registerAsyncCompletion("destinations", this::suggestDestinations);
         registerStaticCompletion("difficulties", suggestEnums(Difficulty.class));
         registerStaticCompletion("environments", List.of("normal", "nether", "the_end")); // Don't tab complete the "custom" environment
         registerAsyncCompletion("flags", this::suggestFlags);
         registerStaticCompletion("gamemodes", suggestEnums(GameMode.class));
-        registerStaticCompletion("gamerules", this::suggestGamerules);
+        registerStaticCompletion("gamerules", this::suggestGamerules, MVCommandCompletionFilters.namespacedKey());
         registerAsyncCompletion("gamerulesvalues", this::suggestGamerulesValues);
-        registerAsyncCompletion("generatorplugins", this::suggestGeneratorPlugins);
-        registerStaticCompletion("materials", suggestEnums(Material.class));
-        registerStaticCompletion("mvconfigs", config.getStringPropertyHandle().getAllPropertyNames());
+        registerAsyncCompletion("generatorplugins", this::suggestGeneratorPlugins, CommandCompletionFilter.contains());
+        registerStaticCompletion("materials", suggestEnums(Material.class), CommandCompletionFilter.contains());
+        registerStaticCompletion("mvconfigs", config.getStringPropertyHandle().getAllPropertyNames(), CommandCompletionFilter.contains());
         registerAsyncCompletion("mvconfigvalues", this::suggestMVConfigValues);
-        registerAsyncCompletion("mvworlds", this::suggestMVWorlds);
-        registerAsyncCompletion("mvworldpropsname", this::suggestMVWorldPropsName);
+        registerAsyncCompletion("mvworlds", this::suggestMVWorlds, MVCommandCompletionFilters.namespacedKey());
+        registerAsyncCompletion("mvworldmetakey", this::suggestMVWorldMetaKey, CommandCompletionFilter.contains());
+        registerAsyncCompletion("mvworldpropsname", this::suggestMVWorldPropsName, CommandCompletionFilter.contains());
         registerAsyncCompletion("mvworldpropsvalue", this::suggestMVWorldPropsValue);
-        registerCompletion("playersarray", this::suggestPlayersArray); // getting online players cannot be async
+        registerCompletion("playersarray", this::suggestPlayersArray, CommandCompletionFilter.contains()); // getting online players cannot be async
         registerStaticCompletion("propsmodifyaction", suggestEnums(PropertyModifyAction.class));
         registerStaticCompletion("spawncategories", suggestEnums(SpawnCategory.class));
-        registerAsyncCompletion("spawncategorypropsname", this::suggestSpawnCategoryPropsName);
+        registerAsyncCompletion("spawncategorypropsname", this::suggestSpawnCategoryPropsName, CommandCompletionFilter.contains());
         registerAsyncCompletion("spawncategorypropsvalue", this::suggestSpawnCategoryPropsValue);
 
         setDefaultCompletion("destinations", DestinationInstance.class);
@@ -163,7 +169,7 @@ public class MVCommandCompletions extends PaperCommandCompletions {
             }
         }
         if (context.hasConfig("multiple")) {
-            return addonToCommaSeperated(context.getInput(), handler.getCompletions(context));
+            return addOnToCommaSeparated(context.getInput(), handler.getCompletions(context));
         }
         return handler.getCompletions(context);
     }
@@ -297,13 +303,20 @@ public class MVCommandCompletions extends PaperCommandCompletions {
                         .toList();
             }
             case "potential" -> {
-                return worldManager.getPotentialWorlds();
+                return potentialWorldFinder.findPotentialWorlds();
             }
         }
         Logging.severe("Invalid MVWorld scope: " + scope);
         return Collections.emptyList();
     }
 
+    private Collection<String> suggestMVWorldMetaKey(BukkitCommandCompletionContext context) {
+        return Try.of(() -> context.getContextValue(MultiverseWorld.class))
+                .map(MultiverseWorld::getAllMeta)
+                .map(Map::keySet)
+                .getOrElse(Collections.emptySet());
+    }
+
     private Collection<String> suggestMVWorldPropsName(BukkitCommandCompletionContext context) {
         return Try.of(() -> {
             MultiverseWorld world = context.getContextValue(MultiverseWorldValue.class).value();
@@ -334,7 +347,7 @@ public class MVCommandCompletions extends PaperCommandCompletions {
                 matchedPlayers.add(name);
             }
         }
-        return addonToCommaSeperated(context.getInput(), matchedPlayers);
+        return addOnToCommaSeparated(context.getInput(), matchedPlayers);
     }
 
     private Collection<String> suggestSpawnCategoryPropsName(BukkitCommandCompletionContext context) {

src/main/java/org/mvplugins/multiverse/core/command/MVCommandContexts.java

@@ -42,6 +42,7 @@ import org.mvplugins.multiverse.core.exceptions.command.MVInvalidCommandArgument
 import org.mvplugins.multiverse.core.locale.message.Message;
 import org.mvplugins.multiverse.core.utils.PlayerFinder;
 import org.mvplugins.multiverse.core.utils.REPatterns;
+import org.mvplugins.multiverse.core.utils.tick.TickDuration;
 import org.mvplugins.multiverse.core.world.LoadedMultiverseWorld;
 import org.mvplugins.multiverse.core.world.MultiverseWorld;
 import org.mvplugins.multiverse.core.world.WorldManager;
@@ -93,6 +94,7 @@ public class MVCommandContexts extends PaperCommandContexts {
         registerIssuerAwareContext(PlayerArrayValue.class, playerArrayContextBuilder().generateContext(PlayerArrayValue::new));
         registerIssuerAwareContext(PlayerLocation.class, this::parsePlayerLocation);
         registerContext(SpawnCategory[].class, this::parseSpawnCategories);
+        registerContext(TickDuration.class, this::parseTickDuration);
     }
 
     private MVCommandIssuer parseMVCommandIssuer(BukkitCommandExecutionContext context) {
@@ -393,4 +395,13 @@ public class MVCommandContexts extends PaperCommandContexts {
         }
         return categories.toArray(new SpawnCategory[0]);
     }
+
+    private TickDuration parseTickDuration(BukkitCommandExecutionContext context) {
+        String arg = context.popFirstArg();
+        return TickDuration.parseString(arg)
+                .getOrElseThrow(failure ->
+                        new InvalidCommandArgument("Invalid time duration format: \"" +arg + "\". Use a number " +
+                                "followed by an optional suffix (s for seconds, d for game days) or just a number " +
+                                "for ticks. Examples: 100, 5s, 2d"));
+    }
 }

src/main/java/org/mvplugins/multiverse/core/command/MVCommandManager.java

@@ -62,7 +62,6 @@ public class MVCommandManager extends PaperCommandManager {
         this.config = config;
         this.pluginLocales = new PluginLocales(this);
         this.locales = this.pluginLocales;
-        this.pluginLocales.loadLanguages();
 
         MVCommandConditions.load(this, worldManager, worldNameChecker);
         this.enableUnstableAPI("help");

src/main/java/org/mvplugins/multiverse/core/command/flag/CommandValueFlag.java

@@ -5,8 +5,10 @@ import java.util.Collection;
 import java.util.List;
 import java.util.Locale;
 import java.util.function.Function;
+import java.util.function.Supplier;
 
 import co.aikar.commands.InvalidCommandArgument;
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
@@ -40,34 +42,34 @@ public class CommandValueFlag<T> extends CommandFlag {
 
     private final Class<T> type;
     private final boolean optional;
-    private final T defaultValue;
+    private final Supplier<? extends T> defaultValueSupplier;
     private final Function<String, T> context;
     private final Function<String, Collection<String>>  completion;
 
     /**
      * Creates a new flag.
      *
-     * @param key               The key for the new flag.
-     * @param aliases           The aliases that also refer to this flag.
-     * @param type              The type of the value.
-     * @param optional          Allow for flag without value.
-     * @param defaultValue      The default value if optional is true and user does not specify a value.
-     * @param context           Function to parse string into value type.
-     * @param completion        Function to get completion for this flag.
+     * @param key                   The key for the new flag.
+     * @param aliases               The aliases that also refer to this flag.
+     * @param type                  The type of the value.
+     * @param optional              Allow for flag without value.
+     * @param defaultValueSupplier  The default value if optional is true and user does not specify a value.
+     * @param context               Function to parse string into value type.
+     * @param completion            Function to get completion for this flag.
      */
     protected CommandValueFlag(
             @NotNull String key,
             @NotNull List<String> aliases,
             @NotNull Class<T> type,
             boolean optional,
-            @Nullable T defaultValue,
+            @Nullable Supplier<? extends T> defaultValueSupplier,
             @Nullable Function<String, T> context,
             @Nullable Function<String, Collection<String>>  completion
     ) {
         super(key, aliases);
         this.type = type;
         this.optional = optional;
-        this.defaultValue = defaultValue;
+        this.defaultValueSupplier = defaultValueSupplier;
         this.context = context;
         this.completion = completion;
     }
@@ -96,7 +98,7 @@ public class CommandValueFlag<T> extends CommandFlag {
      * @return The default value.
      */
     public @Nullable T getDefaultValue() {
-        return defaultValue;
+        return defaultValueSupplier == null ? null : defaultValueSupplier.get();
     }
 
     /**
@@ -126,7 +128,7 @@ public class CommandValueFlag<T> extends CommandFlag {
     public static class Builder<T, S extends Builder<T, S>> extends CommandFlag.Builder<S> {
         protected final Class<T> type;
         protected boolean optional = false;
-        protected T defaultValue = null;
+        protected Supplier<? extends T> defaultValueSupplier = null;
         protected Function<String, T> context = null;
         protected Function<String, Collection<String>> completion = null;
 
@@ -158,7 +160,21 @@ public class CommandValueFlag<T> extends CommandFlag {
          * @return The builder.
          */
         public @NotNull S defaultValue(@NotNull T defaultValue) {
-            this.defaultValue = defaultValue;
+            return defaultValue(() -> defaultValue);
+        }
+
+        /**
+         * Set the default value supplier. Used if optional is true and user does not specify a value.
+         * Supplier is only called when command is executed with the flag is present in input.
+         *
+         * @param defaultValueSupplier The default value supplier
+         * @return The builder
+         *
+         * @since 5.7
+         */
+        @ApiStatus.AvailableSince("5.7")
+        public @NotNull S defaultValue(@NotNull Supplier<? extends T> defaultValueSupplier) {
+            this.defaultValueSupplier = defaultValueSupplier;
             return (S) this;
         }
 
@@ -194,7 +210,7 @@ public class CommandValueFlag<T> extends CommandFlag {
             if (context == null && !String.class.equals(type)) {
                 throw new IllegalStateException("Context is required for non-string value flags");
             }
-            return new CommandValueFlag<>(key, aliases, type, optional, defaultValue, context, completion);
+            return new CommandValueFlag<>(key, aliases, type, optional, defaultValueSupplier, context, completion);
         }
     }
 
@@ -207,7 +223,7 @@ public class CommandValueFlag<T> extends CommandFlag {
     public static class EnumBuilder<T extends Enum<T>, S extends EnumBuilder<T, S>> extends CommandFlag.Builder<S> {
         protected final Class<T> type;
         protected boolean optional = false;
-        protected T defaultValue = null;
+        protected Supplier<? extends T> defaultValueSupplier = null;
         protected Function<String, T> context = null;
         protected Function<String, Collection<String>>  completion = null;
 
@@ -253,7 +269,21 @@ public class CommandValueFlag<T> extends CommandFlag {
          * @return The builder.
          */
         public @NotNull S defaultValue(@NotNull T defaultValue) {
-            this.defaultValue = defaultValue;
+            return defaultValue(() -> defaultValue);
+        }
+
+        /**
+         * Set the default value to supply. Used if optional is true and user does not specify a value.
+         * Supplier is only called when command is executed with the flag is present in input.
+         *
+         * @param defaultValueSupplier The default value supplier.
+         * @return The builder.
+         *
+         * @since 5.7
+         */
+        @ApiStatus.AvailableSince("5.7")
+        public @NotNull S defaultValue(@NotNull Supplier<? extends T> defaultValueSupplier) {
+            this.defaultValueSupplier = defaultValueSupplier;
             return (S) this;
         }
 
@@ -264,7 +294,7 @@ public class CommandValueFlag<T> extends CommandFlag {
          */
         @Override
         public @NotNull CommandValueFlag<T> build() {
-            return new CommandValueFlag<>(key, aliases, type, optional, defaultValue, context, completion);
+            return new CommandValueFlag<>(key, aliases, type, optional, defaultValueSupplier, context, completion);
         }
     }
 }

src/main/java/org/mvplugins/multiverse/core/command/flags/RemovePlayerDestinationFlags.java

@@ -0,0 +1,65 @@
+package org.mvplugins.multiverse.core.command.flags;
+
+import co.aikar.commands.InvalidCommandArgument;
+import jakarta.inject.Inject;
+import org.bukkit.Bukkit;
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.NotNull;
+import org.jvnet.hk2.annotations.Service;
+import org.mvplugins.multiverse.core.command.flag.CommandFlagsManager;
+import org.mvplugins.multiverse.core.command.flag.CommandValueFlag;
+import org.mvplugins.multiverse.core.command.flag.FlagBuilder;
+import org.mvplugins.multiverse.core.destination.DestinationInstance;
+import org.mvplugins.multiverse.core.destination.DestinationsProvider;
+import org.mvplugins.multiverse.core.destination.core.WorldDestination;
+import org.mvplugins.multiverse.core.exceptions.command.MVInvalidCommandArgument;
+import org.mvplugins.multiverse.core.world.WorldManager;
+
+@ApiStatus.AvailableSince("5.7")
+@Service
+public class RemovePlayerDestinationFlags extends FlagBuilder {
+
+    public static final String NAME = "removeplayer";
+
+    private WorldManager worldManager;
+    private DestinationsProvider destinationsProvider;
+    private WorldDestination worldDestination;
+
+    protected RemovePlayerDestinationFlags(
+            @NotNull String name,
+            @NotNull CommandFlagsManager flagsManager,
+            @NotNull WorldManager worldManager,
+            @NotNull DestinationsProvider destinationsProvider,
+            @NotNull WorldDestination worldDestination
+    ) {
+        super(name, flagsManager);
+        this.worldManager = worldManager;
+        this.destinationsProvider = destinationsProvider;
+        this.worldDestination = worldDestination;
+    }
+
+    @Inject
+    private RemovePlayerDestinationFlags(
+            @NotNull CommandFlagsManager flagsManager,
+            @NotNull WorldManager worldManager,
+            @NotNull DestinationsProvider destinationsProvider,
+            @NotNull WorldDestination worldDestination
+    ) {
+        super(NAME, flagsManager);
+        this.destinationsProvider = destinationsProvider;
+        this.worldManager = worldManager;
+        this.worldDestination = worldDestination;
+    }
+
+    public final CommandValueFlag<DestinationInstance> removePlayers = flag(CommandValueFlag.builder("--remove-players", DestinationInstance.class)
+            .addAlias("-r")
+            .defaultValue(() -> worldManager.getDefaultWorld()
+                    .map(defaultWorld -> worldDestination.fromWorld(defaultWorld))
+                    .getOrElseThrow(() -> new InvalidCommandArgument("No default world found, so the --remove-players flag requires a destination argument."))) //TODO: locale
+            .completion(input -> destinationsProvider.suggestDestinationStrings(Bukkit.getConsoleSender(), input))
+            .context(input -> destinationsProvider.parseDestination(input)
+                    .getOrThrow(failure ->
+                            MVInvalidCommandArgument.of(failure.getFailureMessage())))
+            .optional()
+            .build());
+}

src/main/java/org/mvplugins/multiverse/core/command/flags/RemovePlayerFlags.java

@@ -1,12 +1,19 @@
 package org.mvplugins.multiverse.core.command.flags;
 
 import jakarta.inject.Inject;
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 import org.jvnet.hk2.annotations.Service;
 import org.mvplugins.multiverse.core.command.flag.CommandFlag;
 import org.mvplugins.multiverse.core.command.flag.CommandFlagsManager;
 import org.mvplugins.multiverse.core.command.flag.FlagBuilder;
 
+/**
+ * @deprecated The --remove-players flag is being removed in favor of a more flexible system that allows for specifying
+ * a destination for players to be teleported to when a world is unloaded. See {@link RemovePlayerDestinationFlags}.
+ */
+@Deprecated(forRemoval = true, since = "5.7")
+@ApiStatus.ScheduledForRemoval(inVersion = "6.0")
 @Service
 public class RemovePlayerFlags extends FlagBuilder {
 

src/main/java/org/mvplugins/multiverse/core/commands/CloneCommand.java

@@ -20,7 +20,7 @@ import org.mvplugins.multiverse.core.command.flag.FlagBuilder;
 import org.mvplugins.multiverse.core.command.flag.ParsedCommandFlags;
 import org.mvplugins.multiverse.core.locale.MVCorei18n;
 import org.mvplugins.multiverse.core.locale.message.MessageReplacement.Replace;
-import org.mvplugins.multiverse.core.world.LoadedMultiverseWorld;
+import org.mvplugins.multiverse.core.world.MultiverseWorld;
 import org.mvplugins.multiverse.core.world.WorldManager;
 import org.mvplugins.multiverse.core.world.options.CloneWorldOptions;
 
@@ -48,7 +48,7 @@ class CloneCommand extends CoreCommand {
 
             @Syntax("<world>")
             @Description("{@@mv-core.clone.world.description}")
-            LoadedMultiverseWorld world,
+            MultiverseWorld world,
 
             @Syntax("<new-world-name>")
             @Description("{@@mv-core.clone.newWorld.description}")
@@ -114,7 +114,7 @@ class CloneCommand extends CoreCommand {
 
         @Override
         @CommandAlias("mvcl|mvclone")
-        void onCloneCommand(MVCommandIssuer issuer, LoadedMultiverseWorld world, String newWorldName, String[] flags) {
+        void onCloneCommand(MVCommandIssuer issuer, MultiverseWorld world, String newWorldName, String[] flags) {
             super.onCloneCommand(issuer, world, newWorldName, flags);
         }
     }

src/main/java/org/mvplugins/multiverse/core/commands/CreateCommand.java

@@ -11,6 +11,7 @@ import co.aikar.commands.annotation.Optional;
 import co.aikar.commands.annotation.Subcommand;
 import co.aikar.commands.annotation.Syntax;
 import com.dumptruckman.minecraft.util.Logging;
+import io.vavr.control.Try;
 import jakarta.inject.Inject;
 import org.bukkit.World;
 import org.bukkit.WorldType;
@@ -19,14 +20,16 @@ import org.jvnet.hk2.annotations.Service;
 
 import org.mvplugins.multiverse.core.command.LegacyAliasCommand;
 import org.mvplugins.multiverse.core.command.MVCommandIssuer;
-import org.mvplugins.multiverse.core.command.MVCommandManager;
 import org.mvplugins.multiverse.core.command.flag.CommandFlag;
 import org.mvplugins.multiverse.core.command.flag.CommandFlagsManager;
 import org.mvplugins.multiverse.core.command.flag.CommandValueFlag;
 import org.mvplugins.multiverse.core.command.flag.FlagBuilder;
 import org.mvplugins.multiverse.core.command.flag.ParsedCommandFlags;
+import org.mvplugins.multiverse.core.exceptions.command.MVInvalidCommandArgument;
 import org.mvplugins.multiverse.core.locale.MVCorei18n;
 import org.mvplugins.multiverse.core.locale.message.MessageReplacement.Replace;
+import org.mvplugins.multiverse.core.utils.StringFormatter;
+import org.mvplugins.multiverse.core.utils.position.EntityPosition;
 import org.mvplugins.multiverse.core.utils.result.Attempt.Failure;
 import org.mvplugins.multiverse.core.world.LoadedMultiverseWorld;
 import org.mvplugins.multiverse.core.world.WorldManager;
@@ -52,8 +55,9 @@ class CreateCommand extends CoreCommand {
     @Subcommand("create")
     @CommandPermission("multiverse.core.create")
     @CommandCompletion("@empty @environments @flags:groupName=" + Flags.NAME)
-    @Syntax("<name> <environment> [--seed <seed> --generator <generator[:id]> --world-type <worldtype> --adjust-spawn "
-            + "--no-structures --biome <biome>]")
+    @Syntax("<name> <environment> [--seed <seed> --generator <generator[:id]> --world-type <worldtype> " +
+            "--adjust-spawn --no-structures --generate-bonus-chest --force-spawn-position <x,y,z:pitch:yaw> " +
+            "--biome <biome> --generator-settings <json-settings> --properties <prop1=value1,prop2=value2,...>]")
     @Description("{@@mv-core.create.description}")
     void onCreateCommand(
             MVCommandIssuer issuer,
@@ -67,8 +71,9 @@ class CreateCommand extends CoreCommand {
             World.Environment environment,
 
             @Optional
-            @Syntax("[--seed <seed> --generator <generator[:id]> --world-type <worldtype> --adjust-spawn "
-                    + "--no-structures --biome <biome>]")
+            @Syntax("[--seed <seed> --generator <generator[:id]> --world-type <worldtype> --adjust-spawn " +
+                    "--no-structures --generate-bonus-chest --force-spawn-position <x,y,z:pitch:yaw> --biome <biome> " +
+                    "--generator-settings <json-settings> --properties <prop1=value1,prop2=value2,...>]")
             @Description("{@@mv-core.create.flags.description}")
             String[] flagArray) {
         ParsedCommandFlags parsedFlags = flags.parse(flagArray);
@@ -78,14 +83,17 @@ class CreateCommand extends CoreCommand {
         issuer.sendInfo(MVCorei18n.CREATE_LOADING);
 
         worldManager.createWorld(CreateWorldOptions.worldName(worldName)
-                .biome(parsedFlags.flagValue(flags.biome, ""))
-                .environment(environment)
-                .seed(parsedFlags.flagValue(flags.seed))
-                .worldType(parsedFlags.flagValue(flags.worldType, WorldType.NORMAL))
-                .useSpawnAdjust(!parsedFlags.hasFlag(flags.noAdjustSpawn))
-                .generator(parsedFlags.flagValue(flags.generator, ""))
-                .generatorSettings(parsedFlags.flagValue(flags.generatorSettings, ""))
-                .generateStructures(!parsedFlags.hasFlag(flags.noStructures)))
+                        .biome(parsedFlags.flagValue(flags.biome, ""))
+                        .bonusChest(parsedFlags.hasFlag(flags.bonusChest))
+                        .environment(environment)
+                        .forcedSpawnPosition(parsedFlags.flagValue(flags.forceSpawnPosition))
+                        .generator(parsedFlags.flagValue(flags.generator, ""))
+                        .generatorSettings(parsedFlags.flagValue(flags.generatorSettings, ""))
+                        .generateStructures(!parsedFlags.hasFlag(flags.noStructures))
+                        .seed(parsedFlags.flagValue(flags.seed))
+                        .useSpawnAdjust(!parsedFlags.hasFlag(flags.noAdjustSpawn))
+                        .worldPropertyStrings(StringFormatter.parseCSVMap(parsedFlags.flagValue(flags.properties)))
+                        .worldType(parsedFlags.flagValue(flags.worldType, WorldType.NORMAL)))
                 .onSuccess(newWorld -> messageSuccess(issuer, newWorld))
                 .onFailure(failure -> messageFailure(issuer, failure));
     }
@@ -180,6 +188,19 @@ class CreateCommand extends CoreCommand {
                 .addAlias("-b")
                 .completion(input -> biomeProviderFactory.suggestBiomeString(input))
                 .build());
+
+        private final CommandValueFlag<String> properties = flag(CommandValueFlag.builder("--properties", String.class)
+                .addAlias("-p")
+                .build());
+
+        private final CommandFlag bonusChest = flag(CommandFlag.builder("--generate-bonus-chest")
+                .addAlias("-c")
+                .build());
+
+        private final CommandValueFlag<EntityPosition> forceSpawnPosition = flag(CommandValueFlag.builder("--force-spawn-position", EntityPosition.class)
+                .addAlias("-f")
+                .context(input -> Try.of(() -> EntityPosition.fromString(input)).getOrElseThrow(MVInvalidCommandArgument::causeBy))
+                .build());
     }
 
     @Service

src/main/java/org/mvplugins/multiverse/core/commands/DeleteCommand.java

@@ -15,11 +15,11 @@ import org.jvnet.hk2.annotations.Service;
 
 import org.mvplugins.multiverse.core.command.LegacyAliasCommand;
 import org.mvplugins.multiverse.core.command.MVCommandIssuer;
-import org.mvplugins.multiverse.core.command.MVCommandManager;
 import org.mvplugins.multiverse.core.command.flag.ParsedCommandFlags;
-import org.mvplugins.multiverse.core.command.flags.RemovePlayerFlags;
+import org.mvplugins.multiverse.core.command.flags.RemovePlayerDestinationFlags;
 import org.mvplugins.multiverse.core.command.queue.CommandQueueManager;
 import org.mvplugins.multiverse.core.command.queue.CommandQueuePayload;
+import org.mvplugins.multiverse.core.destination.DestinationInstance;
 import org.mvplugins.multiverse.core.locale.MVCorei18n;
 import org.mvplugins.multiverse.core.locale.message.Message;
 import org.mvplugins.multiverse.core.locale.message.MessageReplacement.Replace;
@@ -31,6 +31,8 @@ import org.mvplugins.multiverse.core.world.WorldManager;
 import org.mvplugins.multiverse.core.world.helpers.PlayerWorldTeleporter;
 import org.mvplugins.multiverse.core.world.options.DeleteWorldOptions;
 
+import java.util.Objects;
+
 @Service
 class DeleteCommand extends CoreCommand {
 
@@ -38,7 +40,7 @@ class DeleteCommand extends CoreCommand {
     private final WorldManager worldManager;
     private final PlayerWorldTeleporter playerWorldTeleporter;
     private final WorldTickDeferrer worldTickDeferrer;
-    private final RemovePlayerFlags flags;
+    private final RemovePlayerDestinationFlags flags;
 
     @Inject
     DeleteCommand(
@@ -46,7 +48,7 @@ class DeleteCommand extends CoreCommand {
             @NotNull WorldManager worldManager,
             @NotNull PlayerWorldTeleporter playerWorldTeleporter,
             @NotNull WorldTickDeferrer worldTickDeferrer,
-            @NotNull RemovePlayerFlags flags
+            @NotNull RemovePlayerDestinationFlags flags
     ) {
         this.commandQueueManager = commandQueueManager;
         this.worldManager = worldManager;
@@ -57,8 +59,8 @@ class DeleteCommand extends CoreCommand {
 
     @Subcommand("delete")
     @CommandPermission("multiverse.core.delete")
-    @CommandCompletion("@mvworlds:scope=both @flags:groupName=" + RemovePlayerFlags.NAME)
-    @Syntax("<world>")
+    @CommandCompletion("@mvworlds:scope=both @flags:groupName=" + RemovePlayerDestinationFlags.NAME)
+    @Syntax("<world> [--remove-players [destination]]")
     @Description("{@@mv-core.delete.description}")
     void onDeleteCommand(
             MVCommandIssuer issuer,
@@ -69,7 +71,7 @@ class DeleteCommand extends CoreCommand {
             MultiverseWorld world,
 
             @Optional
-            @Syntax("[--remove-players]")
+            @Syntax("[--remove-players [destination]]")
             @Description("")
             String[] flagArray) {
         ParsedCommandFlags parsedFlags = flags.parse(flagArray);
@@ -84,10 +86,11 @@ class DeleteCommand extends CoreCommand {
     private void runDeleteCommand(MVCommandIssuer issuer, MultiverseWorld world, ParsedCommandFlags parsedFlags) {
         issuer.sendInfo(MVCorei18n.DELETE_DELETING, Replace.WORLD.with(world.getName()));
 
-        var future = parsedFlags.hasFlag(flags.removePlayers)
+        DestinationInstance<?, ?> removeToDestination = parsedFlags.flagValue(flags.removePlayers);
+        var future = Objects.nonNull(removeToDestination)
                         && world.isLoaded()
                         && world instanceof LoadedMultiverseWorld loadedWorld
-                ? playerWorldTeleporter.removeFromWorld(loadedWorld)
+                ? playerWorldTeleporter.transferAllFromWorldToDestination(loadedWorld, removeToDestination)
                 : AsyncAttemptsAggregate.emptySuccess();
 
         future.onSuccess(() -> worldTickDeferrer.deferWorldTick(() -> doWorldDeleting(issuer, world)))
@@ -113,7 +116,7 @@ class DeleteCommand extends CoreCommand {
                 @NotNull WorldManager worldManager,
                 @NotNull PlayerWorldTeleporter playerWorldTeleporter,
                 @NotNull WorldTickDeferrer worldTickDeferrer,
-                @NotNull RemovePlayerFlags flags) {
+                @NotNull RemovePlayerDestinationFlags flags) {
             super(commandQueueManager, worldManager, playerWorldTeleporter, worldTickDeferrer, flags);
         }
 

src/main/java/org/mvplugins/multiverse/core/commands/DumpsCommand.java

@@ -12,13 +12,10 @@ import org.jvnet.hk2.annotations.Service;
 
 import org.mvplugins.multiverse.core.command.flag.CommandFlagsManager;
 import org.mvplugins.multiverse.core.command.flag.FlagBuilder;
-import org.mvplugins.multiverse.core.commands.DumpsLogPoster.LogsType;
+import org.mvplugins.multiverse.core.command.flag.ParsedCommandFlags;
 import org.mvplugins.multiverse.core.commands.DumpsLogPoster.UploadType;
 import org.mvplugins.multiverse.core.command.MVCommandIssuer;
-import org.mvplugins.multiverse.core.command.MVCommandManager;
-import org.mvplugins.multiverse.core.command.flag.CommandFlag;
 import org.mvplugins.multiverse.core.command.flag.CommandValueFlag;
-import org.mvplugins.multiverse.core.command.flag.ParsedCommandFlags;
 
 @Service
 final class DumpsCommand extends CoreCommand {
@@ -35,22 +32,17 @@ final class DumpsCommand extends CoreCommand {
     @Subcommand("dumps")
     @CommandPermission("multiverse.core.dumps")
     @CommandCompletion("@flags:groupName=" + Flags.NAME)
-    @Syntax("[--logs <mclogs | append>] [--upload <pastesdev | pastegg>] [--paranoid]")
+    @Syntax("[--upload <pastesdev|mclogs>]")
     @Description("{@@mv-core.dumps.description}")
     void onDumpsCommand(
             MVCommandIssuer issuer,
 
             @Optional
-            @Syntax("[--logs <mclogs | append>] [--upload <pastesdev | pastegg>] [--paranoid]")
+            @Syntax("[--upload <pastesdev|mclogs>]")
             String[] flagArray) {
         ParsedCommandFlags parsedFlags = flags.parse(flagArray);
-
-        // Grab all our flags
-        boolean paranoid = parsedFlags.hasFlag(flags.paranoid);
-        LogsType logsType = parsedFlags.flagValue(flags.logs, LogsType.MCLOGS);
         UploadType servicesType = parsedFlags.flagValue(flags.upload, UploadType.PASTESDEV);
-
-        dumpsService.postLogs(issuer, logsType, servicesType, paranoid);
+        dumpsService.postLogs(issuer, servicesType);
     }
 
     @Service
@@ -63,19 +55,9 @@ final class DumpsCommand extends CoreCommand {
             super(NAME, flagsManager);
         }
 
-        private final CommandValueFlag<LogsType> logs = flag(CommandValueFlag
-                .enumBuilder("--logs", LogsType.class)
-                .addAlias("-l")
-                .build());
-
         private final CommandValueFlag<UploadType> upload = flag(CommandValueFlag
                 .enumBuilder("--upload", UploadType.class)
                 .addAlias("-u")
                 .build());
-
-        // Does not upload logs or plugin list (except if --logs mclogs is there)
-        private final CommandFlag paranoid = flag(CommandFlag.builder("--paranoid")
-                .addAlias("-p")
-                .build());
     }
 }

src/main/java/org/mvplugins/multiverse/core/commands/DumpsLogPoster.java

@@ -1,11 +1,19 @@
 package org.mvplugins.multiverse.core.commands;
 
+import java.lang.management.ManagementFactory;
+import java.time.Instant;
+import java.util.Date;
 import java.util.Map;
 
 import com.dumptruckman.minecraft.util.Logging;
+import io.vavr.control.Option;
+import net.minidev.json.JSONArray;
+import net.minidev.json.JSONObject;
+import org.bukkit.plugin.Plugin;
 import org.bukkit.scheduler.BukkitRunnable;
 import org.jetbrains.annotations.NotNull;
 
+import org.mvplugins.multiverse.core.MultiverseCore;
 import org.mvplugins.multiverse.core.command.MVCommandIssuer;
 import org.mvplugins.multiverse.core.event.MVDumpsDebugInfoEvent;
 import org.mvplugins.multiverse.core.locale.MVCorei18n;
@@ -18,8 +26,10 @@ final class DumpsLogPoster extends BukkitRunnable {
 
     enum UploadType {
         // BEGIN CHECKSTYLE-SUPPRESSION: JavadocVariable
-        PASTEGG(PasteServiceType.PASTEGG, "paste.gg"),
-        PASTESDEV(PasteServiceType.PASTESDEV, "pastes.dev");
+        // PASTEBIN(PasteServiceType.PASTEBIN, "pastebin.com"),
+        PASTESDEV(PasteServiceType.PASTESDEV, "pastes.dev"),
+        MCLOGS(PasteServiceType.MCLOGS, "mclo.gs"),
+        ;
         // END CHECKSTYLE-SUPPRESSION: JavadocVariable
 
         private final PasteServiceType pasteServiceType;
@@ -31,34 +41,21 @@ final class DumpsLogPoster extends BukkitRunnable {
         }
     }
 
-    enum LogsType {
-        /**
-         * Appends the log file to the debug info.
-         */
-        APPEND,
-        /**
-         * Uploads the log file to a paste service.
-         */
-        MCLOGS
-    }
-
+    @NotNull
+    private final MultiverseCore plugin;
     private final MVCommandIssuer issuer;
-    private final LogsType logsType;
     private final UploadType uploadType;
-    private final boolean paranoid;
     private final String logs;
     private final MVDumpsDebugInfoEvent versionEvent;
 
-    DumpsLogPoster(@NotNull MVCommandIssuer issuer,
-                   @NotNull DumpsLogPoster.LogsType logsType,
+    DumpsLogPoster(@NotNull MultiverseCore core,
+                   @NotNull MVCommandIssuer issuer,
                    @NotNull DumpsLogPoster.UploadType uploadType,
-                   boolean paranoid,
                    @NotNull String logs,
                    @NotNull MVDumpsDebugInfoEvent versionEvent) {
+        this.plugin = core;
         this.issuer = issuer;
-        this.logsType = logsType;
         this.uploadType = uploadType;
-        this.paranoid = paranoid;
         this.logs = logs;
         this.versionEvent = versionEvent;
     }
@@ -69,24 +66,12 @@ final class DumpsLogPoster extends BukkitRunnable {
         handleVersionEvent();
     }
 
-    @SuppressWarnings("checkstyle:MissingSwitchDefault")
     private void handleLogs() {
-        Logging.finer("Logs type is: " + logsType);
-
-        if (!paranoid) {
-            switch (logsType) {
-                case MCLOGS -> sendDumpsUrl("Logs", postRawDataToMcLogs(logs));
-                case APPEND -> versionEvent.putDetailedDebugInfo("latest.log", logs);
-                default -> Logging.finer("Not uploading logs.");
-            }
-        } else {
-            Logging.finer("Paranoid mode is on, not uploading logs.");
-        }
+        versionEvent.putDetailedDebugInfo("latest.log", logs);
     }
 
     private void handleVersionEvent() {
         Logging.finer("Upload service is: " + uploadType);
-
         final Map<String, String> files = versionEvent.getDetailedDebugInfo();
         sendDumpsUrl(uploadType.serviceName, postFilesToService(files));
     }
@@ -95,37 +80,77 @@ final class DumpsLogPoster extends BukkitRunnable {
         issuer.sendInfo(MVCorei18n.DUMPS_URL_LIST, "{service}", service, "{link}", url);
     }
 
-    private String postRawDataToMcLogs(@NotNull String rawPasteData) {
-        PasteService pasteService = PasteServiceFactory.getService(PasteServiceType.MCLOGS, true);
-
-        return pasteToService(() -> pasteService.postData(rawPasteData));
-    }
-
     private String postFilesToService(@NotNull Map<String, String> pasteFiles) {
-        PasteService pasteService = PasteServiceFactory.getService(uploadType.pasteServiceType, true);
-
-        return pasteToService(() -> {
-            if (pasteService.supportsMultiFile()) {
-                return pasteService.postData(pasteFiles);
-            } else {
-                return pasteService.postData(this.encodeAsString(pasteFiles));
-            }
-        });
+        PasteService pasteService = PasteServiceFactory.getService(uploadType.pasteServiceType, false);
+        return pasteToService(() -> pasteService.postData(encodePasteAsJson(pasteFiles)));
     }
 
-    private String encodeAsString(Map<String, String> files) {
-        StringBuilder uploadData = new StringBuilder();
-        for (Map.Entry<String, String> entry : files.entrySet()) {
-            String file = entry.getKey();
-            String data = entry.getValue();
-            uploadData.append("# ---------- ")
-                    .append(file)
-                    .append(" ----------\n\n")
-                    .append(data)
-                    .append("\n\n");
+    private String encodePasteAsJson(Map<String, String> files) {
+        JSONObject rootObject = new JSONObject();
+        JSONArray plugins = new JSONArray();
+        JSONArray filesObject = new JSONArray();
+
+        for (Plugin plugin : plugin.getServer().getPluginManager().getPlugins()) {
+            plugins.add(new JSONObject(Map.of(
+                    "name", plugin.getName(),
+                    "version", plugin.getDescription().getVersion(),
+                    "description", Option.of(plugin.getDescription().getDescription()).getOrElse(""),
+                    "authors", plugin.getDescription().getAuthors(),
+                    "website", Option.of(plugin.getDescription().getWebsite()).getOrElse(""),
+                    "enabled", plugin.isEnabled()
+            )));
         }
 
-        return uploadData.toString();
+        for (Map.Entry<String, String> entry : files.entrySet()) {
+            String fileType = "text";
+            if (entry.getKey().endsWith(".yml") || entry.getKey().endsWith(".yaml")) {
+                fileType = "yaml";
+            } else if (entry.getKey().endsWith(".json")) {
+                fileType = "json";
+            } else if (entry.getKey().endsWith(".md")) {
+                fileType = "markdown";
+            } else if (entry.getKey().endsWith(".log")) {
+                fileType = "accesslog";
+            }
+
+            filesObject.add(new JSONObject(Map.of(
+                    "name", entry.getKey(),
+                    "data", entry.getValue(),
+                    "type", fileType
+            )));
+        }
+        rootObject.put("server", new JSONObject(Map.of(
+                "name", plugin.getServer().getName(),
+                "version", plugin.getServer().getVersion(),
+                "bukkitVersion", plugin.getServer().getBukkitVersion(),
+                "onlineMode", plugin.getServer().getOnlineMode(),
+                "javaVersion", Runtime.version().toString(),
+                "operatingSystem", System.getProperty("os.name") + " " + System.getProperty("os.version") + " " + System.getProperty("os.arch"),
+                "uptime", calculateUptimeString(),
+                "memory", "%d free / %d total / %d max".formatted(
+                        toMb(Runtime.getRuntime().freeMemory()),
+                        toMb(Runtime.getRuntime().totalMemory()),
+                        toMb(Runtime.getRuntime().maxMemory()))
+        )));
+
+        rootObject.put("plugins", plugins);
+        rootObject.put("files", filesObject);
+        rootObject.put("createdAt", Instant.now().toString());
+
+        return rootObject.toJSONString();
+    }
+
+    private long toMb(long value) {
+        return value / 1024 / 1024;
+    }
+
+    private String calculateUptimeString() {
+        long uptimeMs = System.currentTimeMillis() - ManagementFactory.getRuntimeMXBean().getStartTime();
+        long totalSeconds = uptimeMs / 1000;
+        long hours = totalSeconds / 3600;
+        long minutes = (totalSeconds % 3600) / 60;
+        long seconds = totalSeconds % 60;
+        return String.format("%d hrs, %d mins, %d sec", hours, minutes, seconds);
     }
 
     private String pasteToService(LogPaster paster) {

src/main/java/org/mvplugins/multiverse/core/commands/DumpsService.java

@@ -5,17 +5,15 @@ import java.io.IOException;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
-import java.util.Arrays;
 
 import com.dumptruckman.minecraft.util.Logging;
 import jakarta.inject.Inject;
-import org.apache.commons.lang3.StringUtils;
 import org.jetbrains.annotations.NotNull;
 import org.jvnet.hk2.annotations.Service;
 
 import org.mvplugins.multiverse.core.MultiverseCore;
+import org.mvplugins.multiverse.core.locale.MVCorei18n;
 import org.mvplugins.multiverse.core.module.MultiverseModulesRegistry;
-import org.mvplugins.multiverse.core.commands.DumpsLogPoster.LogsType;
 import org.mvplugins.multiverse.core.commands.DumpsLogPoster.UploadType;
 import org.mvplugins.multiverse.core.command.MVCommandIssuer;
 import org.mvplugins.multiverse.core.event.MVDumpsDebugInfoEvent;
@@ -39,16 +37,12 @@ final class DumpsService {
         this.fileUtils = fileUtils;
     }
 
-    void postLogs(MVCommandIssuer issuer, LogsType logsType, UploadType servicesType, boolean paranoid) {
+    void postLogs(MVCommandIssuer issuer, UploadType servicesType) {
+        issuer.sendInfo(MVCorei18n.DUMPS_STARTING);
+
         // Initialise and add info to the debug event
         MVDumpsDebugInfoEvent versionEvent = createAndCallDebugInfoEvent();
-
-        // Add plugin list if user isn't paranoid
-        if (!paranoid) {
-            versionEvent.putDetailedDebugInfo("plugins.md", "# Plugins\n\n" + getPluginList());
-        }
-
-        new DumpsLogPoster(issuer, logsType, servicesType, paranoid, getLogs(), versionEvent)
+        new DumpsLogPoster(plugin, issuer, servicesType, getLogs(), versionEvent)
                 .runTaskAsynchronously(plugin);
     }
 
@@ -73,18 +67,18 @@ final class DumpsService {
     private @NotNull String readLogsFromFile(Path logsPath) {
         String logs = "Could not read log";
 
-        // Try reading as ANSI encoded
+        // Try reading as UTF-8 first
         try {
             logs = Files.readString(logsPath, StandardCharsets.UTF_8);
         } catch (IOException e) {
-            Logging.severe("Could not read logs/latest.log. See below for stack trace");
+            Logging.severe("Could not read logs/latest.log as UTF-8. Trying ISO-8859-1. See below for stack trace");
             e.printStackTrace();
 
             try {
-                logs = Files.readString(logsPath, StandardCharsets.UTF_8);
+                logs = Files.readString(logsPath, StandardCharsets.ISO_8859_1);
             } catch (IOException ex) {
                 // It is some other strange encoding
-                Logging.severe("Could not read ./logs/latest.log. See below for stack trace");
+                Logging.severe("Could not read ./logs/latest.log as ISO-8859-1. See below for stack trace");
                 ex.printStackTrace();
             }
         }
@@ -92,15 +86,6 @@ final class DumpsService {
         return logs;
     }
 
-    private String getDebugInfoString() {
-        return "# Multiverse-Core Version info" + "\n\n"
-                + " - Multiverse-Core Version: " + this.plugin.getDescription().getVersion() + '\n'
-                + " - Bukkit Version: " + this.plugin.getServer().getVersion() + '\n'
-                + " - Loaded Worlds: " + worldManager.getLoadedWorlds() + '\n'
-                + " - Multiverse Plugins Loaded: " + StringFormatter.joinAnd(MultiverseModulesRegistry.get().getRegisteredPlugins()) + '\n'
-                + " - Multiverse Plugins Count: " + MultiverseModulesRegistry.get().getPluginCount() + '\n';
-    }
-
     private MVDumpsDebugInfoEvent createAndCallDebugInfoEvent() {
         MVDumpsDebugInfoEvent event = new MVDumpsDebugInfoEvent();
         addDebugInfoToEvent(event);
@@ -112,34 +97,63 @@ final class DumpsService {
         // Add the legacy file, but as markdown, so it's readable
         event.putDetailedDebugInfo("version.md", this.getDebugInfoString());
 
-        // add config.yml
-        File configFile = new File(plugin.getDataFolder(), "config.yml");
-        event.putDetailedDebugInfo("Multiverse-Core/config.yml", configFile);
-
-        // add worlds.yml
-        File worldsFile = new File(plugin.getDataFolder(), "worlds.yml");
-        event.putDetailedDebugInfo("Multiverse-Core/worlds.yml", worldsFile);
-
-        // Add bukkit.yml if we found it
-        if (fileUtils.getBukkitConfig() != null) {
-            event.putDetailedDebugInfo(fileUtils.getBukkitConfig().getPath(), fileUtils.getBukkitConfig());
-        } else {
-            Logging.warning("/mv dumps could not find bukkit.yml. Not including file");
-        }
-
         // Add server.properties if we found it
         if (fileUtils.getServerProperties() != null) {
-            event.putDetailedDebugInfo(fileUtils.getServerProperties().getPath(), fileUtils.getServerProperties());
+            event.putDetailedDebugInfo(fileUtils.getServerProperties().getName(), fileUtils.getServerProperties());
         } else {
             Logging.warning("/mv dumps could not find server.properties. Not including file");
         }
 
+        // Add bukkit.yml if we found it
+        if (fileUtils.getBukkitConfig() != null) {
+            event.putDetailedDebugInfo(fileUtils.getBukkitConfig().getName(), fileUtils.getBukkitConfig());
+        } else {
+            Logging.warning("/mv dumps could not find bukkit.yml. Not including file");
+        }
+
+        // Add spigot.yml
+        File spigotYml = fileUtils.getServerFolder().toPath().resolve("spigot.yml").toFile();
+        if (spigotYml.isFile()) {
+            event.putDetailedDebugInfo(spigotYml.getName(), spigotYml);
+        } else {
+            Logging.warning("/mv dumps could not find spigot.yml. Not including file");
+        }
+
+        // Add paper-global.yml
+        File paperGlobalYml = fileUtils.getServerFolder().toPath().resolve("config/paper-global.yml").toFile();
+        if (paperGlobalYml.isFile()) {
+            event.putDetailedDebugInfo(paperGlobalYml.getName(), paperGlobalYml);
+        } else {
+            Logging.warning("/mv dumps could not find paper-global.yml. Not including file");
+        }
+
+        // add paper-world-defaults.yml
+        File paperWorldDefaultsYml = fileUtils.getServerFolder().toPath().resolve("config/paper-world-defaults.yml").toFile();
+        if (paperWorldDefaultsYml.isFile()) {
+            event.putDetailedDebugInfo(paperWorldDefaultsYml.getName(), paperWorldDefaultsYml);
+        } else {
+            Logging.warning("/mv dumps could not find paper-global.yml. Not including file");
+        }
+
+        // add multiverse-core config.yml
+        File configFile = new File(plugin.getDataFolder(), "config.yml");
+        event.putDetailedDebugInfo("multiverse-core/config.yml", configFile);
+
+        // add multiverse-core worlds.yml
+        File worldsFile = new File(plugin.getDataFolder(), "worlds.yml");
+        event.putDetailedDebugInfo("multiverse-core/worlds.yml", worldsFile);
+
+        // add multiverse-core anchors.yml
+        File anchorsFile = new File(plugin.getDataFolder(), "anchors.yml");
+        event.putDetailedDebugInfo("multiverse-core/anchors.yml", anchorsFile);
     }
 
-    private String getPluginList() {
-        return " - " + StringUtils.join(Arrays.stream(plugin.getServer().getPluginManager().getPlugins())
-                .map(Object::toString)
-                .sorted()
-                .toList(), "\n - ");
+    private String getDebugInfoString() {
+        return "# Multiverse-Core Version info" + "\n\n"
+                + " - Multiverse-Core Version: " + this.plugin.getDescription().getVersion() + '\n'
+                + " - Bukkit Version: " + this.plugin.getServer().getVersion() + '\n'
+                + " - Loaded Worlds: " + worldManager.getLoadedWorlds() + '\n'
+                + " - Multiverse Plugins Loaded: " + StringFormatter.joinAnd(MultiverseModulesRegistry.get().getRegisteredPlugins()) + '\n'
+                + " - Multiverse Plugins Count: " + MultiverseModulesRegistry.get().getPluginCount() + '\n';
     }
 }

src/main/java/org/mvplugins/multiverse/core/commands/ImportCommand.java

@@ -48,7 +48,7 @@ class ImportCommand extends CoreCommand {
     void onImportCommand(
             MVCommandIssuer issuer,
 
-            @Conditions("worldname:scope=new")
+            // @Conditions("worldname:scope=new")
             @Syntax("<name>")
             @Description("{@@mv-core.import.name.description}")
             String worldName,
@@ -67,7 +67,8 @@ class ImportCommand extends CoreCommand {
         worldManager.importWorld(ImportWorldOptions.worldName(worldName)
                         .biome(parsedFlags.flagValue(flags.biome, ""))
                         .environment(environment)
-                        .generator(parsedFlags.flagValue(flags.generator, String.class))
+                        .generator(parsedFlags.flagValue(flags.generator))
+                        .generatorSettings(parsedFlags.flagValue(flags.generatorSettings, ""))
                         .useSpawnAdjust(!parsedFlags.hasFlag(flags.noAdjustSpawn))
                         .doFolderCheck(!parsedFlags.hasFlag(flags.skipFolderCheck)))
                 .onSuccess(newWorld -> {
@@ -110,6 +111,11 @@ class ImportCommand extends CoreCommand {
         private final CommandFlag skipFolderCheck = flag(CommandFlag.builder("--skip-folder-check")
                 .addAlias("-f")
                 .build());
+
+        private final CommandValueFlag<String> generatorSettings = flag(CommandValueFlag
+                .builder("--generator-settings", String.class)
+                .addAlias("-gs")
+                .build());
     }
 
     @Service

src/main/java/org/mvplugins/multiverse/core/commands/InfoCommand.java

@@ -87,6 +87,7 @@ class InfoCommand extends CoreCommand {
     private Map<String, String> getInfo(LoadedMultiverseWorld world) {
         Map<String, String> outMap = new LinkedHashMap<>();
 
+        outMap.put("World Key", world.getKey().toString());
         outMap.put("World Name", world.getName());
         outMap.put("World Alias", world.getAlias());
         outMap.put("World UID", world.getUID().toString());
@@ -103,6 +104,7 @@ class InfoCommand extends CoreCommand {
         outMap.put("World Type", world.getWorldType().map(WorldType::getName).getOrNull());
         outMap.put("Biome", world.getBiome());
         outMap.put("Generator", world.getGenerator());
+        outMap.put("Generator Settings",  world.getGeneratorSettings());
         outMap.put("Generate Structures", world.canGenerateStructures().map(String::valueOf).getOrNull());
 
         outMap.put("Auto Load", String.valueOf(world.isAutoLoad()));
@@ -112,13 +114,12 @@ class InfoCommand extends CoreCommand {
         outMap.put("World Scale", String.valueOf(world.getScale()));
         outMap.put("Weather Enabled", String.valueOf(world.isAllowWeather()));
         outMap.put("Allow Flight", String.valueOf(world.isAllowFlight()));
+        outMap.put("Grant Advancements", String.valueOf(world.isAllowAdvancementGrant()));
+        outMap.put("Auto Heal", String.valueOf(world.getAutoHeal()));
         outMap.put("Hunger Depletes", String.valueOf(world.isHunger()));
-        outMap.put("Keep Spawn In Memory", String.valueOf(world.isKeepSpawnInMemory()));
         outMap.put("PVP Enabled", String.valueOf(world.getPvp()));
         outMap.put("Portal Form", String.valueOf(world.getPortalForm()));
         outMap.put("Player Limit", String.valueOf(world.getPlayerLimit()));
-//        getAnimalSpawningInfo(outMap, world);
-//        getMonsterSpawningInfo(outMap, world);
         outMap.put("World Blacklist", String.join(", ", world.getWorldBlacklist()));
 
         return outMap;
@@ -135,30 +136,6 @@ class InfoCommand extends CoreCommand {
         }
     }
 
-//    private void getAnimalSpawningInfo(Map<String, String> outMap, MultiverseWorld world) {
-//        if (world.isSpawningAnimals()) {
-//            outMap.put("Spawning Animals", "ALL");
-//        } else {
-//            if (!world.getSpawningAnimalsExceptions().isEmpty()) {
-//                outMap.put("Spawning Animals", world.getSpawningAnimalsExceptions().toString());
-//            } else {
-//                outMap.put("Spawning Animals", "NONE");
-//            }
-//        }
-//    }
-//
-//    private void getMonsterSpawningInfo(Map<String, String> outMap, MultiverseWorld world) {
-//        if (world.isSpawningMonsters()) {
-//            outMap.put("Spawning Monsters", "ALL");
-//        } else {
-//            if (!world.getSpawningMonstersExceptions().isEmpty()) {
-//                outMap.put("Spawning Monsters", world.getSpawningMonstersExceptions().toString());
-//            } else {
-//                outMap.put("Spawning Monsters", "NONE");
-//            }
-//        }
-//    }
-
     @Service
     private static final class LegacyAlias extends InfoCommand implements LegacyAliasCommand {
         @Inject

src/main/java/org/mvplugins/multiverse/core/commands/LoadCommand.java

@@ -16,8 +16,8 @@ import org.mvplugins.multiverse.core.command.LegacyAliasCommand;
 import org.mvplugins.multiverse.core.command.MVCommandIssuer;
 import org.mvplugins.multiverse.core.command.flag.CommandFlag;
 import org.mvplugins.multiverse.core.command.flag.CommandFlagsManager;
+import org.mvplugins.multiverse.core.command.flag.FlagBuilder;
 import org.mvplugins.multiverse.core.command.flag.ParsedCommandFlags;
-import org.mvplugins.multiverse.core.command.flags.RemovePlayerFlags;
 import org.mvplugins.multiverse.core.locale.MVCorei18n;
 import org.mvplugins.multiverse.core.locale.message.MessageReplacement.Replace;
 import org.mvplugins.multiverse.core.world.MultiverseWorld;
@@ -38,7 +38,7 @@ class LoadCommand extends CoreCommand {
 
     @Subcommand("load")
     @CommandPermission("multiverse.core.load")
-    @CommandCompletion("@mvworlds:scope=unloaded")
+    @CommandCompletion("@mvworlds:scope=unloaded @flags:groupName=" + Flags.NAME)
     @Syntax("<world>")
     @Description("{@@mv-core.load.description}")
     void onLoadCommand(
@@ -49,7 +49,7 @@ class LoadCommand extends CoreCommand {
             MultiverseWorld world,
 
             @Optional
-            @Syntax("[--remove-players]")
+            @Syntax("[--skip-folder-check]")
             @Description("")
             String[] flagArray) {
         ParsedCommandFlags parsedFlags = flags.parse(flagArray);
@@ -67,9 +67,9 @@ class LoadCommand extends CoreCommand {
     }
 
     @Service
-    private static final class Flags extends RemovePlayerFlags {
+    private static final class Flags extends FlagBuilder {
 
-        private static final String NAME = "mvunload";
+        private static final String NAME = "mvload";
 
         @Inject
         private Flags(@NotNull CommandFlagsManager flagsManager) {

src/main/java/org/mvplugins/multiverse/core/commands/MetaCommand.java

@@ -0,0 +1,121 @@
+package org.mvplugins.multiverse.core.commands;
+
+import co.aikar.commands.annotation.CommandCompletion;
+import co.aikar.commands.annotation.CommandPermission;
+import co.aikar.commands.annotation.Description;
+import co.aikar.commands.annotation.Flags;
+import co.aikar.commands.annotation.Optional;
+import co.aikar.commands.annotation.Single;
+import co.aikar.commands.annotation.Subcommand;
+import co.aikar.commands.annotation.Syntax;
+import jakarta.inject.Inject;
+import org.bukkit.ChatColor;
+import org.jetbrains.annotations.NotNull;
+import org.jvnet.hk2.annotations.Service;
+import org.mvplugins.multiverse.core.command.MVCommandIssuer;
+import org.mvplugins.multiverse.core.command.flag.ParsedCommandFlags;
+import org.mvplugins.multiverse.core.command.flags.PageFilterFlags;
+import org.mvplugins.multiverse.core.display.ContentDisplay;
+import org.mvplugins.multiverse.core.display.filters.DefaultContentFilter;
+import org.mvplugins.multiverse.core.display.handlers.PagedSendHandler;
+import org.mvplugins.multiverse.core.display.parsers.MapContentProvider;
+import org.mvplugins.multiverse.core.locale.MVCorei18n;
+import org.mvplugins.multiverse.core.locale.message.Message;
+import org.mvplugins.multiverse.core.locale.message.MessageReplacement.Replace;
+import org.mvplugins.multiverse.core.world.MultiverseWorld;
+import org.mvplugins.multiverse.core.world.WorldManager;
+
+import java.util.Locale;
+
+import static org.mvplugins.multiverse.core.locale.message.MessageReplacement.replace;
+
+@Service
+@Subcommand("meta")
+final class MetaCommand extends CoreCommand {
+
+    private final WorldManager worldManager;
+    private final PageFilterFlags flags;
+
+    @Inject
+    MetaCommand(@NotNull WorldManager worldManager, @NotNull PageFilterFlags flags) {
+        this.worldManager = worldManager;
+        this.flags = flags;
+    }
+
+    @Subcommand("info")
+    @CommandPermission("multiverse.core.meta.info")
+    @CommandCompletion("@mvworlds:scope=both|@flags:resolveUntil=arg1,groupName=" + PageFilterFlags.NAME + " " +
+            "@flags:groupName=" + PageFilterFlags.NAME)
+    @Syntax("[world] [--page <page>] [--filter <filter>]")
+    @Description("{@@mv-core.meta.info.description}")
+    void infoCommand(
+            MVCommandIssuer issuer,
+
+            @Flags("resolve=issuerAware,maxArgForAware=0")
+            @Syntax("[world]")
+            @Description("{@@mv-core.meta.info.world.description}")
+            MultiverseWorld world,
+
+            @Optional
+            @Syntax("[--page <page>] [--filter <filter>]")
+            String[] flagArray
+    ) {
+        ParsedCommandFlags parsedFlags = flags.parse(flagArray);
+        ContentDisplay.create()
+                .addContent(MapContentProvider.forContent(world.getAllMeta())
+                        .withKeyColor(ChatColor.AQUA)
+                        .withValueColor(ChatColor.WHITE))
+                .withSendHandler(PagedSendHandler.create()
+                        .withHeader(Message.of(MVCorei18n.META_INFO_HEADER, replace("{world}").with(world.getName())))
+                        .noContentMessage(Message.of(MVCorei18n.META_INFO_NOCONTENT, replace("{world}").with(world.getName())))
+                        .withTargetPage(parsedFlags.flagValue(flags.page, 1))
+                        .withFilter(parsedFlags.flagValue(flags.filter, DefaultContentFilter.get())))
+                .send(issuer);
+    }
+
+    @Subcommand("modify")
+    @CommandPermission("multiverse.core.meta.modify")
+    @CommandCompletion("@mvworlds:scope=both set|remove @mvworldmetakey @empty")
+    @Syntax("[world] <set|remove> <key> [value]")
+    void modifyCommand(
+            MVCommandIssuer issuer,
+
+            @Flags("resolve=issuerAware,maxArgForAware=4")
+            @Syntax("[world]")
+            MultiverseWorld world,
+
+            @Syntax("<set|remove>")
+            String action,
+
+            @Syntax("<key>")
+            String key,
+
+            @Optional
+            @Single
+            @Syntax("[value]")
+            String value
+    ) {
+        switch (action.toLowerCase(Locale.ROOT)) {
+            case "set" -> world.setMeta(key, value)
+                    .onSuccess(ignore -> issuer.sendInfo(MVCorei18n.META_MODIFY_SET_SUCCESS,
+                                    replace("{key}").with(key),
+                                    replace("{value}").with(value),
+                                    Replace.WORLD.with(world.getName())))
+                    .onFailure(throwable -> issuer.sendError(MVCorei18n.META_MODIFY_SET_FAILURE,
+                            replace("{key}").with(key),
+                            replace("{value}").with(value),
+                            Replace.WORLD.with(world.getName()),
+                            Replace.ERROR.with(throwable)));
+            case "remove" -> world.removeMeta(key)
+                    .onSuccess(ignore -> issuer.sendInfo(MVCorei18n.META_MODIFY_REMOVE_SUCCESS,
+                            replace("{key}").with(key),
+                            Replace.WORLD.with(world.getName())))
+                    .onFailure(throwable -> issuer.sendError(MVCorei18n.META_MODIFY_REMOVE_FAILURE,
+                            replace("{key}").with(key),
+                            Replace.WORLD.with(world.getName()),
+                            Replace.ERROR.with(throwable)));
+            default -> issuer.sendError(MVCorei18n.META_MODIFY_INVALIDACTION, replace("{action}").with(action));
+        }
+        worldManager.saveWorldsConfig();
+    }
+}

src/main/java/org/mvplugins/multiverse/core/commands/RegenCommand.java

@@ -2,6 +2,7 @@ package org.mvplugins.multiverse.core.commands;
 
 import java.util.Collections;
 import java.util.List;
+import java.util.Objects;
 
 import co.aikar.commands.ACFUtil;
 import co.aikar.commands.annotation.CommandAlias;
@@ -23,9 +24,12 @@ import org.mvplugins.multiverse.core.command.flag.CommandFlag;
 import org.mvplugins.multiverse.core.command.flag.CommandFlagsManager;
 import org.mvplugins.multiverse.core.command.flag.CommandValueFlag;
 import org.mvplugins.multiverse.core.command.flag.ParsedCommandFlags;
-import org.mvplugins.multiverse.core.command.flags.RemovePlayerFlags;
+import org.mvplugins.multiverse.core.command.flags.RemovePlayerDestinationFlags;
 import org.mvplugins.multiverse.core.command.queue.CommandQueueManager;
 import org.mvplugins.multiverse.core.command.queue.CommandQueuePayload;
+import org.mvplugins.multiverse.core.destination.DestinationInstance;
+import org.mvplugins.multiverse.core.destination.DestinationsProvider;
+import org.mvplugins.multiverse.core.destination.core.WorldDestination;
 import org.mvplugins.multiverse.core.locale.MVCorei18n;
 import org.mvplugins.multiverse.core.locale.message.Message;
 import org.mvplugins.multiverse.core.locale.message.MessageReplacement.Replace;
@@ -65,7 +69,8 @@ class RegenCommand extends CoreCommand {
     @Subcommand("regen")
     @CommandPermission("multiverse.core.regen")
     @CommandCompletion("@mvworlds:scope=loaded @flags:groupName=" + Flags.NAME)
-    @Syntax("<world> [--seed [seed] --reset-world-config --reset-gamerules --reset-world-border --remove-players]")
+    @Syntax("<world> [--seed [seed]] [--reset-world-config] [--reset-gamerules] [--reset-world-border] " +
+            "[--remove-players [destination]]")
     @Description("{@@mv-core.regen.description}")
     void onRegenCommand(
             MVCommandIssuer issuer,
@@ -75,7 +80,8 @@ class RegenCommand extends CoreCommand {
             LoadedMultiverseWorld world,
 
             @Optional
-            @Syntax("[--seed [seed] --reset-world-config --reset-gamerules --reset-world-border --remove-players]")
+            @Syntax("[--seed [seed]] [--reset-world-config] [--reset-gamerules] [--reset-world-border] " +
+                    "[--remove-players [destination]]")
             @Description("{@@mv-core.regen.other.description}")
             String[] flagArray) {
         ParsedCommandFlags parsedFlags = flags.parse(flagArray);
@@ -91,8 +97,9 @@ class RegenCommand extends CoreCommand {
         issuer.sendInfo(MVCorei18n.REGEN_REGENERATING, Replace.WORLD.with(world.getName()));
         List<Player> worldPlayers = world.getPlayers().getOrElse(Collections.emptyList());
 
-        var future = parsedFlags.hasFlag(flags.removePlayers)
-                ? playerWorldTeleporter.removeFromWorld(world)
+        DestinationInstance<?, ?> removeToDestination = parsedFlags.flagValue(flags.removePlayers);
+        var future = Objects.nonNull(removeToDestination)
+                ? playerWorldTeleporter.transferAllFromWorldToDestination(world,  removeToDestination)
                 : AsyncAttemptsAggregate.emptySuccess();
 
         // todo: using future will hide stacktrace
@@ -128,13 +135,18 @@ class RegenCommand extends CoreCommand {
     }
 
     @Service
-    private static final class Flags extends RemovePlayerFlags {
+    private static final class Flags extends RemovePlayerDestinationFlags {
 
         private static final String NAME = "mvregen";
 
         @Inject
-        private Flags(@NotNull CommandFlagsManager flagsManager) {
-            super(NAME, flagsManager);
+        private Flags(
+                @NotNull CommandFlagsManager flagsManager,
+                @NotNull WorldManager worldManager,
+                @NotNull DestinationsProvider destinationsProvider,
+                @NotNull WorldDestination worldDestination
+        ) {
+            super(NAME, flagsManager, worldManager, destinationsProvider, worldDestination);
         }
 
         private final CommandValueFlag<String> seed = flag(CommandValueFlag.builder("--seed", String.class)

src/main/java/org/mvplugins/multiverse/core/commands/RemoveCommand.java

@@ -14,11 +14,13 @@ import org.jvnet.hk2.annotations.Service;
 
 import org.mvplugins.multiverse.core.command.LegacyAliasCommand;
 import org.mvplugins.multiverse.core.command.MVCommandIssuer;
-import org.mvplugins.multiverse.core.command.MVCommandManager;
 import org.mvplugins.multiverse.core.command.flag.CommandFlag;
 import org.mvplugins.multiverse.core.command.flag.CommandFlagsManager;
 import org.mvplugins.multiverse.core.command.flag.ParsedCommandFlags;
-import org.mvplugins.multiverse.core.command.flags.RemovePlayerFlags;
+import org.mvplugins.multiverse.core.command.flags.RemovePlayerDestinationFlags;
+import org.mvplugins.multiverse.core.destination.DestinationInstance;
+import org.mvplugins.multiverse.core.destination.DestinationsProvider;
+import org.mvplugins.multiverse.core.destination.core.WorldDestination;
 import org.mvplugins.multiverse.core.locale.MVCorei18n;
 import org.mvplugins.multiverse.core.locale.message.MessageReplacement.Replace;
 import org.mvplugins.multiverse.core.utils.result.AsyncAttemptsAggregate;
@@ -27,6 +29,8 @@ import org.mvplugins.multiverse.core.world.WorldManager;
 import org.mvplugins.multiverse.core.world.helpers.PlayerWorldTeleporter;
 import org.mvplugins.multiverse.core.world.options.RemoveWorldOptions;
 
+import java.util.Objects;
+
 @Service
 class RemoveCommand extends CoreCommand {
 
@@ -48,7 +52,7 @@ class RemoveCommand extends CoreCommand {
     @Subcommand("remove")
     @CommandPermission("multiverse.core.remove")
     @CommandCompletion("@mvworlds:scope=both @flags:groupName=" + Flags.NAME)
-    @Syntax("<world>")
+    @Syntax("<world> [--remove-players [destination]] [--no-unload-bukkit-world] [--no-save]")
     @Description("{@@mv-core.remove.description}")
     void onRemoveCommand(
             MVCommandIssuer issuer,
@@ -58,13 +62,16 @@ class RemoveCommand extends CoreCommand {
             MultiverseWorld world,
 
             @Optional
-            @Syntax("[--remove-players]")
+            @Syntax("[--remove-players [destination]] [--no-unload-bukkit-world] [--no-save]")
             @Description("")
             String[] flagArray) {
         ParsedCommandFlags parsedFlags = flags.parse(flagArray);
 
-        var future = parsedFlags.hasFlag(flags.removePlayers)
-                ? worldManager.getLoadedWorld(world).map(playerWorldTeleporter::removeFromWorld).getOrElse(AsyncAttemptsAggregate::emptySuccess)
+        DestinationInstance<?, ?> removeToDestination = parsedFlags.flagValue(flags.removePlayers);
+        var future = Objects.nonNull(removeToDestination)
+                ? world.asLoadedWorld()
+                  .map(loadedWorld -> playerWorldTeleporter.transferAllFromWorldToDestination(loadedWorld, removeToDestination))
+                  .getOrElse(AsyncAttemptsAggregate::emptySuccess)
                 : AsyncAttemptsAggregate.emptySuccess();
 
         future.onSuccess(() -> doWorldRemoving(issuer, world, parsedFlags))
@@ -85,13 +92,18 @@ class RemoveCommand extends CoreCommand {
     }
 
     @Service
-    private static final class Flags extends RemovePlayerFlags {
+    private static final class Flags extends RemovePlayerDestinationFlags {
 
         private static final String NAME = "mvremove";
 
         @Inject
-        private Flags(@NotNull CommandFlagsManager flagsManager) {
-            super(NAME, flagsManager);
+        private Flags(
+                @NotNull CommandFlagsManager flagsManager,
+                @NotNull WorldManager worldManager,
+                @NotNull DestinationsProvider destinationsProvider,
+                @NotNull WorldDestination worldDestination
+        ) {
+            super(NAME, flagsManager, worldManager, destinationsProvider, worldDestination);
         }
 
         private final CommandFlag noUnloadBukkitWorld = flag(CommandFlag.builder("--no-unload-bukkit-world")

src/main/java/org/mvplugins/multiverse/core/commands/UnloadCommand.java

@@ -14,11 +14,13 @@ import org.jvnet.hk2.annotations.Service;
 
 import org.mvplugins.multiverse.core.command.LegacyAliasCommand;
 import org.mvplugins.multiverse.core.command.MVCommandIssuer;
-import org.mvplugins.multiverse.core.command.MVCommandManager;
 import org.mvplugins.multiverse.core.command.flag.CommandFlag;
 import org.mvplugins.multiverse.core.command.flag.CommandFlagsManager;
 import org.mvplugins.multiverse.core.command.flag.ParsedCommandFlags;
-import org.mvplugins.multiverse.core.command.flags.RemovePlayerFlags;
+import org.mvplugins.multiverse.core.command.flags.RemovePlayerDestinationFlags;
+import org.mvplugins.multiverse.core.destination.DestinationInstance;
+import org.mvplugins.multiverse.core.destination.DestinationsProvider;
+import org.mvplugins.multiverse.core.destination.core.WorldDestination;
 import org.mvplugins.multiverse.core.locale.MVCorei18n;
 import org.mvplugins.multiverse.core.locale.message.MessageReplacement.Replace;
 import org.mvplugins.multiverse.core.utils.result.AsyncAttemptsAggregate;
@@ -27,6 +29,8 @@ import org.mvplugins.multiverse.core.world.WorldManager;
 import org.mvplugins.multiverse.core.world.helpers.PlayerWorldTeleporter;
 import org.mvplugins.multiverse.core.world.options.UnloadWorldOptions;
 
+import java.util.Objects;
+
 @Service
 class UnloadCommand extends CoreCommand {
 
@@ -48,7 +52,7 @@ class UnloadCommand extends CoreCommand {
     @Subcommand("unload")
     @CommandPermission("multiverse.core.unload")
     @CommandCompletion("@mvworlds @flags:groupName=" + Flags.NAME)
-    @Syntax("<world>")
+    @Syntax("<world> [--remove-players [destination]] [--no-save]")
     @Description("{@@mv-core.unload.description}")
     void onUnloadCommand(
             MVCommandIssuer issuer,
@@ -58,15 +62,16 @@ class UnloadCommand extends CoreCommand {
             LoadedMultiverseWorld world,
 
             @Optional
-            @Syntax("[--remove-players] [--no-save]")
+            @Syntax("[--remove-players [destination]] [--no-save]")
             @Description("{@@mv-core.gamerules.description.page}")
             String[] flagArray) {
         ParsedCommandFlags parsedFlags = flags.parse(flagArray);
 
         issuer.sendInfo(MVCorei18n.UNLOAD_UNLOADING, Replace.WORLD.with(world.getAliasOrName()));
 
-        var future = parsedFlags.hasFlag(flags.removePlayers)
-                ? playerWorldTeleporter.removeFromWorld(world)
+        DestinationInstance<?, ?> removeToDestination = parsedFlags.flagValue(flags.removePlayers);
+        var future = Objects.nonNull(removeToDestination)
+                ? playerWorldTeleporter.transferAllFromWorldToDestination(world, removeToDestination)
                 : AsyncAttemptsAggregate.emptySuccess();
 
         future.onSuccess(() -> doWorldUnloading(issuer, world, parsedFlags))
@@ -88,13 +93,18 @@ class UnloadCommand extends CoreCommand {
     }
 
     @Service
-    private static final class Flags extends RemovePlayerFlags {
+    private static final class Flags extends RemovePlayerDestinationFlags {
 
         private static final String NAME = "mvunload";
 
         @Inject
-        private Flags(@NotNull CommandFlagsManager flagsManager) {
-            super(NAME, flagsManager);
+        private Flags(
+                @NotNull CommandFlagsManager flagsManager,
+                @NotNull WorldManager worldManager,
+                @NotNull DestinationsProvider destinationsProvider,
+                @NotNull WorldDestination worldDestination
+        ) {
+            super(NAME, flagsManager, worldManager, destinationsProvider, worldDestination);
         }
 
         private final CommandFlag noUnloadBukkitWorld = flag(CommandFlag.builder("--no-unload-bukkit-world")

src/main/java/org/mvplugins/multiverse/core/commands/WorldBorderCommand.java

@@ -12,8 +12,11 @@ import org.jvnet.hk2.annotations.Service;
 import org.mvplugins.multiverse.core.command.MVCommandIssuer;
 import org.mvplugins.multiverse.core.locale.MVCorei18n;
 import org.mvplugins.multiverse.core.locale.message.MessageReplacement.Replace;
+import org.mvplugins.multiverse.core.utils.compatibility.WorldBorderCompatibility;
+import org.mvplugins.multiverse.core.utils.tick.TickDuration;
 import org.mvplugins.multiverse.core.world.LoadedMultiverseWorld;
 
+import java.time.temporal.ChronoUnit;
 import java.util.function.Consumer;
 
 import static org.mvplugins.multiverse.core.locale.message.MessageReplacement.replace;
@@ -33,15 +36,14 @@ final class WorldBorderCommand extends CoreCommand {
             @Optional
             @Default("0")
             @Syntax("[time]")
-            int time,
+            TickDuration duration,
 
             @Flags("resolve=issuerAware,maxArgForAware=0")
             @Syntax("[world]")
             LoadedMultiverseWorld world
     ) {
-        worldBorderAction(issuer, world, worldBorder -> {
-            onWorldBorderSet(issuer, worldBorder.getSize() + size, time, world);
-        });
+        worldBorderAction(issuer, world, worldBorder ->
+                onWorldBorderSet(issuer, worldBorder.getSize() + size, duration, world));
     }
 
     @Subcommand("center")
@@ -145,7 +147,7 @@ final class WorldBorderCommand extends CoreCommand {
             @Optional
             @Default("0")
             @Syntax("[time]")
-            int time,
+            TickDuration duration,
 
             @Flags("resolve=issuerAware,maxArgForAware=0")
             @Syntax("[world]")
@@ -158,15 +160,18 @@ final class WorldBorderCommand extends CoreCommand {
                         Replace.WORLD.with(world.getAliasOrName()));
                 return;
             }
-            worldBorder.setSize(size, time);
-            if (time <= 0) {
+            if (!WorldBorderCompatibility.supportsChangeSizeInTicks() && !duration.isExactTo(ChronoUnit.SECONDS)) {
+                setRoundOffError(issuer, duration);
+            }
+            WorldBorderCompatibility.changeSizeDuration(worldBorder, size, duration);
+            if (duration.toTicks() <= 0) {
                 issuer.sendMessage(MVCorei18n.WORLDBORDER_SET_IMMEDIATE,
                         replace("{size}").with(worldBorder.getSize()),
                         Replace.WORLD.with(world.getAliasOrName()));
             } else {
                 issuer.sendMessage(previousSize > size ? MVCorei18n.WORLDBORDER_SET_GROWING : MVCorei18n.WORLDBORDER_SET_SHRINKING,
                         replace("{size}").with(size),
-                        replace("{time}").with(time),
+                        replace("{time}").with(String.format("%.2f", duration.toSeconds())),
                         Replace.WORLD.with(world.getAliasOrName()));
             }
         });
@@ -201,25 +206,34 @@ final class WorldBorderCommand extends CoreCommand {
             MVCommandIssuer issuer,
 
             @Syntax("<time>")
-            int time,
+            TickDuration duration,
 
             @Flags("resolve=issuerAware,maxArgForAware=0")
             @Syntax("[world]")
             LoadedMultiverseWorld world
     ) {
         worldBorderAction(issuer, world, worldBorder -> {
-            if (worldBorder.getWarningTime() == time) {
+            if (WorldBorderCompatibility.getWarningTimeTicks(worldBorder) == duration.toTicks()) {
                 issuer.sendMessage(MVCorei18n.WORLDBORDER_WARNINGTIME_NOTHINGCHANGED,
                         Replace.WORLD.with(world.getAliasOrName()));
                 return;
             }
-            worldBorder.setWarningTime(time);
+            if (!WorldBorderCompatibility.supportsSetWarningTimeInTicks() && !duration.isExactTo(ChronoUnit.SECONDS)) {
+                setRoundOffError(issuer, duration);
+            }
+            WorldBorderCompatibility.setWarningTimeDuration(worldBorder, duration);
             issuer.sendMessage(MVCorei18n.WORLDBORDER_WARNINGTIME_SUCCESS,
-                    replace("{time}").with(worldBorder.getWarningTime()),
+                    replace("{time}").with(String.format("%.2f", WorldBorderCompatibility.getWarningTime(worldBorder))),
                     Replace.WORLD.with(world.getAliasOrName()));
         });
     }
 
+    private void setRoundOffError(MVCommandIssuer issuer, TickDuration duration) {
+        issuer.sendError(MVCorei18n.WORLDBORDER_ROUNDOFF_WARNING,
+                replace("{fromTime}").with(String.format("%.2f", duration.toSeconds())),
+                replace("{toTime}").with(Math.round(duration.toSeconds())));
+    }
+
     private void worldBorderAction(MVCommandIssuer issuer, LoadedMultiverseWorld world, Consumer<WorldBorder> worldBorderAction) {
         Try.run(() -> world.getWorldBorder().peek(worldBorderAction))
                 .onFailure(error -> issuer.sendError(error.getLocalizedMessage()));

src/main/java/org/mvplugins/multiverse/core/config/CoreConfig.java

@@ -186,6 +186,16 @@ public final class CoreConfig {
         return configHandle.get(configNodes.enforceFlight);
     }
 
+    @ApiStatus.AvailableSince("5.5")
+    public Try<Void> setGamemodeAndFlightEnforceDelay(int delayTicks) {
+        return configHandle.set(configNodes.gamemodeAndFlightEnforceDelay, delayTicks);
+    }
+
+    @ApiStatus.AvailableSince("5.5")
+    public int getGamemodeAndFlightEnforceDelay() {
+        return configHandle.get(configNodes.gamemodeAndFlightEnforceDelay);
+    }
+
     @ApiStatus.AvailableSince("5.3")
     public Try<Void> setApplyEntitySpawnRate(boolean applyEntitySpawnRate) {
         return configHandle.set(configNodes.applyEntitySpawnRate, applyEntitySpawnRate);
@@ -493,6 +503,26 @@ public final class CoreConfig {
         return configHandle.get(configNodes.registerPapiHook);
     }
 
+    @ApiStatus.AvailableSince("5.5")
+    public Try<Void> setWarnInvalidPapiFormat(boolean warnInvalidPapiFormat) {
+        return configHandle.set(configNodes.warnInvalidPapiFormat, warnInvalidPapiFormat);
+    }
+
+    @ApiStatus.AvailableSince("5.5")
+    public boolean getWarnInvalidPapiFormat() {
+        return configHandle.get(configNodes.warnInvalidPapiFormat);
+    }
+
+    @ApiStatus.AvailableSince("5.5")
+    public Try<Void> setInvalidPapiFormatReturnsBlank(boolean invalidPapiFormatReturnsBlank) {
+        return configHandle.set(configNodes.invalidPapiFormatReturnsBlank, invalidPapiFormatReturnsBlank);
+    }
+
+    @ApiStatus.AvailableSince("5.5")
+    public  boolean getInvalidPapiFormatReturnsBlank() {
+        return configHandle.get(configNodes.invalidPapiFormatReturnsBlank);
+    }
+
     /**
      * {@inheritDoc}
      */
@@ -621,6 +651,16 @@ public final class CoreConfig {
         return configHandle.get(configNodes.eventPriorityPlayerTeleport);
     }
 
+    @ApiStatus.AvailableSince("5.5")
+    public Try<Void> setEventPriorityPlayerWorldChange(EventPriority eventPriorityPlayerWorldChange) {
+        return configHandle.set(configNodes.eventPriorityPlayerWorldChange, eventPriorityPlayerWorldChange);
+    }
+
+    @ApiStatus.AvailableSince("5.5")
+    public EventPriority getEventPriorityPlayerWorldChange() {
+        return configHandle.get(configNodes.eventPriorityPlayerWorldChange);
+    }
+
     public Try<Void> setBukkitYmlPath(String bukkitYmlPath) {
         return configHandle.set(configNodes.bukkitYmlPath, bukkitYmlPath);
     }

src/main/java/org/mvplugins/multiverse/core/config/CoreConfigNodes.java

@@ -135,6 +135,16 @@ final class CoreConfigNodes {
             .name("enforce-flight")
             .build());
 
+    final ConfigNode<Integer> gamemodeAndFlightEnforceDelay = node(ConfigNode.builder("world.gamemode-and-flight-enforce-delay", Integer.class)
+            .comment("")
+            .comment("Sets the delay in ticks before Multiverse enforces gamemode and flight ability on world change.")
+            .comment("Increase this value if you are experiencing issues with other plugins overriding gamemode or flight ability.")
+            .comment("Or set to 0 to enforce immediately during world change event.")
+            .defaultValue(1)
+            .name("gamemode-and-flight-enforce-delay")
+            .suggester((sender -> List.of("0", "1", "2", "5", "10")))
+            .build());
+
     final ConfigNode<Boolean> applyEntitySpawnRate = node(ConfigNode.builder("world.apply-entity-spawn-rate", Boolean.class)
             .comment("")
             .comment("Sets whether Multiverse will apply the world's entity `tick-rate` config in worlds.yml.")
@@ -210,7 +220,10 @@ final class CoreConfigNodes {
 
     final ConfigNode<PassengerModes> passengerMode = node(ConfigNode.builder("teleport.passenger-mode", PassengerModes.class)
             .comment("")
-            .comment("Configures how passengers and vehicles are handled when an entity is teleported.")
+            .comment("Configures how passengers and vehicles are handled when an entity is teleported. This config is")
+            .comment("only applied to /mvtp, join-destination and first-spawn-override. It will not touch any other")
+            .comment("teleport by other plugins or commands.")
+            .comment("========= Available options: =========")
             .comment("  default: Server will handle passengers and vehicles. On papermc 1.21.10+, all will be retained by default.")
             .comment("                                                       On older versions, all will be dismounted if world changes.")
             .comment("  dismount_passengers: Passengers will be removed from the parent entity before the teleport.")
@@ -390,6 +403,23 @@ final class CoreConfigNodes {
             .name("register-papi-hook")
             .build());
 
+    final ConfigNode<Boolean> warnInvalidPapiFormat = node(ConfigNode.builder("messaging.warn-invalid-papi-format", Boolean.class)
+            .comment("")
+            .comment("This config option defines whether or not Multiverse should warn about invalid PlaceholderAPI formats.")
+            .comment("Only applies if PlaceholderAPI is installed, and only to multiverse placeholders.")
+            .defaultValue(true)
+            .name("warn-invalid-papi-format")
+            .build());
+
+    final ConfigNode<Boolean> invalidPapiFormatReturnsBlank = node(ConfigNode.builder("messaging.invalid-papi-format-returns-blank", Boolean.class)
+            .comment("")
+            .comment("By default, invalid formats will return the original placeholder string.")
+            .comment("This config option defines whether or not Multiverse should show invalid PlaceholderAPI formats as blank.")
+            .comment("Only applies if PlaceholderAPI is installed, and only to multiverse placeholders.")
+            .defaultValue(false)
+            .name("invalid-papi-format-returns-blank")
+            .build());
+
     final ConfigNode<Locale> defaultLocale = node(ConfigNode.builder("messaging.default-locale", Locale.class)
             .comment("")
             .comment("This config option defines the default language Multiverse should use.")
@@ -528,6 +558,18 @@ final class CoreConfigNodes {
                             "full effect after a server restart."))
             .build());
 
+    final ConfigNode<EventPriority> eventPriorityPlayerWorldChange = node(ConfigNode.builder("event-priority.player-changed-world", EventPriority.class)
+            .defaultValue(EventPriority.NORMAL)
+            .name("event-priority-player-changed-world")
+            .comment("")
+            .comment("This config option defines the priority for the PlayerChangedWorldEvent.")
+            .onLoadAndChange((oldValue, newValue) ->
+                    eventPriorityMapper.get().setPriority("mvcore-player-changed-world", newValue))
+            .onChange((sender, oldValue, newValue) ->
+                    sender.sendMessage(ChatColor.YELLOW + "'event-priority.player-changed-world' config option will only take " +
+                            "full effect after a server restart."))
+            .build());
+
     private final ConfigHeaderNode miscHeader = node(ConfigHeaderNode.builder("misc")
             .comment("")
             .comment("")

src/main/java/org/mvplugins/multiverse/core/config/handle/BaseConfigurationHandle.java

@@ -3,11 +3,9 @@ package org.mvplugins.multiverse.core.config.handle;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
-import java.util.Objects;
 import java.util.logging.Logger;
 
 import com.dumptruckman.minecraft.util.Logging;
-import io.vavr.control.Option;
 import io.vavr.control.Try;
 import org.bukkit.Bukkit;
 import org.bukkit.command.CommandSender;
@@ -19,6 +17,7 @@ import org.jetbrains.annotations.Nullable;
 
 import org.mvplugins.multiverse.core.config.migration.ConfigMigrator;
 import org.mvplugins.multiverse.core.config.node.ListValueNode;
+import org.mvplugins.multiverse.core.config.node.MapValueNode;
 import org.mvplugins.multiverse.core.config.node.NodeGroup;
 import org.mvplugins.multiverse.core.config.node.ValueNode;
 
@@ -93,17 +92,13 @@ public abstract class BaseConfigurationHandle<C extends ConfigurationSection> {
     }
 
     protected <T> T deserializeNodeFromConfig(ValueNode<T> node) {
-        if (node.getSerializer() == null) {
-            return Option.of(config.getObject(node.getPath(), node.getType())).getOrElse(node::getDefaultValue);
-        }
         return Try.of(() -> {
                     var value = config.get(node.getPath());
-                    if (value == null) {
-                        return node.getDefaultValue();
-                    }
-                    return node.getSerializer().deserialize(value, node.getType());
-                }).flatMap(value -> node.validate(value).map(ignore -> value))
-                .onFailure(e -> Logging.warning("Failed to deserialize node %s: %s", node.getPath(), e.getMessage()))
+                    return value == null ? node.getDefaultValue() : node.deserialize(value);
+                })
+                .flatMap(value -> node.validate(value).map(ignore -> value))
+                .onFailure(e -> Logging.warning("Failed to deserialize node %s: %s",
+                        node.getPath(), e.getMessage()))
                 .getOrElse(node::getDefaultValue);
     }
 
@@ -124,12 +119,7 @@ public abstract class BaseConfigurationHandle<C extends ConfigurationSection> {
         if (value == null) {
             value = node.getDefaultValue();
         }
-        if (node.getSerializer() != null) {
-            var serialized = node.getSerializer().serialize(value, node.getType());
-            config.set(node.getPath(), serialized);
-        } else {
-            config.set(node.getPath(), value);
-        }
+        config.set(node.getPath(), node.serialize(value));
     }
 
     /**
@@ -163,6 +153,15 @@ public abstract class BaseConfigurationHandle<C extends ConfigurationSection> {
         return set(Bukkit.getConsoleSender(), node, value);
     }
 
+    public <K, V> Try<Void> set(@NotNull MapValueNode<K, V> node, K key, V value) {
+        return node.validateEntry(key, value).map(ignore -> {
+            Map<K,V> map = get(node);
+            map.put(key, value);
+            // node.onSetEntryValue(null, key, null, value);
+            return null;
+        });
+    }
+
     /**
      * Sets the value of a node, if the validator is not null, it will be tested first.
      *
@@ -221,6 +220,18 @@ public abstract class BaseConfigurationHandle<C extends ConfigurationSection> {
         });
     }
 
+    public <K, V> Try<Void> remove(@NotNull MapValueNode<K, V> node, K key) {
+        return node.validateKey(key).map(ignore -> {
+            Map<K,V> map = get(node);
+            V value = map.remove(key);
+            if (value == null) {
+                throw new IllegalArgumentException("Cannot remove entry as it is already not in the map!");
+            }
+            // node.onSetEntryValue(key, value, null);
+            return null;
+        });
+    }
+
     /**
      * Sets the default value of a node.
      *

src/main/java/org/mvplugins/multiverse/core/config/handle/FileConfigurationHandle.java

@@ -112,10 +112,5 @@ public abstract class FileConfigurationHandle<C extends FileConfiguration> exten
          * @return The configuration handle.
          */
         public abstract @NotNull FileConfigurationHandle<C> build();
-
-        @SuppressWarnings("unchecked")
-        protected B self() {
-            return (B) this;
-        }
     }
 }

src/main/java/org/mvplugins/multiverse/core/config/node/ConfigNode.java

@@ -180,6 +180,24 @@ public class ConfigNode<T> extends ConfigHeaderNode implements ValueNode<T> {
         return serializer;
     }
 
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public T deserialize(@Nullable Object object) {
+        return serializer == null
+                ? (type.isInstance(object)) ? type.cast(object) : getDefaultValue()
+                : serializer.deserialize(object, type);
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public Object serialize(T value) {
+        return serializer ==  null ? value : serializer.serialize(value, type);
+    }
+
     /**
      * {@inheritDoc}
      */

src/main/java/org/mvplugins/multiverse/core/config/node/ListConfigNode.java

@@ -120,9 +120,9 @@ public class ListConfigNode<I> extends ConfigNode<List<I>> implements ListValueN
     private void setDefaultSuggester() {
         if (itemSuggester instanceof SenderNodeSuggester senderItemSuggester) {
             this.suggester = (SenderNodeSuggester)(sender, input) ->
-                    StringFormatter.addonToCommaSeperated(input, senderItemSuggester.suggest(sender, input));
+                    StringFormatter.addOnToCommaSeparated(input, senderItemSuggester.suggest(sender, input));
         } else {
-            this.suggester = input -> StringFormatter.addonToCommaSeperated(input, itemSuggester.suggest(input));
+            this.suggester = input -> StringFormatter.addOnToCommaSeparated(input, itemSuggester.suggest(input));
         }
     }
 
@@ -283,7 +283,7 @@ public class ListConfigNode<I> extends ConfigNode<List<I>> implements ListValueN
             //noinspection unchecked
             super(path, (Class<List<I>>) (Object) List.class);
             this.itemType = itemType;
-            this.defaultValue = () -> (List<I>) new ArrayList<>();
+            this.defaultValue = ArrayList::new;
         }
 
         /**

src/main/java/org/mvplugins/multiverse/core/config/node/MapConfigNode.java

@@ -0,0 +1,603 @@
+package org.mvplugins.multiverse.core.config.node;
+
+import com.dumptruckman.minecraft.util.Logging;
+import io.vavr.control.Try;
+import org.bukkit.command.CommandSender;
+import org.bukkit.configuration.ConfigurationSection;
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+import org.mvplugins.multiverse.core.config.node.functions.DefaultStringParserProvider;
+import org.mvplugins.multiverse.core.config.node.functions.DefaultSuggesterProvider;
+import org.mvplugins.multiverse.core.config.node.functions.NodeChangeCallback;
+import org.mvplugins.multiverse.core.config.node.functions.NodeStringParser;
+import org.mvplugins.multiverse.core.config.node.functions.NodeSuggester;
+import org.mvplugins.multiverse.core.config.node.functions.NodeValueCallback;
+import org.mvplugins.multiverse.core.config.node.functions.SenderNodeStringParser;
+import org.mvplugins.multiverse.core.config.node.functions.SenderNodeSuggester;
+import org.mvplugins.multiverse.core.config.node.serializer.DefaultSerializerProvider;
+import org.mvplugins.multiverse.core.config.node.serializer.NodeSerializer;
+import org.mvplugins.multiverse.core.exceptions.MultiverseException;
+import org.mvplugins.multiverse.core.utils.REPatterns;
+
+import java.util.Collection;
+import java.util.Collections;
+import java.util.LinkedHashMap;
+import java.util.Map;
+import java.util.Objects;
+import java.util.function.Function;
+import java.util.function.Supplier;
+
+/**
+ * A config node that contains key-value mappings.
+ *
+ * @param <K> The key type.
+ * @param <V> The value type.
+ *
+ * @since 5.7
+ */
+@ApiStatus.AvailableSince("5.7")
+public class MapConfigNode<K, V> extends ConfigNode<Map<K, V>> implements MapValueNode<K, V> {
+
+    /**
+     * Creates a new builder for a {@link MapConfigNode}.
+     *
+     * @param path      The path of the node.
+     * @param keyType   The map key type.
+     * @param valueType The map value type.
+     * @param <K>       The key type.
+     * @param <V>       The value type.
+     * @return The new builder.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static @NotNull <K, V> Builder<K, V> mapBuilder(
+            @NotNull String path,
+            @NotNull Class<K> keyType,
+            @NotNull Class<V> valueType) {
+        return new Builder<>(path, keyType, valueType);
+    }
+
+    protected final @NotNull Class<K> keyType;
+    protected final @NotNull Class<V> valueType;
+    protected final @Nullable NodeSuggester keySuggester;
+    protected final @Nullable NodeSuggester valueSuggester;
+    protected final @Nullable NodeStringParser<K> keyStringParser;
+    protected final @Nullable NodeStringParser<V> valueStringParser;
+    protected final @Nullable NodeSerializer<K> keySerializer;
+    protected final @Nullable NodeSerializer<V> valueSerializer;
+    protected final @Nullable Function<K, Try<Void>> keyValidator;
+    protected final @Nullable Function<V, Try<Void>> valueValidator;
+
+    protected MapConfigNode(
+            @NotNull String path,
+            @NotNull String[] comments,
+            @Nullable String name,
+            @NotNull Class<Map<K, V>> type,
+            @NotNull String[] aliases,
+            @Nullable Supplier<Map<K, V>> defaultValueSupplier,
+            @Nullable NodeSuggester suggester,
+            @Nullable NodeStringParser<Map<K, V>> stringParser,
+            @Nullable NodeSerializer<Map<K, V>> serializer,
+            @Nullable Function<Map<K, V>, Try<Void>> validator,
+            @Nullable NodeValueCallback<Map<K, V>> onLoad,
+            @Nullable NodeChangeCallback<Map<K, V>> onLoadAndChange,
+            @Nullable NodeChangeCallback<Map<K, V>> onChange,
+            @NotNull Class<K> keyType,
+            @NotNull Class<V> valueType,
+            @Nullable NodeSuggester keySuggester,
+            @Nullable NodeSuggester valueSuggester,
+            @Nullable NodeStringParser<K> keyStringParser,
+            @Nullable NodeStringParser<V> valueStringParser,
+            @Nullable NodeSerializer<K> keySerializer,
+            @Nullable NodeSerializer<V> valueSerializer,
+            @Nullable Function<K, Try<Void>> keyValidator,
+            @Nullable Function<V, Try<Void>> valueValidator) {
+        super(path, comments, name, type, aliases, defaultValueSupplier, suggester, stringParser, serializer,
+                validator, onLoad, onLoadAndChange, onChange);
+        this.keyType = keyType;
+        this.valueType = valueType;
+        this.keySuggester = keySuggester != null
+                ? keySuggester
+                : DefaultSuggesterProvider.getDefaultSuggester(keyType);
+        this.valueSuggester = valueSuggester != null
+                ? valueSuggester
+                : DefaultSuggesterProvider.getDefaultSuggester(valueType);
+        this.keyStringParser = keyStringParser != null
+                ? keyStringParser
+                : DefaultStringParserProvider.getDefaultStringParser(keyType);
+        this.valueStringParser = valueStringParser != null
+                ? valueStringParser
+                : DefaultStringParserProvider.getDefaultStringParser(valueType);
+        this.keySerializer = keySerializer != null
+                ? keySerializer
+                : DefaultSerializerProvider.getDefaultSerializer(keyType);
+        this.valueSerializer = valueSerializer != null
+                ? valueSerializer
+                : DefaultSerializerProvider.getDefaultSerializer(valueType);
+        this.keyValidator = keyValidator != null
+                ? keyValidator
+                : defaultYamlKeyValidator();
+        this.valueValidator = valueValidator;
+
+        setDefaults();
+    }
+
+    private Function<K, Try<Void>> defaultYamlKeyValidator() {
+        return key -> Try.of(() -> {
+            if (!REPatterns.YAML_KEY.matcher(String.valueOf(serializeKey(key))).matches()) {
+                throw new MultiverseException("Invalid yaml key: '" + key + "'. Keys can only " +
+                        "contain alphanumeric characters, underscores and hyphens.");
+            }
+            return null;
+        });
+    }
+
+    private void setDefaults() {
+        if ((this.keySuggester != null || this.valueSuggester != null) && this.suggester == null) {
+            setDefaultSuggester();
+        }
+        if (this.keyStringParser != null && this.valueStringParser != null && this.stringParser == null) {
+            setDefaultStringParser();
+        }
+        if ((this.keyValidator != null || this.valueValidator != null) && this.validator == null) {
+            setDefaultValidator();
+        }
+        if ((this.keySerializer != null || this.valueSerializer != null) && this.serializer == null) {
+            setDefaultSerializer();
+        }
+        if (this.defaultValue == null) {
+            this.defaultValue = LinkedHashMap::new;
+        }
+    }
+
+    private void setDefaultSuggester() {
+        if (this.keySuggester instanceof SenderNodeSuggester || this.valueSuggester instanceof SenderNodeSuggester) {
+            this.suggester = (SenderNodeSuggester) this::suggestEntries;
+        } else {
+            this.suggester = input -> suggestEntries(null, input);
+        }
+    }
+
+    private @NotNull Collection<String> suggestEntries(@Nullable CommandSender sender, @Nullable String input) {
+        String content = input == null ? "" : input;
+        int lastComma = content.lastIndexOf(',');
+        String prefix = lastComma == -1 ? "" : content.substring(0, lastComma + 1);
+        String currentEntry = lastComma == -1 ? content : content.substring(lastComma + 1);
+
+        String[] keyValue = REPatterns.EQUALS.split(currentEntry, 2);
+        if (keyValue.length == 2 && valueSuggester != null) {
+            String keyPart = keyValue[0];
+            String valuePart = keyValue[1];
+            return suggestFrom(valueSuggester, sender, valuePart).stream()
+                    .map(suggestedValue -> prefix + keyPart + "=" + suggestedValue)
+                    .toList();
+        }
+
+        if (keySuggester == null) {
+            return Collections.emptyList();
+        }
+
+        return suggestFrom(keySuggester, sender, currentEntry).stream()
+                .map(suggestedKey -> prefix + suggestedKey + "=")
+                .toList();
+    }
+
+    private @NotNull Collection<String> suggestFrom(
+            @NotNull NodeSuggester suggester,
+            @Nullable CommandSender sender,
+            @Nullable String input) {
+        if (sender != null && suggester instanceof SenderNodeSuggester senderSuggester) {
+            return senderSuggester.suggest(sender, input);
+        }
+        return suggester.suggest(input);
+    }
+
+    private void setDefaultStringParser() {
+        this.stringParser = (input, type) -> Try.of(() -> {
+            Map<K, V> parsed = new LinkedHashMap<>();
+            if (input == null || input.isBlank()) {
+                return parsed;
+            }
+            for (String entry : REPatterns.SEMICOLON.split(input)) {
+                String[] keyValue = REPatterns.EQUALS.split(entry, 2);
+                if (keyValue.length != 2) {
+                    throw new IllegalArgumentException("Invalid map entry '" + entry + "'. Expected format key=value");
+                }
+                NodeStringParser<K> keyParser = Objects.requireNonNull(keyStringParser, "keyStringParser");
+                NodeStringParser<V> valueParser = Objects.requireNonNull(valueStringParser, "valueStringParser");
+                K parsedKey = keyParser.parse(keyValue[0].trim(), keyType).get();
+                V parsedValue = valueParser.parse(keyValue[1].trim(), valueType).get();
+                parsed.put(parsedKey, parsedValue);
+            }
+            return parsed;
+        });
+    }
+
+    private void setDefaultValidator() {
+        this.validator = value -> Try.of(() -> {
+            if (value == null) {
+                return null;
+            }
+            for (Map.Entry<K, V> entry : value.entrySet()) {
+                if (keyValidator != null) {
+                    keyValidator.apply(entry.getKey()).get();
+                }
+                if (valueValidator != null) {
+                    valueValidator.apply(entry.getValue()).get();
+                }
+            }
+            return null;
+        });
+    }
+
+    private void setDefaultSerializer() {
+        this.serializer = new NodeSerializer<>() {
+            @Override
+            public Map<K, V> deserialize(Object object, Class<Map<K, V>> type) {
+                if (object == null) {
+                    return new LinkedHashMap<>();
+                }
+
+                if (object instanceof Map<?, ?> rawMap) {
+                    Map<K, V> result = new LinkedHashMap<>();
+                    rawMap.forEach((key, value) -> {
+                        Map.Entry<K, V> entry = deserializeEntry(key, value);
+                        result.put(entry.getKey(), entry.getValue());
+                    });
+                    return result;
+                }
+
+                if (object instanceof ConfigurationSection section) {
+                    Map<K, V> result = new LinkedHashMap<>();
+                    for (String key : section.getKeys(false)) {
+                        Object rawValue = section.get(key);
+                        Map.Entry<K, V> entry = deserializeEntry(key, rawValue);
+                        result.put(entry.getKey(), entry.getValue());
+                    }
+                    return result;
+                }
+
+                throw new IllegalArgumentException("Invalid map object '" + object + "'. Expected map or section.");
+            }
+
+            @Override
+            public Object serialize(Map<K, V> object, Class<Map<K, V>> type) {
+                Map<Object, Object> serialized = new LinkedHashMap<>();
+                if (object == null) {
+                    return serialized;
+                }
+                object.forEach((key, value) -> {
+                    Map.Entry<Object, Object> entry = serializeEntry(key, value);
+                    serialized.put(entry.getKey(), entry.getValue());
+                });
+                return serialized;
+            }
+        };
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public @NotNull Try<Void> validateKey(@Nullable K key) {
+        return keyValidator == null ? Try.success(null) : keyValidator.apply(key);
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public @NotNull Try<Void> validateValue(@Nullable V value) {
+        return valueValidator == null ? Try.success(null) : valueValidator.apply(value);
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public @NotNull Try<Void> validateEntry(@Nullable K key, @Nullable V value) {
+        return validateKey(key).flatMap(ignored -> validateValue(value));
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public @NotNull Map.Entry<K, V> deserializeEntry(@Nullable Object key, @Nullable Object value) {
+        K deserializedKey = keySerializer == null
+                ? keyType.isInstance(key) ? keyType.cast(key) : null
+                : keySerializer.deserialize(key, keyType);
+        V deserializedValue = valueSerializer == null
+                ? keyType.isInstance(value) ? valueType.cast(value) : null
+                : valueSerializer.deserialize(value, valueType);
+        return new SimpleEntry<>(deserializedKey, deserializedValue);
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public @NotNull Map.Entry<Object, Object> serializeEntry(@Nullable K key, @Nullable V value) {
+        return new SimpleEntry<>(serializeKey(key), serializeValue(value));
+    }
+
+    private @Nullable Object serializeKey(@Nullable K key) {
+        return keySerializer == null ? key : keySerializer.serialize(key, keyType);
+    }
+
+    private @Nullable Object serializeValue(@Nullable V value) {
+        return valueSerializer == null ? value : valueSerializer.serialize(value, valueType);
+    }
+
+    private record SimpleEntry<K, V>(K key, V value) implements Map.Entry<K, V> {
+        @Override
+        public K getKey() {
+            return key;
+        }
+
+        @Override
+        public V getValue() {
+            return value;
+        }
+
+        @Override
+        public V setValue(V value) {
+            throw new UnsupportedOperationException();
+        }
+    }
+
+    /**
+     * Builder for {@link MapConfigNode} instances.
+     *
+     * <p>This builder extends {@link ConfigNode.Builder} with additional configuration specific to map entries:
+     * entry-level suggesters, string parsers, serializers and validators for both keys and values. When any
+     * entry-level component is omitted the builder provides a sensible default (for example default parsers,
+     * suggesters, serializers or an empty map default value).
+     *
+     * @param <K> The map key type.
+     * @param <V> The map value type.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static class Builder<K, V> extends ConfigNode.Builder<Map<K, V>, Builder<K, V>> {
+
+        protected final @NotNull Class<K> keyType;
+        protected final @NotNull Class<V> valueType;
+        protected @Nullable NodeSuggester keySuggester;
+        protected @Nullable NodeSuggester valueSuggester;
+        protected @Nullable NodeStringParser<K> keyStringParser;
+        protected @Nullable NodeStringParser<V> valueStringParser;
+        protected @Nullable NodeSerializer<K> keySerializer;
+        protected @Nullable NodeSerializer<V> valueSerializer;
+        protected @Nullable Function<K, Try<Void>> keyValidator;
+        protected @Nullable Function<V, Try<Void>> valueValidator;
+
+        /**
+         * Creates a new builder for a map config node.
+         *
+         * @param path The configuration path for the node.
+         * @param keyType The runtime type of the map keys.
+         * @param valueType The runtime type of the map values.
+         *
+         * @since 5.7
+         */
+        @ApiStatus.AvailableSince("5.7")
+        protected Builder(@NotNull String path, @NotNull Class<K> keyType, @NotNull Class<V> valueType) {
+            //noinspection unchecked
+            super(path, (Class<Map<K, V>>) (Object) Map.class);
+            this.keyType = keyType;
+            this.valueType = valueType;
+            this.defaultValue = LinkedHashMap::new;
+        }
+
+        /**
+         * Sets a suggester for map keys. The suggester is used when computing tab-completion suggestions for the
+         * key part of an entry.
+         *
+         * @param keySuggester The suggester to use for keys.
+         * @return This builder for chaining.
+         *
+         * @since 5.7
+         */
+        @ApiStatus.AvailableSince("5.7")
+        public @NotNull Builder<K, V> keySuggester(@NotNull NodeSuggester keySuggester) {
+            this.keySuggester = keySuggester;
+            return self();
+        }
+
+        /**
+         * Sets a sender-aware suggester for map keys. Use this when suggestions depend on the command sender
+         * (permissions, location, etc.).
+         *
+         * @param keySuggester The sender-aware suggester.
+         * @return This builder for chaining.
+         *
+         * @since 5.7
+         */
+        @ApiStatus.AvailableSince("5.7")
+        public @NotNull Builder<K, V> keySuggester(@NotNull SenderNodeSuggester keySuggester) {
+            this.keySuggester = keySuggester;
+            return self();
+        }
+
+        /**
+         * Sets a suggester for map values. The suggester is used when computing tab-completion suggestions for the
+         * value part of an entry.
+         *
+         * @param valueSuggester The suggester to use for values.
+         * @return This builder for chaining.
+         *
+         * @since 5.7
+         */
+        @ApiStatus.AvailableSince("5.7")
+        public @NotNull Builder<K, V> valueSuggester(@NotNull NodeSuggester valueSuggester) {
+            this.valueSuggester = valueSuggester;
+            return self();
+        }
+
+        /**
+         * Sets a sender-aware suggester for map values. Use this when value suggestions depend on the
+         * command sender.
+         *
+         * @param valueSuggester The sender-aware suggester.
+         * @return This builder for chaining.
+         *
+         * @since 5.7
+         */
+        @ApiStatus.AvailableSince("5.7")
+        public @NotNull Builder<K, V> valueSuggester(@NotNull SenderNodeSuggester valueSuggester) {
+            this.valueSuggester = valueSuggester;
+            return self();
+        }
+
+        /**
+         * Sets the string parser for keys. The parser is used when parsing user-provided key strings into key
+         * instances (e.g. when parsing a map from a single-line string representation).
+         *
+         * @param keyStringParser The parser to use for keys.
+         * @return This builder for chaining.
+         *
+         * @since 5.7
+         */
+        @ApiStatus.AvailableSince("5.7")
+        public @NotNull Builder<K, V> keyStringParser(@NotNull NodeStringParser<K> keyStringParser) {
+            this.keyStringParser = keyStringParser;
+            return self();
+        }
+
+        /**
+         * Sets a sender-aware string parser for keys. Use this when parsing depends on the sender context.
+         *
+         * @param keyStringParser The sender-aware key parser.
+         * @return This builder for chaining.
+         *
+         * @since 5.7
+         */
+        @ApiStatus.AvailableSince("5.7")
+        public @NotNull Builder<K, V> keyStringParser(@NotNull SenderNodeStringParser<K> keyStringParser) {
+            this.keyStringParser = keyStringParser;
+            return self();
+        }
+
+        /**
+         * Sets the string parser for values. The parser converts the textual part after '=' in an entry into the
+         * value type.
+         *
+         * @param valueStringParser The parser to use for values.
+         * @return This builder for chaining.
+         *
+         * @since 5.7
+         */
+        @ApiStatus.AvailableSince("5.7")
+        public @NotNull Builder<K, V> valueStringParser(@NotNull NodeStringParser<V> valueStringParser) {
+            this.valueStringParser = valueStringParser;
+            return self();
+        }
+
+        /**
+         * Sets a sender-aware string parser for values.
+         *
+         * @param valueStringParser The sender-aware value parser.
+         * @return This builder for chaining.
+         *
+         * @since 5.7
+         */
+        @ApiStatus.AvailableSince("5.7")
+        public @NotNull Builder<K, V> valueStringParser(@NotNull SenderNodeStringParser<V> valueStringParser) {
+            this.valueStringParser = valueStringParser;
+            return self();
+        }
+
+        /**
+         * Sets the serializer for keys. Serializers convert keys to/from persisted forms stored in the configuration
+         * backend.
+         *
+         * @param keySerializer The key serializer.
+         * @return This builder for chaining.
+         *
+         * @since 5.7
+         */
+        @ApiStatus.AvailableSince("5.7")
+        public @NotNull Builder<K, V> keySerializer(@NotNull NodeSerializer<K> keySerializer) {
+            this.keySerializer = keySerializer;
+            return self();
+        }
+
+        /**
+         * Sets the serializer for values.
+         *
+         * @param valueSerializer The value serializer.
+         * @return This builder for chaining.
+         *
+         * @since 5.7
+         */
+        @ApiStatus.AvailableSince("5.7")
+        public @NotNull Builder<K, V> valueSerializer(@NotNull NodeSerializer<V> valueSerializer) {
+            this.valueSerializer = valueSerializer;
+            return self();
+        }
+
+        /**
+         * Sets a validator for keys. The validator should return a successful {@link Try} for valid keys or a failed
+         * {@link Try} describing the validation error for invalid keys.
+         *
+         * @param keyValidator The key validator.
+         * @return This builder for chaining.
+         *
+         * @since 5.7
+         */
+        @ApiStatus.AvailableSince("5.7")
+        public @NotNull Builder<K, V> keyValidator(@NotNull Function<K, Try<Void>> keyValidator) {
+            this.keyValidator = keyValidator;
+            return self();
+        }
+
+        /**
+         * Sets a validator for values.
+         *
+         * @param valueValidator The value validator.
+         * @return This builder for chaining.
+         *
+         * @since 5.7
+         */
+        @ApiStatus.AvailableSince("5.7")
+        public @NotNull Builder<K, V> valueValidator(@NotNull Function<V, Try<Void>> valueValidator) {
+            this.valueValidator = valueValidator;
+            return self();
+        }
+
+        /**
+         * {@inheritDoc}
+         */
+        @Override
+        public @NotNull MapConfigNode<K, V> build() {
+            return new MapConfigNode<>(
+                    path,
+                    comments.toArray(new String[0]),
+                    name,
+                    type,
+                    aliases,
+                    defaultValue,
+                    suggester,
+                    stringParser,
+                    serializer,
+                    validator,
+                    onLoad,
+                    onLoadAndChange,
+                    onChange,
+                    keyType,
+                    valueType,
+                    keySuggester,
+                    valueSuggester,
+                    keyStringParser,
+                    valueStringParser,
+                    keySerializer,
+                    valueSerializer,
+                    keyValidator,
+                    valueValidator);
+        }
+    }
+}

src/main/java/org/mvplugins/multiverse/core/config/node/MapValueNode.java

@@ -0,0 +1,93 @@
+package org.mvplugins.multiverse.core.config.node;
+
+import io.vavr.control.Try;
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.Map;
+
+/**
+ * A {@link ValueNode} specialization that stores a {@link Map} of key-value pairs.
+ *
+ * @param <K> The key type.
+ * @param <V> The value type.
+ *
+ * @since 5.7
+ */
+@ApiStatus.AvailableSince("5.7")
+public interface MapValueNode<K, V> extends ValueNode<Map<K, V>> {
+
+    /**
+     * Validates a single map key.
+     * <br />
+     * Implementations should return a successful {@link Try} when the key is acceptable, or a failed
+     * {@link Try} when the key is invalid.
+     *
+     * @param key The key to validate, or {@code null} if the key is absent.
+     * @return A successful {@link Try} if the key is valid, or a failed {@link Try} if it is not.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    @NotNull Try<Void> validateKey(@Nullable K key);
+
+    /**
+     * Validates a single map value.
+     * <br />
+     * Implementations should return a successful {@link Try} when the value is acceptable, or a failed
+     * {@link Try} when the value is invalid.
+     *
+     * @param value The value to validate, or {@code null} if the value is absent.
+     * @return A successful {@link Try} if the value is valid, or a failed {@link Try} if it is not.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    @NotNull Try<Void> validateValue(@Nullable V value);
+
+    /**
+     * Validates a key-value entry.
+     * <br />
+     * This is typically implemented by composing {@link #validateKey(Object)} and {@link #validateValue(Object)}.
+     * If either part fails, the entry is considered invalid.
+     *
+     * @param key The entry key, or {@code null} if the key is absent.
+     * @param value The entry value, or {@code null} if the value is absent.
+     * @return A successful {@link Try} if both parts are valid, or a failed {@link Try} if either part is invalid.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    @NotNull Try<Void> validateEntry(@Nullable K key, @Nullable V value);
+
+    /**
+     * Deserializes a raw key-value pair into a map entry.
+     * <br />
+     * This method converts a single persisted entry, not the full map. If either component cannot be converted,
+     * implementations may return {@code null} for that side of the entry.
+     *
+     * @param key The raw key object, or {@code null} if no key is present.
+     * @param value The raw value object, or {@code null} if no value is present.
+     * @return A map entry containing the deserialized key and value.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    @NotNull Map.Entry<K, V> deserializeEntry(@Nullable Object key, @Nullable Object value);
+
+    /**
+     * Serializes a map entry into raw configuration objects.
+     * <br />
+     * This method converts a single entry to a persisted representation, not the full map. The returned entry
+     * contains the serialized key and serialized value.
+     *
+     * @param key The entry key, or {@code null} if the key is absent.
+     * @param value The entry value, or {@code null} if the value is absent.
+     * @return A map entry containing the serialized key and value.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    @NotNull Map.Entry<Object, Object> serializeEntry(@Nullable K key, @Nullable V value);
+}

src/main/java/org/mvplugins/multiverse/core/config/node/ValueNode.java

@@ -34,7 +34,7 @@ public interface ValueNode<T> extends Node {
      * Gets the aliases of this node. Serves as shorter or legacy alternatives the {@link #getName()} and must be
      * unique within a node group.
      *
-     * @return The aliases of this node.
+     * @return The aliases of this node, or an empty array if the node has no aliases.
      *
      * @since 5.1
      */
@@ -44,27 +44,36 @@ public interface ValueNode<T> extends Node {
     }
 
     /**
-     * Gets the default value with type {@link T} of the node.
+     * Gets the default value for this node.
      *
-     * @return The default value of the node.
+     * <p>The returned value is used when no explicit value is present or when deserialization falls back to the
+     * node's default. Implementations may return {@code null} to indicate that no default value is available.
+     *
+     * @return The default value of the node, or {@code null} if none is configured.
      */
     @Nullable T getDefaultValue();
 
     /**
-     * Suggests possible string values for this node. Generated based on the current user input.
+     * Suggests possible string values for this node.
      *
-     * @param input The current partial user input
+     * <p>The returned values are based on the current partial user input and should be suitable for command-line
+     * tab completion or other interactive hints.
+     *
+     * @param input The current partial user input, or {@code null} if no input has been typed yet.
      * @return A collection of possible string values.
      */
     @NotNull Collection<String> suggest(@Nullable String input);
 
     /**
-     * Suggests possible string values for this node. Use contextural information from the sender such as
-     * sender name, permissions, or player location for better suggestions.
+     * Suggests possible string values for this node using sender context.
      *
-     * @param sender    The sender context.
-     * @param input     The input string.
-     * @return A collection of possible string values
+     * <p>Implementations may use the sender's name, permissions, or player location to tailor the returned
+     * suggestions. If no sender-specific logic is available, implementations should fall back to
+     * {@link #suggest(String)}.
+     *
+     * @param sender The sender context.
+     * @param input The current partial user input, or {@code null} if no input has been typed yet.
+     * @return A collection of possible string values.
      *
      * @since 5.1
      */
@@ -72,20 +81,25 @@ public interface ValueNode<T> extends Node {
     @NotNull Collection<String> suggest(@NotNull CommandSender sender, @Nullable String input);
 
     /**
-     * Parses the given string into a value of type {@link T}. Used for property set by user input.
+     * Parses the given string into a value of type {@link T}.
      *
-     * @param input The string to parse.
-     * @return The parsed value, or given exception if parsing failed.
+     * <p>This is typically used for values entered by a user or read from configuration text.
+     *
+     * @param input The string to parse, or {@code null} if the source value is absent.
+     * @return The parsed value, or a failed {@link Try} containing the parsing error.
      */
     @NotNull Try<T> parseFromString(@Nullable String input);
 
     /**
      * Parses the given string into a value of type {@link T} with context from the sender.
-     * Used for property set by user input.
      *
-     * @param sender    The sender context.
-     * @param input     The string to parse.
-     * @return The parsed value, or given exception if parsing failed.
+     * <p>Sender-aware implementations may use permissions or other sender-specific information when converting the
+     * input. If no sender-aware parser is available, implementations should fall back to
+     * {@link #parseFromString(String)}.
+     *
+     * @param sender The sender context.
+     * @param input The string to parse, or {@code null} if the source value is absent.
+     * @return The parsed value, or a failed {@link Try} containing the parsing error.
      *
      * @since 5.1
      */
@@ -97,23 +111,59 @@ public interface ValueNode<T> extends Node {
     /**
      * Gets the serializer for this node.
      *
-     * @return  The serializer for this node.
+     * <p>This method exists for backward compatibility while the preferred API is
+     * {@link #serialize(Object)} and {@link #deserialize(Object)}.
+     *
+     * @return The serializer for this node, or {@code null} if none is configured.
+     *
+     * @deprecated Use {@link #serialize(Object)} and {@link #deserialize(Object)} instead.
      */
+    @Deprecated(forRemoval = true, since = "5.7")
+    @ApiStatus.ScheduledForRemoval(inVersion = "6.0")
     @Nullable NodeSerializer<T> getSerializer();
 
+    /**
+     * Deserializes a raw configuration object into a value of type {@link T}.
+     *
+     * <p>The input is typically a value read from YAML or another configuration source. Implementations should
+     * return a sensible fallback, such as {@link #getDefaultValue()}, when the object cannot be converted.
+     *
+     * @param object The raw object to deserialize.
+     * @return The deserialized value, or {@code null} if the object cannot be converted and no fallback exists.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    @Nullable T deserialize(@Nullable Object object);
+
+    /**
+     * Serializes a value of type {@link T} into a configuration-friendly object.
+     *
+     * <p>The returned object should be suitable for persistence in a configuration file.
+     *
+     * @param value The value to serialize.
+     * @return The serialized representation, or {@code null} if the value cannot be serialized.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    @Nullable Object serialize(@Nullable T value);
+
     /**
      * Validates the value of this node.
      *
      * @param value The value to validate.
-     * @return An empty {@link Try} if the value is valid, or a {@link Try} containing an exception if the value is
-     *         invalid.
+     * @return A successful {@link Try} if the value is valid, or a failed {@link Try} containing the validation
+     *         exception if the value is invalid.
      */
     Try<Void> validate(@Nullable T value);
 
     /**
      * Called when the value of this node is loaded by {@link BaseConfigurationHandle#load()}.
      *
-     * @param value The loaded value.
+     * <p>This callback is invoked after the value has been deserialized and validated during a configuration load.
+     *
+     * @param value The loaded value, or {@code null} if the configured value could not be resolved.
      *
      * @since 5.4
      */
@@ -123,9 +173,12 @@ public interface ValueNode<T> extends Node {
     /**
      * Called when the value of this node is loaded or changed.
      *
-     * @param sender   The sender who triggered the change. If triggered by loading or no target sender is specified,
-     *                 it will be the console sender.
-     * @param oldValue The old value, will always be null on load.
+     * <p>This callback is shared by both initial load and subsequent updates. When invoked during a load, the
+     * {@code oldValue} parameter will be {@code null} and the sender will be the console sender.
+     *
+     * @param sender The sender who triggered the change. If triggered by loading or no target sender is specified,
+     *               it will be the console sender.
+     * @param oldValue The previous value, or {@code null} when called during load.
      * @param newValue The new value.
      *
      * @since 5.4
@@ -136,9 +189,11 @@ public interface ValueNode<T> extends Node {
     /**
      * Called when the value of this node is changed by {@link BaseConfigurationHandle#set(ValueNode, Object)}.
      *
-     * @param sender    The sender who changed the value, or console sender if no target sender specified.
-     * @param oldValue  The old value.
-     * @param newValue  The new value.
+     * <p>This callback is only invoked for explicit updates after the value already exists.
+     *
+     * @param sender The sender who changed the value, or the console sender if no target sender was specified.
+     * @param oldValue The old value.
+     * @param newValue The new value.
      *
      * @since 5.4
      */
@@ -148,12 +203,15 @@ public interface ValueNode<T> extends Node {
     /**
      * Called when the value of this node is set.
      *
+     * <p>This is the legacy, senderless form of {@link #onLoadAndChange(CommandSender, Object, Object)}.
+     *
      * @param oldValue The old value.
      * @param newValue The new value.
      *
      * @deprecated Use {@link #onLoadAndChange(CommandSender, Object, Object)} instead.
      */
     @Deprecated(since = "5.4", forRemoval = true)
+    @ApiStatus.ScheduledForRemoval(inVersion = "6.0")
     default void onSetValue(@Nullable T oldValue, @Nullable T newValue) {
         onLoadAndChange(Bukkit.getConsoleSender(), oldValue, newValue);
     }

src/main/java/org/mvplugins/multiverse/core/destination/core/WorldDestination.java

@@ -6,6 +6,7 @@ import co.aikar.locales.MessageKey;
 import co.aikar.locales.MessageKeyProvider;
 import jakarta.inject.Inject;
 import org.bukkit.command.CommandSender;
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.jvnet.hk2.annotations.Service;
@@ -14,13 +15,11 @@ import org.mvplugins.multiverse.core.config.CoreConfig;
 import org.mvplugins.multiverse.core.destination.Destination;
 import org.mvplugins.multiverse.core.destination.DestinationSuggestionPacket;
 import org.mvplugins.multiverse.core.locale.MVCorei18n;
-import org.mvplugins.multiverse.core.locale.message.MessageReplacement;
 import org.mvplugins.multiverse.core.locale.message.MessageReplacement.Replace;
 import org.mvplugins.multiverse.core.teleportation.LocationManipulation;
 import org.mvplugins.multiverse.core.utils.REPatterns;
 import org.mvplugins.multiverse.core.utils.result.Attempt;
 import org.mvplugins.multiverse.core.utils.result.FailureReason;
-import org.mvplugins.multiverse.core.world.LoadedMultiverseWorld;
 import org.mvplugins.multiverse.core.world.MultiverseWorld;
 import org.mvplugins.multiverse.core.world.WorldManager;
 import org.mvplugins.multiverse.core.world.entrycheck.WorldEntryCheckerProvider;
@@ -56,6 +55,19 @@ public final class WorldDestination implements Destination<WorldDestination, Wor
         return "w";
     }
 
+    /**
+     * Directly create a world destination instance for a Multiverse World without any string parsing validation needed.
+     *
+     * @param multiverseWorld   The destination's target world.
+     * @return The destination instance with the target world.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public @NotNull WorldDestinationInstance fromWorld(MultiverseWorld multiverseWorld) {
+        return new WorldDestinationInstance(this, multiverseWorld, null, -1.0f);
+    }
+
     /**
      * {@inheritDoc}
      */

src/main/java/org/mvplugins/multiverse/core/dynamiclistener/DynamicListenerRegistration.java

@@ -35,7 +35,7 @@ public final class DynamicListenerRegistration {
     private static final boolean hasEventExecutorCreate;
 
     static {
-        hasEventExecutorCreate = ReflectHelper.getMethod(EventExecutor.class, "create", Method.class, Class.class) != null;
+        hasEventExecutorCreate = ReflectHelper.hasMethod(EventExecutor.class, "create", Method.class, Class.class);
     }
 
     private final EventPriorityMapper eventPriorityMapper;
@@ -98,18 +98,22 @@ public final class DynamicListenerRegistration {
         }
 
         method.setAccessible(true);
-        Object methodOutput = ReflectHelper.invokeMethod(listener, method);
-        if (!(methodOutput instanceof EventRunnable eventRunnable)) {
-            Logging.warning("Event method %s in %s did not return a SingleEventListener",
-                    method.getName(), listener.getClass().getName());
-            return;
-        }
-        EventExecutor executor = new EventRunnableExecutor<>(eventClass, eventRunnable);
-        EventPriority priority = getDynamicEventPriority(method);
-        boolean ignoreCancelled = isIgnoreIfCancelled(method);
 
-        Logging.finest("Registering dynamic event for %s with priority %s", eventClass.getName(), priority);
-        Bukkit.getPluginManager().registerEvent(eventClass, listener, priority, executor, plugin, ignoreCancelled);
+        ReflectHelper.tryInvokeMethod(listener, method)
+                .onFailure(e -> Logging.warning("Failed to invoke event method %s in %s: $s",
+                        method.getName(), listener.getClass().getName(), e.getMessage()))
+                .filter(EventRunnable.class::isInstance)
+                .onFailure(e -> Logging.warning("Event method %s in %s did not return an EventRunnable instance!",
+                        method.getName(), listener.getClass().getName()))
+                .map(EventRunnable.class::cast)
+                .map(eventRunnable -> new EventRunnableExecutor<>(eventClass, eventRunnable))
+                .peek(executor -> {
+                    EventPriority priority = getDynamicEventPriority(method);
+                    boolean ignoreCancelled = isIgnoreIfCancelled(method);
+                    Bukkit.getPluginManager().registerEvent(eventClass, listener, priority, executor, plugin, ignoreCancelled);
+                    Logging.finest("Registered dynamic event: %s, priority: %s, ignore if cancelled: %s",
+                            eventClass.getName(), priority, ignoreCancelled);
+                });
     }
 
     private Class<? extends Event> getEventClass(Method method) {
@@ -129,13 +133,12 @@ public final class DynamicListenerRegistration {
     }
 
     private Class<? extends Event> getEventClassFromString(String className) {
-        Class<?> annotatedClass = ReflectHelper.getClass(className);
-        if (annotatedClass == null || !Event.class.isAssignableFrom(annotatedClass)) {
-            // Usually means the server software used did not implement the event
-            Logging.fine("Event class does not exist: %s", className);
-            return null;
-        }
-        return annotatedClass.asSubclass(Event.class);
+        return ReflectHelper.tryGetClass(className)
+                .onFailure(throwable -> Logging.fine("Failed to find event class: %s", className))
+                .filter(Event.class::isAssignableFrom)
+                .onFailure(throwable -> Logging.warning("Class is not an Event: %s", className))
+                .map(clazz -> (Class<? extends Event>) clazz.asSubclass(Event.class))
+                .getOrNull();
     }
 
     private EventPriority getDynamicEventPriority(Method method) {

src/main/java/org/mvplugins/multiverse/core/event/MVDumpsDebugInfoEvent.java

@@ -7,6 +7,7 @@ import java.io.FileReader;
 import java.io.IOException;
 import java.util.Collections;
 import java.util.HashMap;
+import java.util.LinkedHashMap;
 import java.util.Map;
 
 import com.dumptruckman.minecraft.util.Logging;
@@ -24,7 +25,7 @@ public final class MVDumpsDebugInfoEvent extends Event {
 
     public MVDumpsDebugInfoEvent() {
         debugInfoBuilder = new StringBuilder();
-        detailedDebugInfo = new HashMap<>();
+        detailedDebugInfo = new LinkedHashMap<>();
     }
 
     private static final HandlerList HANDLERS = new HandlerList();

src/main/java/org/mvplugins/multiverse/core/event/world/MVWorldClonedEvent.java

@@ -1,8 +1,11 @@
 package org.mvplugins.multiverse.core.event.world;
 
 import org.bukkit.event.HandlerList;
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 import org.mvplugins.multiverse.core.world.LoadedMultiverseWorld;
+import org.mvplugins.multiverse.core.world.MultiverseWorld;
 
 /**
  * Called when a world has been successfully cloned.
@@ -10,14 +13,24 @@ import org.mvplugins.multiverse.core.world.LoadedMultiverseWorld;
 public final class MVWorldClonedEvent extends MultiverseWorldEvent<LoadedMultiverseWorld> {
     private static final HandlerList HANDLERS = new HandlerList();
 
-    private final LoadedMultiverseWorld fromWorld;
+    private final MultiverseWorld fromWorld;
 
-    public MVWorldClonedEvent(LoadedMultiverseWorld world, LoadedMultiverseWorld fromWorld) {
+    public MVWorldClonedEvent(LoadedMultiverseWorld world, MultiverseWorld fromWorld) {
         super(world);
         this.fromWorld = fromWorld;
     }
 
-    public LoadedMultiverseWorld getFromWorld() {
+    /**
+     * @deprecated Cloning can be done from unloaded worlds as well. Use {@link #getSourceWorld()} instead.
+     */
+    @Deprecated(forRemoval = true, since = "5.6")
+    @ApiStatus.ScheduledForRemoval(inVersion = "6.0")
+    public @Nullable LoadedMultiverseWorld getFromWorld() {
+        return fromWorld.asLoadedWorld().getOrNull();
+    }
+
+    @ApiStatus.AvailableSince("5.6")
+    public @NotNull MultiverseWorld getSourceWorld() {
         return fromWorld;
     }
 
@@ -37,5 +50,4 @@ public final class MVWorldClonedEvent extends MultiverseWorldEvent<LoadedMultive
     public static HandlerList getHandlerList() {
         return HANDLERS;
     }
-
 }

src/main/java/org/mvplugins/multiverse/core/exceptions/command/MVInvalidCommandArgument.java

@@ -1,6 +1,8 @@
 package org.mvplugins.multiverse.core.exceptions.command;
 
 import co.aikar.commands.InvalidCommandArgument;
+import org.jetbrains.annotations.ApiStatus;
+import org.mvplugins.multiverse.core.locale.message.LocalizableMessage;
 import org.mvplugins.multiverse.core.locale.message.LocalizedMessage;
 import org.mvplugins.multiverse.core.locale.message.Message;
 
@@ -9,6 +11,18 @@ import org.mvplugins.multiverse.core.locale.message.Message;
  */
 public class MVInvalidCommandArgument extends InvalidCommandArgument {
 
+    @ApiStatus.AvailableSince("5.7")
+    public static MVInvalidCommandArgument causeBy(Throwable throwable) {
+        return causeBy(throwable, true);
+    }
+
+    @ApiStatus.AvailableSince("5.7")
+    public static MVInvalidCommandArgument causeBy(Throwable throwable, boolean showSyntax) {
+        return (throwable instanceof LocalizableMessage localizableMessage)
+                ? of(localizableMessage.getLocalizableMessage(), showSyntax)
+                : new MVInvalidCommandArgument(throwable.getLocalizedMessage(), showSyntax);
+    }
+
     public static MVInvalidCommandArgument of(Message message) {
         return of(message, true);
     }
@@ -19,6 +33,10 @@ public class MVInvalidCommandArgument extends InvalidCommandArgument {
                 : new MVInvalidCommandArgument(message, showSyntax);
     }
 
+    private MVInvalidCommandArgument(String message, boolean showSyntax) {
+        super(message, showSyntax);
+    }
+
     private MVInvalidCommandArgument(Message message, boolean showSyntax) {
         super(message.formatted(), showSyntax);
     }

src/main/java/org/mvplugins/multiverse/core/listeners/MVEntityListener.java

@@ -7,6 +7,7 @@
 
 package org.mvplugins.multiverse.core.listeners;
 
+import com.destroystokyo.paper.event.entity.PreCreatureSpawnEvent;
 import com.dumptruckman.minecraft.util.Logging;
 import jakarta.inject.Inject;
 import org.bukkit.entity.LivingEntity;
@@ -21,6 +22,8 @@ import org.bukkit.event.entity.FoodLevelChangeEvent;
 import org.jetbrains.annotations.NotNull;
 import org.jvnet.hk2.annotations.Service;
 
+import org.mvplugins.multiverse.core.dynamiclistener.EventRunnable;
+import org.mvplugins.multiverse.core.dynamiclistener.annotations.EventClass;
 import org.mvplugins.multiverse.core.dynamiclistener.annotations.EventMethod;
 import org.mvplugins.multiverse.core.world.WorldManager;
 
@@ -77,6 +80,37 @@ final class MVEntityListener implements CoreListener {
                 });
     }
 
+    /**
+     * Fired before other spawn checks is done, helps in performance by cancelling early and preventing unnecessary
+     * checks for spawn reasons that are not allowed in the world.
+     *
+     * @return Event wrapper
+     */
+    @EventClass("com.destroystokyo.paper.event.entity.PreCreatureSpawnEvent")
+    EventRunnable<?> preCreatureSpawn() {
+        return new EventRunnable<PreCreatureSpawnEvent>() {
+            @Override
+            public void onEvent(PreCreatureSpawnEvent event) {
+                // Always allow custom command and plugins to spawn creatures
+                if (event.getReason() == SpawnReason.CUSTOM
+                        || event.getReason() == SpawnReason.COMMAND
+                        || event.getReason() == SpawnReason.BREEDING
+                        || event.getReason() == SpawnReason.SPAWNER_EGG) {
+                    return;
+                }
+
+                worldManager.getLoadedWorld(event.getSpawnLocation().getWorld())
+                        .peek(world -> {
+                            if (!world.getEntitySpawnConfig().shouldAllowSpawn(event.getType())) {
+                                Logging.finest("Cancelling Pre Creature Spawn Event for: " + event.getType());
+                                event.setCancelled(true);
+                                event.setShouldAbortSpawn(true);
+                            }
+                        });
+            }
+        };
+    }
+
     /**
      * Handle Spawn Category settings.
      *

src/main/java/org/mvplugins/multiverse/core/listeners/MVPlayerListener.java

@@ -7,9 +7,7 @@
 
 package org.mvplugins.multiverse.core.listeners;
 
-import java.util.Map;
 import java.util.Objects;
-import java.util.concurrent.ConcurrentHashMap;
 
 import com.dumptruckman.minecraft.util.Logging;
 import io.vavr.control.Option;
@@ -38,6 +36,7 @@ import org.mvplugins.multiverse.core.destination.DestinationsProvider;
 import org.mvplugins.multiverse.core.dynamiclistener.annotations.DefaultEventPriority;
 import org.mvplugins.multiverse.core.dynamiclistener.annotations.EventMethod;
 import org.mvplugins.multiverse.core.dynamiclistener.annotations.EventPriorityKey;
+import org.mvplugins.multiverse.core.dynamiclistener.annotations.IgnoreIfCancelled;
 import org.mvplugins.multiverse.core.economy.MVEconomist;
 import org.mvplugins.multiverse.core.event.MVRespawnEvent;
 import org.mvplugins.multiverse.core.locale.PluginLocales;
@@ -245,7 +244,7 @@ final class MVPlayerListener implements CoreListener {
     }
 
     private void teleportToDestinationOnJoin(Player player, DestinationInstance<?, ?> destination) {
-        asyncSafetyTeleporter.to(destination).teleportSingle(player)
+        asyncSafetyTeleporter.to(destination).passengerMode(config.getPassengerMode()).teleportSingle(player)
                 .onSuccess(result -> Logging.fine("Player %s has been teleported on join",
                         player.getName()))
                 .onFailure(failure -> Logging.warning("Failed to teleport player %s on join: %s",
@@ -257,9 +256,9 @@ final class MVPlayerListener implements CoreListener {
      * @param event The Event that was fired.
      */
     @EventMethod
-    @DefaultEventPriority(EventPriority.MONITOR)
+    @EventPriorityKey("mvcore-player-changed-world")
+    @DefaultEventPriority(EventPriority.NORMAL)
     void playerChangedWorld(PlayerChangedWorldEvent event) {
-        // Permissions now determine whether or not to handle a gamemode.
         this.handleGameModeAndFlight(event.getPlayer(), event.getPlayer().getWorld());
     }
 
@@ -271,12 +270,28 @@ final class MVPlayerListener implements CoreListener {
     @EventPriorityKey("mvcore-player-teleport")
     @DefaultEventPriority(EventPriority.HIGHEST)
     void playerTeleport(PlayerTeleportEvent event) {
-        Logging.finer("Got teleport event for player '"
-                + event.getPlayer().getName() + "' with cause '" + event.getCause() + "'");
+        Player teleportee = event.getPlayer();
+
         if (event.isCancelled()) {
+            Logging.finer("Teleport event for player '" + teleportee.getName() + "' was already cancelled.");
             return;
         }
-        Player teleportee = event.getPlayer();
+
+        Logging.finer("Got teleport event for player '"
+                + teleportee.getName() + "' with cause '" + event.getCause() + "'");
+
+        Location fromLocation = event.getFrom();
+        if (fromLocation == null || fromLocation.getWorld() == null) { // should never be null, but just in case
+            Logging.finer("Teleport event for player '" + teleportee.getName() + "' has null from-location or world.");
+            return;
+        }
+
+        Location toLocation = event.getTo();
+        if (toLocation == null || toLocation.getWorld() == null) { // may be null on spigot
+            Logging.finer("Teleport event for player '" + teleportee.getName() + "' has null to-location or world.");
+            return;
+        }
+
         Option<String> teleporterName = teleportQueue.popFromQueue(teleportee.getName());
         CommandSender teleporter = teleporterName.map(name -> {
             if (name.equalsIgnoreCase("CONSOLE")) {
@@ -297,17 +312,17 @@ final class MVPlayerListener implements CoreListener {
         }
 
         Logging.finer("Teleporter %s is teleporting %s from %s to %s", teleporter.getName(), teleportee.getName(),
-                event.getFrom(), event.getTo());
+                fromLocation, toLocation);
 
-        MultiverseWorld fromWorld = getWorldManager().getLoadedWorld(event.getFrom().getWorld()).getOrNull();
-        LoadedMultiverseWorld toWorld = getWorldManager().getLoadedWorld(event.getTo().getWorld()).getOrNull();
+        MultiverseWorld fromWorld = getWorldManager().getLoadedWorld(fromLocation.getWorld()).getOrNull();
+        LoadedMultiverseWorld toWorld = getWorldManager().getLoadedWorld(toLocation.getWorld()).getOrNull();
         if (toWorld == null) {
             Logging.fine("Player '" + teleportee.getName() + "' is teleporting to world '"
-                    + event.getTo().getWorld().getName() + "' which is not managed by Multiverse-Core.  No further "
+                    + toLocation.getWorld().getName() + "' which is not managed by Multiverse-Core.  No further "
                     + "actions will be taken by Multiverse-Core.");
             return;
         }
-        if (event.getFrom().getWorld().equals(event.getTo().getWorld())) {
+        if (fromLocation.getWorld().equals(toLocation.getWorld())) {
             // The player is Teleporting to the same world.
             Logging.finer("Player '" + teleportee.getName() + "' is teleporting to the same world.");
             this.stateSuccess(teleportee.getName(), toWorld.getName());
@@ -341,20 +356,19 @@ final class MVPlayerListener implements CoreListener {
      */
     @EventMethod
     @DefaultEventPriority(EventPriority.LOWEST)
+    @IgnoreIfCancelled
     void playerPortalCheck(PlayerPortalEvent event) {
-        if (event.isCancelled()) {
-            return;
-        }
-        if (event.getFrom().getWorld() == null) {
+        Location fromLocation = event.getFrom();
+        if (fromLocation == null || fromLocation.getWorld() == null) {
             Logging.warning("PlayerPortalEvent's from world is null!");
             return;
         }
-        if (event.getFrom().getWorld().getBlockAt(event.getFrom()).getType() == Material.NETHER_PORTAL) {
+        if (fromLocation.getWorld().getBlockAt(fromLocation).getType() == Material.NETHER_PORTAL) {
             return;
         }
 
         // Player was actually outside of the portal, adjust the from location
-        Location newLocation = blockSafety.findPortalBlockNextTo(event.getFrom());
+        Location newLocation = blockSafety.findPortalBlockNextTo(fromLocation);
         if (newLocation != null) {
             event.setFrom(newLocation);
         }
@@ -367,28 +381,33 @@ final class MVPlayerListener implements CoreListener {
     @EventMethod
     @EventPriorityKey("mvcore-player-portal")
     @DefaultEventPriority(EventPriority.HIGH)
+    @IgnoreIfCancelled
     void playerPortal(PlayerPortalEvent event) {
-        if (event.isCancelled()) {
+        Location fromLocation = event.getFrom();
+        if (fromLocation == null || fromLocation.getWorld() == null) { // should never be null, but just in case
+            Logging.finer("PlayerPortalEvent's from world is null!");
             return;
         }
-        if (event.getTo() == null || event.getTo().getWorld() == null) {
+
+        Location toLocation = event.getTo();
+        if (toLocation == null || toLocation.getWorld() == null) { // may be null on spigot
             Logging.finer("PlayerPortalEvent's to world is null!");
             return;
         }
         if (config.isUsingCustomPortalSearch()) {
             event.setSearchRadius(config.getCustomPortalSearchRadius());
         }
-        if (Objects.equals(event.getFrom().getWorld(), event.getTo().getWorld())) {
+        if (Objects.equals(fromLocation.getWorld(), toLocation.getWorld())) {
             // The player is Portaling to the same world.
             Logging.finer("Player '" + event.getPlayer().getName() + "' is portaling to the same world.");
             return;
         }
 
-        MultiverseWorld fromWorld = getWorldManager().getLoadedWorld(event.getFrom().getWorld()).getOrNull();
-        LoadedMultiverseWorld toWorld = getWorldManager().getLoadedWorld(event.getTo().getWorld()).getOrNull();
+        MultiverseWorld fromWorld = getWorldManager().getLoadedWorld(fromLocation.getWorld()).getOrNull();
+        LoadedMultiverseWorld toWorld = getWorldManager().getLoadedWorld(toLocation.getWorld()).getOrNull();
         if (toWorld == null) {
             Logging.fine("Player '" + event.getPlayer().getName() + "' is portaling to world '"
-                    + event.getTo().getWorld().getName() + "' which is not managed by Multiverse-Core.  No further "
+                    + toLocation.getWorld().getName() + "' which is not managed by Multiverse-Core.  No further "
                     + "actions will be taken by Multiverse-Core.");
             return;
         }
@@ -402,21 +421,31 @@ final class MVPlayerListener implements CoreListener {
     }
 
     /**
-     * Handles the gamemode for the specified {@link Player}.
+     * Handles the gamemode for the specified {@link Player}. Delays the enforcement if configured to do so
+     * to ensure multiverse has final say over other plugins changing gamemodes.
      *
      * @param player The {@link Player}.
      * @param world  The {@link World} the player is supposed to be in.
      */
     private void handleGameModeAndFlight(final Player player, World world) {
-        // We perform this task one tick later to MAKE SURE that the player actually reaches the
-        // destination world, otherwise we'd be changing the player mode if they havent moved anywhere.
-        this.server.getScheduler().runTaskLater(this.plugin, () -> {
-            if (!player.isOnline() || !player.getWorld().equals(world)) {
-                return;
-            }
-            Logging.finer("Handling gamemode and flight for player %s in world '%s'", player.getName(), world.getName());
-            enforcementHandler.handleFlightEnforcement(player);
-            enforcementHandler.handleGameModeEnforcement(player);
-        }, 1L);
+        if (config.getGamemodeAndFlightEnforceDelay() <= 0) {
+            doGameModeAndFlightEnforcement(player, world);
+            return;
+        }
+        server.getScheduler().runTaskLater(
+                this.plugin,
+                () -> doGameModeAndFlightEnforcement(player, world),
+                config.getGamemodeAndFlightEnforceDelay()
+        );
+    }
+
+    private void doGameModeAndFlightEnforcement(Player player, World world) {
+        if (!player.isOnline() || !player.getWorld().equals(world)) {
+            Logging.finer("Player %s is no longer online or not in the expected world '%s'", player.getName(), world.getName());
+            return;
+        }
+        Logging.finer("Handling gamemode and flight for player %s in world '%s'", player.getName(), world.getName());
+        enforcementHandler.handleFlightEnforcement(player);
+        enforcementHandler.handleGameModeEnforcement(player);
     }
 }

src/main/java/org/mvplugins/multiverse/core/listeners/MVPortalListener.java

@@ -18,9 +18,11 @@ import org.bukkit.event.player.PlayerInteractEvent;
 import org.bukkit.event.world.PortalCreateEvent;
 import org.jetbrains.annotations.NotNull;
 import org.jvnet.hk2.annotations.Service;
+import org.mvplugins.multiverse.core.command.MVCommandManager;
 import org.mvplugins.multiverse.core.config.CoreConfig;
 import org.mvplugins.multiverse.core.dynamiclistener.annotations.EventMethod;
 import org.mvplugins.multiverse.core.dynamiclistener.annotations.IgnoreIfCancelled;
+import org.mvplugins.multiverse.core.locale.MVCorei18n;
 import org.mvplugins.multiverse.core.world.WorldManager;
 
 import static org.bukkit.PortalType.CUSTOM;
@@ -33,11 +35,15 @@ final class MVPortalListener implements CoreListener {
 
     private final CoreConfig config;
     private final WorldManager worldManager;
+    private final MVCommandManager commandManager;
 
     @Inject
-    MVPortalListener(@NotNull CoreConfig config, @NotNull WorldManager worldManager) {
+    MVPortalListener(@NotNull CoreConfig config,
+                     @NotNull WorldManager worldManager,
+                     @NotNull MVCommandManager commandManager) {
         this.config = config;
         this.worldManager = worldManager;
+        this.commandManager = commandManager;
     }
 
     /**
@@ -59,6 +65,7 @@ final class MVPortalListener implements CoreListener {
             if (!world.getPortalForm().isPortalAllowed(targetType)) {
                 Logging.fine("Cancelling creation of %s portal because portalForm disallows.", targetType);
                 event.setCancelled(true);
+                commandManager.getCommandIssuer(event.getEntity()).sendError(MVCorei18n.PORTALFORM_DISABLED_NETHER);
             }
         }).onEmpty(() ->
                 Logging.fine("World '%s' is not managed by Multiverse! Ignoring at PortalCreateEvent.",
@@ -101,6 +108,7 @@ final class MVPortalListener implements CoreListener {
             if (!world.getPortalForm().isPortalAllowed(PortalType.ENDER)) {
                 Logging.fine("Cancelling creation of ENDER portal because portalForm disallows.");
                 event.setCancelled(true);
+                commandManager.getCommandIssuer(event.getPlayer()).sendError(MVCorei18n.PORTALFORM_DISABLED_END);
             }
         }).onEmpty(() ->
                 Logging.fine("World '%s' is not managed by Multiverse! Ignoring at PlayerInteractEvent.",

src/main/java/org/mvplugins/multiverse/core/locale/MVCorei18n.java

@@ -91,6 +91,7 @@ public enum MVCorei18n implements MessageKeyProvider {
 
     // /mv dumps
     DUMPS_DESCRIPTION,
+    DUMPS_STARTING,
     DUMPS_URL_LIST,
 
     // /mv gamerule set
@@ -146,6 +147,19 @@ public enum MVCorei18n implements MessageKeyProvider {
     LOAD_LOADING,
     LOAD_SUCCESS,
 
+    // /mv meta info
+    META_INFO_DESCRIPTION,
+    META_INFO_WORLD,
+    META_INFO_HEADER,
+    META_INFO_NOCONTENT,
+
+    // /mv meta modify
+    META_MODIFY_SET_SUCCESS,
+    META_MODIFY_SET_FAILURE,
+    META_MODIFY_REMOVE_SUCCESS,
+    META_MODIFY_REMOVE_FAILURE,
+    META_MODIFY_INVALIDACTION,
+
     // /mv modify
     MODIFY_DESCRIPTION,
     MODIFY_WORLD_DESCRIPTION,
@@ -250,6 +264,8 @@ public enum MVCorei18n implements MessageKeyProvider {
     WORLDBORDER_WARNINGTIME_NOTHINGCHANGED,
     WORLDBORDER_WARNINGTIME_SUCCESS,
 
+    WORLDBORDER_ROUNDOFF_WARNING,
+
     // commands error
     COMMANDS_ERROR_PLAYERSONLY,
     COMMANDS_ERROR_MULTIVERSEWORLDONLY,
@@ -278,6 +294,10 @@ public enum MVCorei18n implements MessageKeyProvider {
     DESTINATION_SHARED_FAILUREREASON_WORLDNOTFOUND,
     DESTINATION_PARSE_FAILUREREASON_INVALIDDESTINATIONID,
 
+    // portal form disabled
+    PORTALFORM_DISABLED_END,
+    PORTALFORM_DISABLED_NETHER,
+
     // teleport failure reason
     TELEPORTFAILUREREASON_NULL_DESTINATION,
     TELEPORTFAILUREREASON_NULL_LOCATION,
@@ -292,6 +312,7 @@ public enum MVCorei18n implements MessageKeyProvider {
     CLONEWORLD_WORLDEXISTFOLDER,
     CLONEWORLD_WORLDEXISTUNLOADED,
     CLONEWORLD_WORLDEXISTLOADED,
+    CLONEWORLD_FROMWORLDFOLDERINVALID,
     CLONEWORLD_COPYFAILED,
 
     CREATEWORLD_INVALIDWORLDNAME,
@@ -309,12 +330,14 @@ public enum MVCorei18n implements MessageKeyProvider {
     IMPORTWORLD_WORLDEXISTLOADED,
     IMPORTWORLD_WORLDFOLDERINVALID,
     IMPORTWORLD_BUKKITENVIRONMENTMISMATCH,
+    IMPORTWORLD_BUKKITNAMESPACEDKEYMISMATCH,
 
     LOADWORLD_WORLDALREADYLOADING,
     LOADWORLD_WORLDNONEXISTENT,
     LOADWORLD_WORLDEXISTFOLDER,
     LOADWORLD_WORLDEXISTLOADED,
     LOADWORLD_BUKKITENVIRONMENTMISMATCH,
+    LOADWORLD_BUKKITNAMESPACEDKEYMISMATCH,
 
     REMOVEWORLD_WORLDNONEXISTENT,
 
@@ -351,6 +374,12 @@ public enum MVCorei18n implements MessageKeyProvider {
     EXCEPTION_POSITIONPARSE_INVALIDCOORDINATES,
     EXCEPTION_POSITIONPARSE_INVALIDNUMBER,
 
+    // world key parse failures
+    WORLDKEYPARSE_EMPTY,
+    WORLDKEYPARSE_INVALIDWORLDNAME,
+    WORLDKEYPARSE_INVALIDNAMESPACEDKEY,
+    WORLDKEYPARSE_NAMESPACEDKEYUNSUPPORTED,
+
     // generic
     GENERIC_SUCCESS,
     GENERIC_FAILURE,

src/main/java/org/mvplugins/multiverse/core/locale/message/MessageReplacement.java

@@ -1,6 +1,7 @@
 package org.mvplugins.multiverse.core.locale.message;
 
 import io.vavr.control.Either;
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.Contract;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
@@ -107,6 +108,7 @@ public final class MessageReplacement {
         GAMERULE(replace("{gamerule}")),
         LOCATION(replace("{location}")),
         NAME(replace("{name}")),
+        NAMESPACE(replace("{namespace}")),
         PLAYER(replace("{player}")),
         REASON(replace("{reason}")),
         VALUE(replace("{value}")),

src/main/java/org/mvplugins/multiverse/core/module/MultiverseModule.java

@@ -147,9 +147,10 @@ public abstract class MultiverseModule extends JavaPlugin {
         Try.of(() -> commandManagerProvider.get())
                 .mapTry(MVCommandManager::getLocales)
                 .andThen(pluginLocales -> {
-                    pluginLocales.addFileResClassLoader(this);
                     pluginLocales.addBundleClassLoader(this.getClassLoader());
+                    pluginLocales.addFileResClassLoader(this);
                     pluginLocales.addMessageBundles(this.getName().toLowerCase(Locale.ENGLISH));
+                    pluginLocales.loadLanguages();
                 })
                 .onFailure(e -> {
                     Logging.severe("Failed to register locales");

src/main/java/org/mvplugins/multiverse/core/teleportation/BlockSafety.java

@@ -132,6 +132,10 @@ public final class BlockSafety {
      */
     public boolean canSpawnAtBlockSafely(@NotNull Block block) {
         Logging.finest("Checking spawn safety for location: %s, %s, %s", block.getX(), block.getY(), block.getZ());
+        if (!block.getWorld().getWorldBorder().isInside(block.getLocation())) {
+            Logging.finest("Location is outside world border.");
+            return false;
+        }
         if (isUnsafeSpawnBody(block)) {
             // Player body will be stuck in solid
             Logging.finest("Unsafe location for player's body: " + block);

src/main/java/org/mvplugins/multiverse/core/utils/CaseInsensitiveStringMap.java

@@ -0,0 +1,92 @@
+package org.mvplugins.multiverse.core.utils;
+
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.Locale;
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * A map with case-insensitive String keys. All keys are stored in lower-case form.
+ *
+ * @param <T> the type of mapped values
+ *
+ * @since 5.5
+ */
+@ApiStatus.AvailableSince("5.5")
+public class CaseInsensitiveStringMap<T> implements Map<String, T> {
+
+    private final Map<String, T> map;
+
+    public CaseInsensitiveStringMap() {
+        map = new HashMap<>();
+    }
+
+    @Override
+    public int size() {
+        return map.size();
+    }
+
+    @Override
+    public boolean isEmpty() {
+        return map.isEmpty();
+    }
+
+    @Override
+    public boolean containsKey(Object key) {
+        return map.containsKey(normalizeKey(key));
+    }
+
+    @Override
+    public boolean containsValue(Object value) {
+        return map.containsValue(value);
+    }
+
+    @Override
+    public T get(Object key) {
+        return map.get(normalizeKey(key));
+    }
+
+    @Override
+    public @Nullable T put(String key, T value) {
+        return map.put(normalizeKey(key), value);
+    }
+
+    @Override
+    public T remove(Object key) {
+        return map.remove(normalizeKey(key));
+    }
+
+    @Override
+    public void putAll(@NotNull Map<? extends String, ? extends T> m) {
+        m.forEach((key, value) -> map.put(normalizeKey(key), value));
+    }
+
+    @Override
+    public void clear() {
+        map.clear();
+    }
+
+    @Override
+    public @NotNull Set<String> keySet() {
+        return map.keySet();
+    }
+
+    @Override
+    public @NotNull Collection<T> values() {
+        return map.values();
+    }
+
+    @Override
+    public @NotNull Set<Entry<String, T>> entrySet() {
+        return map.entrySet();
+    }
+
+    private String normalizeKey(Object key) {
+        return String.valueOf(key).toLowerCase(Locale.ROOT);
+    }
+}

src/main/java/org/mvplugins/multiverse/core/utils/FileUtils.java

@@ -18,6 +18,7 @@ import java.util.Collection;
 import java.util.Collections;
 import java.util.Comparator;
 import java.util.List;
+import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
 import com.dumptruckman.minecraft.util.Logging;
@@ -210,28 +211,31 @@ public final class FileUtils {
 
         private final Path sourceDir;
         private final Path targetDir;
-        private final List<String> excludeFiles;
+        private final List<Path> excludeFiles;
 
         private CopyDirFileVisitor(@NotNull Path sourceDir, @NotNull Path targetDir, @NotNull List<String> excludeFiles) {
             this.sourceDir = sourceDir;
             this.targetDir = targetDir;
-            this.excludeFiles = excludeFiles;
+            this.excludeFiles = excludeFiles.stream()
+                    .map(sourceDir::resolve)
+                    .toList();
+            Logging.finest(this.excludeFiles.stream().map(Path::toString).collect(Collectors.joining(", ", "Exclude files: [", "]")));
         }
 
         @Override
-        public @NotNull FileVisitResult preVisitDirectory(Path dir, @NotNull BasicFileAttributes attrs) throws IOException {
+        public @NotNull FileVisitResult preVisitDirectory(@NotNull Path dir, @NotNull BasicFileAttributes attrs) throws IOException {
             Path newDir = targetDir.resolve(sourceDir.relativize(dir));
             if (!Files.isDirectory(newDir)) {
-                Files.createDirectory(newDir);
+                Files.createDirectories(newDir);
             }
             return FileVisitResult.CONTINUE;
         }
 
         @Override
-        public @NotNull FileVisitResult visitFile(Path file, @NotNull BasicFileAttributes attrs) throws IOException {
+        public @NotNull FileVisitResult visitFile(@NotNull Path file, @NotNull BasicFileAttributes attrs) throws IOException {
             // Pass files that are set to ignore
-            if (excludeFiles.contains(file.getFileName().toString())) {
-                Logging.finest("Ignoring file: " + file.getFileName());
+            if (excludeFiles.contains(file)) {
+                Logging.finest("Ignoring file: " + file);
                 return FileVisitResult.CONTINUE;
             }
             // Copy the files

src/main/java/org/mvplugins/multiverse/core/utils/MinecraftTimeFormatter.java

@@ -1,8 +1,8 @@
 package org.mvplugins.multiverse.core.utils;
 
 import io.vavr.control.Try;
-import org.checkerframework.checker.nullness.qual.Nullable;
 import org.jetbrains.annotations.ApiStatus;
+import org.mvplugins.multiverse.core.utils.tick.TickDuration;
 
 import java.time.LocalTime;
 import java.time.format.DateTimeFormatter;
@@ -15,10 +15,6 @@ import java.time.format.DateTimeFormatter;
 @ApiStatus.AvailableSince("5.1")
 public final class MinecraftTimeFormatter {
 
-    private static final double TIME_MULTIPLIER = 3.6;
-    private static final long DAY_SECONDS = 24 * 60 * 60;
-    private static final long START_OFFSET = 6 * 60 * 60;
-
     /**
      * Formats Minecraft time to 12-hour format.
      *
@@ -48,19 +44,14 @@ public final class MinecraftTimeFormatter {
      * See <a href="https://docs.oracle.com/javase/8/docs/api/java/time/format/DateTimeFormatter.html">DateTimeFormatter documentation</a>
      * for available patterns.
      *
-     * @param time   The Minecraft time to format.
-     * @param format The format string for the time.
+     * @param ticks     The Minecraft time to format.
+     * @param format    The format string for the time.
      *
      * @since 5.1
      */
     @ApiStatus.AvailableSince("5.1")
-    public static String formatTime(long time, String format) {
-        // Convert Minecraft time to real-world time
-        long realTime = (long) ((time * TIME_MULTIPLIER) + START_OFFSET) % DAY_SECONDS;  // Minecraft ticks to seconds
-
-        // Convert seconds to LocalTime
-        LocalTime localTime = LocalTime.ofSecondOfDay(realTime);
-
+    public static String formatTime(long ticks, String format) {
+        LocalTime localTime = TickDuration.ofTicks(ticks).toLocalTime();
         return Try.of(() -> DateTimeFormatter.ofPattern(format))
                 .map(localTime::format)
                 .getOrElse("invalid time format: " + format);

src/main/java/org/mvplugins/multiverse/core/utils/ReflectHelper.java

@@ -3,6 +3,8 @@ package org.mvplugins.multiverse.core.utils;
 import java.lang.reflect.Field;
 import java.lang.reflect.Method;
 
+import io.vavr.control.Try;
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
@@ -15,8 +17,178 @@ public final class ReflectHelper {
      * Try to get the {@link Class} based on its classpath.
      *
      * @param classPath The target classpath.
-     * @return A {@link Class} if found, else null.
+     * @return A {@link Try} containing the {@link Class} if found, else a failure.
+     *
+     * @since 5.7
      */
+    @ApiStatus.AvailableSince("5.7")
+    @NotNull
+    public static Try<Class<?>> tryGetClass(@NotNull String classPath) {
+        return Try.of(() -> Class.forName(classPath));
+    }
+
+    /**
+     * Check if the {@link Class} for a give classpath is present/valid.
+     *
+     * @param classPath Target classpath.
+     * @return True if class path is a valid class, else false.
+     */
+    public static boolean hasClass(String classPath) {
+        return tryGetClass(classPath).isSuccess();
+    }
+
+    /**
+     * Try to get a {@link Method} from a given class.
+     *
+     * @param clazz             The class to search the method on.
+     * @param methodName        Name of the method to get.
+     * @param parameterTypes    Parameters present for that method.
+     * @param <C>               The class type.
+     * @return A {@link Try} containing the {@link Method} if found, else a failure.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    @NotNull
+    public static <C> Try<Method> tryGetMethod(@NotNull Class<C> clazz, @NotNull String methodName, Class<?>... parameterTypes) {
+        return Try.of(() -> clazz.getMethod(methodName, parameterTypes))
+                .orElse(Try.of(() -> {
+                    Method method = clazz.getDeclaredMethod(methodName, parameterTypes);
+                    method.setAccessible(true);
+                    return method;
+                }));
+    }
+
+    /**
+     * Check if a {@link Method} exists on a given class.
+     *
+     * @param clazz             The class to search the method on.
+     * @param methodName        Name of the method to check.
+     * @param parameterTypes    Parameters present for that method.
+     * @return True if method exists, else false.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static boolean hasMethod(@NotNull Class<?> clazz, @NotNull String methodName, Class<?>... parameterTypes) {
+        return tryGetMethod(clazz, methodName, parameterTypes).isSuccess();
+    }
+
+    /**
+     * Try to invoke a {@link Method} on a class instance.
+     *
+     * @param classInstance Instance of the class responsible for the method.
+     * @param method        The method to invoke.
+     * @param parameters    Parameters needed when invoking the method.
+     * @param <C>           The class type.
+     * @param <R>           The return type of the method.
+     * @return A {@link Try} containing the return value of the method if found, else a failure.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    @NotNull
+    @SuppressWarnings("unchecked")
+    public static <C, R> Try<R> tryInvokeMethod(@NotNull C classInstance, @NotNull Method method, Object...parameters) {
+        return Try.of(() -> (R) method.invoke(classInstance, parameters));
+    }
+
+    /**
+     * Try to invoke a static {@link Method}.
+     *
+     * @param method        The static method to invoke.
+     * @param parameters    Parameters needed when invoking the method.
+     * @param <R>           The return type of the method.
+     * @return A {@link Try} containing the return value of the method if found, else a failure.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    @NotNull
+    @SuppressWarnings("unchecked")
+    public static <R> Try<R> tryInvokeStaticMethod(@NotNull Method method, Object...parameters) {
+        return Try.of(() -> (R) method.invoke(null, parameters));
+    }
+
+    /**
+     * Try to get a {@link Field} from a given class.
+     *
+     * @param clazz     The class to search the field on.
+     * @param fieldName Name of the field to get.
+     * @param <C>       The class type.
+     * @return A {@link Try} containing the {@link Field} if found, else a failure.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    @NotNull
+    public static <C> Try<Field> tryGetField(@NotNull Class<C> clazz, @NotNull String fieldName) {
+        return Try.of(() -> clazz.getField(fieldName))
+                .orElse(Try.of(() -> {
+                    Field field = clazz.getDeclaredField(fieldName);
+                    field.setAccessible(true);
+                    return field;
+                }));
+    }
+
+    /**
+     * Check if a {@link Field} exists on a given class.
+     *
+     * @param clazz     The class to search the field on.
+     * @param fieldName Name of the field to check.
+     * @return True if field exists, else false.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static boolean hasField(@NotNull Class<?> clazz, @NotNull String fieldName) {
+        return tryGetField(clazz, fieldName).isSuccess();
+    }
+
+    /**
+     * Try to get the value of a {@link Field} from an instance of the class responsible.
+     *
+     * @param classInstance Instance of the class to get the field value from.
+     * @param field         The field to get the value from.
+     * @param fieldType     Type of the field.
+     * @param <C>           The class type.
+     * @param <V>           The field value type.
+     * @return A {@link Try} containing the field value if found, else a failure.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    @NotNull
+    public static <C, V> Try<V> tryGetFieldValue(@NotNull C classInstance, @NotNull Field field, @NotNull Class<V> fieldType) {
+        return Try.of(() -> fieldType.cast(field.get(classInstance)));
+    }
+
+    /**
+     * Try to get the value of a static {@link Field}.
+     *
+     * @param field     The static field to get the value from.
+     * @param fieldType Type of the field.
+     * @param <V>       The field value type.
+     * @return A {@link Try} containing the field value if found, else a failure.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    @NotNull
+    public static <V> Try<V> tryGetStaticFieldValue(@NotNull Field field, @NotNull Class<V> fieldType) {
+        return Try.of(() -> fieldType.cast(field.get(null)));
+    }
+
+    /**
+     * Try to get the {@link Class} based on its classpath.
+     *
+     * @param classPath The target classpath.
+     * @return A {@link Class} if found, else null.
+     *
+     * @deprecated Use {@link #tryGetClass(String)} instead, which returns a {@link Try} that can be used to handle
+     * the failure case more explicitly.
+     */
+    @Deprecated(forRemoval = true, since = "5.7")
     @Nullable
     public static Class<?> getClass(String classPath) {
         try {
@@ -26,16 +198,6 @@ public final class ReflectHelper {
         }
     }
 
-    /**
-     * Check if the {@link Class} for a give classpath is present/valid.
-     *
-     * @param classPath Target classpath.
-     * @return True if class path is a valid class, else false.
-     */
-    public static boolean hasClass(String classPath) {
-        return getClass(classPath) != null;
-    }
-
     /**
      * Try to get a {@link Method} from a given class.
      *
@@ -44,7 +206,11 @@ public final class ReflectHelper {
      * @param parameterTypes    Parameters present for that method.
      * @param <C>               The class type.
      * @return A {@link Method} if found, else null.
+     *
+     * @deprecated Use {@link #tryGetMethod(Class, String, Class[])} instead, which returns a {@link Try} that can be
+     * used to handle the failure case more explicitly.
      */
+    @Deprecated(forRemoval = true, since = "5.7")
     @Nullable
     public static <C> Method getMethod(Class<C> clazz, String methodName, Class<?>... parameterTypes) {
         try {
@@ -64,7 +230,11 @@ public final class ReflectHelper {
      * @param parameterTypes    Parameters present for that method.
      * @param <C>               The class type.
      * @return A {@link Method} if found, else null.
+     *
+     * @deprecated Use {@link #tryGetMethod(Class, String, Class[])} instead, which returns a {@link Try} that can be
+     * used to handle the failure case more explicitly.
      */
+    @Deprecated(forRemoval = true, since = "5.7")
     @Nullable
     public static <C> Method getMethod(C classInstance, String methodName, Class<?>... parameterTypes) {
         return getMethod(classInstance.getClass(), methodName, parameterTypes);
@@ -79,8 +249,13 @@ public final class ReflectHelper {
      * @param <C>           The class type.
      * @param <R>           The return type.
      * @return Return value of the method call if any, else null.
+     *
+     * @deprecated Use {@link #tryInvokeMethod(Object, Method, Object...)} instead, which returns a {@link Try} that can
+     * be used to handle the failure case more explicitly.
      */
+    @Deprecated(forRemoval = true, since = "5.7")
     @Nullable
+    @SuppressWarnings("unchecked")
     public static <C, R> R invokeMethod(C classInstance, Method method, Object...parameters) {
         try {
             return (R) method.invoke(classInstance, parameters);
@@ -96,7 +271,11 @@ public final class ReflectHelper {
      * @param fieldName Name of the field to get.
      * @param <C>       The class type.
      * @return A {@link Field} if found, else null.
+     *
+     * @deprecated Use {@link #tryGetField(Class, String)} instead, which returns a {@link Try} that can be used to
+     * handle the failure case more explicitly.
      */
+    @Deprecated(forRemoval = true, since = "5.7")
     @Nullable
     public static <C> Field getField(Class<C> clazz, String fieldName) {
         try {
@@ -115,7 +294,11 @@ public final class ReflectHelper {
      * @param fieldName     Name of the field to get.
      * @param <C>           The class type.
      * @return A {@link Field} if found, else null.
+     *
+     * @deprecated Use {@link #tryGetField(Class, String)} instead, which returns a {@link Try} that can be used to
+     * handle the failure case more explicitly.
      */
+    @Deprecated(forRemoval = true, since = "5.7")
     @Nullable
     public static <C> Field getField(C classInstance, String fieldName) {
         return getField(classInstance.getClass(), fieldName);
@@ -130,7 +313,11 @@ public final class ReflectHelper {
      * @param <C>           The class type.
      * @param <V>           The field value type.
      * @return The field value if any, else null.
+     *
+     * @deprecated Use {@link #tryGetFieldValue(Object, Field, Class)} instead, which returns a {@link Try} that can be
+     * used to handle the failure case more explicitly.
      */
+    @Deprecated(forRemoval = true, since = "5.7")
     @Nullable
     public static <C, V> V getFieldValue(C classInstance, @Nullable Field field, @NotNull Class<V> fieldType) {
         try {
@@ -153,7 +340,11 @@ public final class ReflectHelper {
      * @param <C>           The class type.
      * @param <V>           The field value type.
      * @return The field value if any, else null.
+     *
+     * @deprecated Use {@link #tryGetField(Class, String)} then map to {@link #tryGetFieldValue(Object, Field, Class)} instead,
+     * which returns a {@link Try} that can be used to handle the failure case more explicitly.
      */
+    @Deprecated(forRemoval = true, since = "5.7")
     @Nullable
     public static <C, V> V getFieldValue(C classInstance, @Nullable String fieldName, @NotNull Class<V> fieldType) {
         return getFieldValue(classInstance, getField(classInstance, fieldName), fieldType);

src/main/java/org/mvplugins/multiverse/core/utils/ServerProperties.java

@@ -3,6 +3,7 @@ package org.mvplugins.multiverse.core.utils;
 import com.dumptruckman.minecraft.util.Logging;
 import io.vavr.control.Option;
 import jakarta.inject.Inject;
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 import org.jvnet.hk2.annotations.Service;
 
@@ -14,6 +15,21 @@ import java.util.Map;
 @Service
 public final class ServerProperties {
 
+    private static ServerProperties instance;
+
+    /**
+     * A very bad static way of obtaining the level name from server.properties of older mc versions that
+     * don't have any way of getting main level name.
+     * <br />
+     * For internal use ONLY!
+     *
+     * @return The level name if it can be obtained, else none.
+     */
+    @ApiStatus.Internal
+    public static Option<String> getStaticLevelName() {
+        return Option.of(instance).flatMap(ServerProperties::getLevelName);
+    }
+
     private final Map<String, String> properties;
     private final FileUtils fileUtils;
 
@@ -22,6 +38,8 @@ public final class ServerProperties {
         this.fileUtils = fileUtils;
         properties = new HashMap<>();
         parseServerPropertiesFile();
+
+        instance = this;
     }
 
     private void parseServerPropertiesFile() {

src/main/java/org/mvplugins/multiverse/core/utils/StringFormatter.java

@@ -2,13 +2,17 @@ package org.mvplugins.multiverse.core.utils;
 
 import com.google.common.base.Strings;
 import com.google.common.collect.Sets;
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.Contract;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
+import org.jetbrains.annotations.Unmodifiable;
 
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.List;
+import java.util.Map;
 import java.util.Set;
 import java.util.stream.Collectors;
 
@@ -30,15 +34,15 @@ public final class StringFormatter {
      * @param list the list of strings to join. If the list is empty, an empty string is returned.
      * @return the concatenated string
      */
-    public static @NotNull String joinAnd(List<String> list) {
+    public static @NotNull String joinAnd(@Nullable List<String> list) {
         return join(list, ", ", " and ");
     }
 
-    public static @NotNull String join(Collection list, String separator) {
+    public static @NotNull String join(@Nullable Collection<?> list, @NotNull String separator) {
         if (list == null || list.isEmpty()) {
             return "";
         }
-        return list.stream().map(String::valueOf).collect(Collectors.joining(separator)).toString();
+        return list.stream().map(String::valueOf).collect(Collectors.joining(separator));
     }
 
     /**
@@ -50,7 +54,7 @@ public final class StringFormatter {
      * @param lastSeparator the separator to use before the last element. For example, " and ".
      * @return the concatenated string
      */
-    public static @NotNull String join(List<String> list, String separator, String lastSeparator) {
+    public static @NotNull String join(@Nullable List<String> list, @NotNull String separator, @NotNull String lastSeparator) {
         if (list == null || list.isEmpty()) {
             return "";
         }
@@ -71,11 +75,30 @@ public final class StringFormatter {
 
     /**
      * Appends a list of suggestions to the end of the input string, separated by commas.
+     *
      * @param input     The current input
      * @param addons    The autocomplete suggestions
      * @return A collection of suggestions with the next suggestion appended
+     *
+     * @deprecated Method name has a spelling error. Use {@link #addOnToCommaSeparated(String, Collection)} instead.
      */
+    @Deprecated(forRemoval = true, since = "5.5")
+    @ApiStatus.ScheduledForRemoval(inVersion = "6.0")
     public static Collection<String> addonToCommaSeperated(@Nullable String input, @NotNull Collection<String> addons) {
+        return addOnToCommaSeparated(input, addons);
+    }
+
+    /**
+     * Appends a list of suggestions to the end of the input string, separated by commas.
+     *
+     * @param input     The current input
+     * @param addons    The autocomplete suggestions
+     * @return A collection of suggestions with the next suggestion appended
+     *
+     * @since 5.5
+     */
+    @ApiStatus.AvailableSince("5.5")
+    public static Collection<String> addOnToCommaSeparated(@Nullable String input, @NotNull Collection<String> addons) {
         if (Strings.isNullOrEmpty(input)) {
             return addons;
         }
@@ -94,7 +117,7 @@ public final class StringFormatter {
      * @param args  The args to parse
      * @return The parsed args
      */
-    public static Collection<String> parseQuotesInArgs(String[] args) {
+    public static @NotNull Collection<String> parseQuotesInArgs(@NotNull String[] args) {
         List<String> result = new ArrayList<>(args.length);
         StringBuilder current = new StringBuilder();
         boolean inQuotes = false;
@@ -139,7 +162,28 @@ public final class StringFormatter {
      * @param input The string to add quotes to
      * @return The quoted string
      */
-    public static String quoteMultiWordString(String input) {
-        return input.contains(" ") ? "\"" + input + "\"" : input;
+    @Contract("null -> null")
+    public static @Nullable String quoteMultiWordString(@Nullable String input) {
+        return input != null && input.contains(" ") ? "\"" + input + "\"" : input;
+    }
+
+    /**
+     * Parses a CSV string of key=value pairs into a map.
+     * E.g. "key1=value1,key2=value2" -> {key1=value1, key2=value2}
+     *
+     * @param input The CSV string to parse
+     * @return The parsed map
+     *
+     * @since 5.5
+     */
+    @ApiStatus.AvailableSince("5.5")
+    public static @Unmodifiable Map<String, String> parseCSVMap(@Nullable String input) {
+        if (Strings.isNullOrEmpty(input)) {
+            return Map.of();
+        }
+        return REPatterns.COMMA.splitAsStream(input)
+                .map(s -> REPatterns.EQUALS.split(s, 2))
+                .filter(parts -> parts.length == 2)
+                .collect(Collectors.toUnmodifiableMap(parts -> parts[0], parts -> parts[1]));
     }
 }

src/main/java/org/mvplugins/multiverse/core/utils/WorldTickDeferrer.java

@@ -1,7 +1,7 @@
 package org.mvplugins.multiverse.core.utils;
 
 import com.dumptruckman.minecraft.util.Logging;
-import io.vavr.control.Try;
+import io.vavr.control.Option;
 import jakarta.inject.Inject;
 import org.bukkit.Server;
 import org.bukkit.scheduler.BukkitRunnable;
@@ -10,8 +10,6 @@ import org.jvnet.hk2.annotations.Service;
 import org.mvplugins.multiverse.core.MultiverseCore;
 
 import java.lang.reflect.Field;
-import java.lang.reflect.Method;
-import java.util.Objects;
 
 /**
  * Defers action that cannot be done during world tick.
@@ -21,26 +19,22 @@ public final class WorldTickDeferrer {
 
     private final MultiverseCore plugin;
 
-    private Object console = null;
-    private Field isIteratingOverLevelsMethod = null;
+    private final Option<Object> console;
+    private final Option<Field> isIteratingOverLevelsMethod;
 
     @Inject
     WorldTickDeferrer(@NotNull MultiverseCore plugin, @NotNull Server server) {
         this.plugin = plugin;
-        Method getServerMethod = ReflectHelper.getMethod(server.getClass(), "getServer");
-        if (getServerMethod == null) {
-            Logging.fine("Unable to find getServer method.");
-            return;
-        }
-        this.console = ReflectHelper.invokeMethod(server, getServerMethod);
-        if (console == null) {
-            Logging.fine("Unable to find console.");
-            return;
-        }
-        this.isIteratingOverLevelsMethod = Try.of(() -> console.getClass().getField("isIteratingOverLevels")).getOrNull();
-        if (isIteratingOverLevelsMethod == null) {
-            Logging.fine("Unable to find isIteratingOverLevels field.");
-        }
+        this.console = ReflectHelper.tryGetMethod(server.getClass(), "getServer")
+                .onFailure(throwable -> Logging.fine("Unable to find getServer method."))
+                .flatMap(getServerMethod -> ReflectHelper.tryInvokeMethod(server, getServerMethod))
+                .onFailure(throwable -> Logging.fine("Unable to find console."))
+                .toOption();
+        this.isIteratingOverLevelsMethod = console.toTry()
+                .map(Object::getClass)
+                .flatMap(consoleClazz -> ReflectHelper.tryGetField(consoleClazz, "isIteratingOverLevels"))
+                .onFailure(throwable -> Logging.fine("Unable to find isIteratingOverLevels field."))
+                .toOption();
     }
 
     /**
@@ -63,16 +57,14 @@ public final class WorldTickDeferrer {
     }
 
     /**
-     * Check if the the server is currently doing a world tick.
+     * Check if the server is currently doing a world tick.
      *
      * @return True if the server is currently doing a world tick
      */
     private boolean isIteratingOverLevels() {
-        if (console == null || isIteratingOverLevelsMethod == null) {
-            return false;
-        }
-        return Objects.requireNonNullElse(
-                ReflectHelper.getFieldValue(console, isIteratingOverLevelsMethod, Boolean.class),
-                false);
+        return isIteratingOverLevelsMethod
+                .flatMap(field -> console
+                        .flatMap(c -> ReflectHelper.tryGetFieldValue(c, field, Boolean.class).toOption()))
+                .getOrElse(false);
     }
 }

src/main/java/org/mvplugins/multiverse/core/utils/compatibility/BukkitCompatibility.java

@@ -0,0 +1,123 @@
+package org.mvplugins.multiverse.core.utils.compatibility;
+
+import io.vavr.control.Option;
+import io.vavr.control.Try;
+import org.bukkit.Bukkit;
+import org.bukkit.NamespacedKey;
+import org.bukkit.Server;
+import org.bukkit.World;
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.NotNull;
+import org.mvplugins.multiverse.core.utils.ReflectHelper;
+import org.mvplugins.multiverse.core.world.key.WorldKeyOrName;
+
+import java.lang.reflect.Method;
+import java.nio.file.Path;
+
+/**
+ * Compatibility class used to handle API changes in {@link Bukkit} class.
+ *
+ * @since 5.6
+ */
+@ApiStatus.AvailableSince("5.6")
+public final class BukkitCompatibility {
+
+    private static final Try<Method> GET_LEVEL_DIRECTORY_METHOD;
+    private static final Try<Method> GET_WORLD_NAMESPACED_KEY_METHOD;
+
+    static {
+        GET_LEVEL_DIRECTORY_METHOD = ReflectHelper.tryGetMethod(Server.class, "getLevelDirectory");
+        GET_WORLD_NAMESPACED_KEY_METHOD = ReflectHelper.tryGetMethod(Bukkit.class, "getWorld", NamespacedKey.class);
+    }
+
+    /**
+     * Check whether the server is using the new dimension storage system introduced in PaperMC 26.1.
+     * <br />
+     * This is based of whether getLevelDirectory method exists in the server class,which is the main API change for
+     * the new dimension storage system.
+     *
+     * @return True if the server is using the new dimension storage system, else false.
+     *
+     * @since 5.6
+     */
+    @ApiStatus.AvailableSince("5.6")
+    public static boolean isUsingNewDimensionStorage() {
+        return GET_LEVEL_DIRECTORY_METHOD
+                .flatMap(method -> ReflectHelper.tryInvokeMethod(Bukkit.getServer(), method))
+                .isSuccess();
+    }
+
+    /**
+     * Gets the folder where all the worlds will be store. Before 26.1, all worlds are stored in the root directory
+     * of the server, which can be obtained by {@link Server#getWorldContainer()}.
+     * <br />
+     * After 26.1, PaperMC changed all worlds are stored in the "[level]/dimensions" folder under the world
+     * level directory, which needs to be manually parsed.
+     *
+     * @return The location where all the worlds folders should be, depending on server's mc version.
+     *
+     * @since 5.6
+     */
+    @ApiStatus.AvailableSince("5.6")
+    @NotNull
+    public static Path getWorldFoldersDirectory() {
+        Server server = Bukkit.getServer();
+        return GET_LEVEL_DIRECTORY_METHOD.flatMap(method -> ReflectHelper.tryInvokeMethod(server, method))
+                .filter(Path.class::isInstance)
+                .map(Path.class::cast)
+                .map(path -> path.resolve("dimensions"))
+                .getOrElse(() -> server.getWorldContainer().toPath());
+    }
+
+    /**
+     * Check if the world with the given name or namespaced key (e.g. minecraft:overworld) exists,
+     * and return it if it does.
+     * <br />
+     * Note that some default world names have different namespaced key matched with them.
+     * E.g.: world -> minecraft:overworld, world_nether -> minecraft:the_nether, world_the_end -> minecraft:the_end.
+     *
+     * @param nameOrKey Either a name or namespaced key string representation.
+     * @return The world if it exists
+     *
+     * @since 5.6
+     */
+    @ApiStatus.AvailableSince("5.6")
+    @NotNull
+    public static Option<World> getWorldByNameOrKey(@NotNull String nameOrKey) {
+        return Option.of(Bukkit.getWorld(nameOrKey))
+                .orElse(() -> GET_WORLD_NAMESPACED_KEY_METHOD
+                        .flatMap(method -> ReflectHelper.tryInvokeStaticMethod(method, NamespacedKey.fromString(nameOrKey)))
+                        .filter(World.class::isInstance)
+                        .map(World.class::cast)
+                        .toOption());
+    }
+
+
+    /**
+     * Check if the world represented by the given {@link WorldKeyOrName} exists and return it if present.
+     *
+     * <p>This first attempts to resolve the world by name using {@link WorldKeyOrName#usableName()} (which
+     * delegates to the traditional Bukkit world name lookup). If that fails it will attempt to resolve a
+     * {@link NamespacedKey} using {@link WorldKeyOrName#usableKey()} (which mirrors the newer Bukkit API
+     * that accepts namespaced keys, e.g. "minecraft:overworld").
+     *
+     * @param keyOrName The key-or-name wrapper providing either a world name or a {@link NamespacedKey}.
+     * @return The world if it exists.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    @NotNull
+    public static Option<World> getWorldByNameOrKey(@NotNull WorldKeyOrName keyOrName) {
+        return Option.of(Bukkit.getWorld(keyOrName.usableName()))
+                .orElse(() -> GET_WORLD_NAMESPACED_KEY_METHOD
+                        .flatMap(method -> ReflectHelper.tryInvokeStaticMethod(method, keyOrName.usableKey()))
+                        .filter(World.class::isInstance)
+                        .map(World.class::cast)
+                        .toOption());
+    }
+
+    private BukkitCompatibility() {
+        throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
+    }
+}

src/main/java/org/mvplugins/multiverse/core/utils/compatibility/UnsafeValuesCompatibility.java

@@ -0,0 +1,45 @@
+package org.mvplugins.multiverse.core.utils.compatibility;
+
+import io.vavr.control.Option;
+import io.vavr.control.Try;
+import org.bukkit.Bukkit;
+import org.bukkit.UnsafeValues;
+import org.jetbrains.annotations.ApiStatus;
+import org.mvplugins.multiverse.core.utils.ReflectHelper;
+
+import java.lang.reflect.Method;
+
+/**
+ * Compatibility class used to handle API changes in {@link UnsafeValues} class.
+ *
+ * @since 5.6
+ */
+@ApiStatus.AvailableSince("5.7")
+public final class UnsafeValuesCompatibility {
+
+    private static final Try<Method> GET_MAIN_LEVEL_NAME_METHOD;
+
+    static {
+        GET_MAIN_LEVEL_NAME_METHOD = ReflectHelper.tryGetMethod(UnsafeValues.class, "getMainLevelName");
+    }
+
+    /**
+     * Try to call the getMainLevelName method in UnsafeValues, which is used to get level-name configured in
+     * server.properties file.
+     *
+     * @return The level-name configured in server.properties file, or empty if the method is not available.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static Option<String> getMainLevelName() {
+        return GET_MAIN_LEVEL_NAME_METHOD
+                .flatMap(method -> ReflectHelper.tryInvokeMethod(Bukkit.getUnsafe(), method))
+                .map(String.class::cast)
+                .toOption();
+    }
+
+    private UnsafeValuesCompatibility() {
+        throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
+    }
+}

src/main/java/org/mvplugins/multiverse/core/utils/compatibility/WorldBorderCompatibility.java

@@ -0,0 +1,170 @@
+package org.mvplugins.multiverse.core.utils.compatibility;
+
+import org.bukkit.WorldBorder;
+import org.jetbrains.annotations.ApiStatus;
+import org.mvplugins.multiverse.core.utils.ReflectHelper;
+import org.mvplugins.multiverse.core.utils.tick.TickDuration;
+
+import java.util.concurrent.TimeUnit;
+
+/**
+ * Compatibility class used to handle API changes in {@link WorldBorder} class.
+ *
+ * @since 5.7
+ */
+@ApiStatus.AvailableSince("5.7")
+@SuppressWarnings("removal")
+public final class WorldBorderCompatibility {
+
+    private static final boolean HAS_GET_WARNING_TIME_TICKS_METHOD;
+    private static final boolean HAS_SET_WARNING_TIME_TICKS_METHOD;
+    private static final boolean HAS_SET_WARNING_TIME_METHOD;
+    private static final boolean HAS_GET_WARNING_TIME_METHOD;
+
+    private static final boolean HAS_CHANGE_SIZE_METHOD;
+    private static final boolean HAS_SET_SIZE_METHOD;
+
+    static {
+        HAS_GET_WARNING_TIME_TICKS_METHOD = ReflectHelper.hasMethod(WorldBorder.class, "getWarningTimeTicks");
+        HAS_SET_WARNING_TIME_TICKS_METHOD = ReflectHelper.hasMethod(WorldBorder.class, "setWarningTimeTicks", int.class);
+        HAS_GET_WARNING_TIME_METHOD = ReflectHelper.hasMethod(WorldBorder.class, "getWarningTime");
+        HAS_SET_WARNING_TIME_METHOD = ReflectHelper.hasMethod(WorldBorder.class, "setWarningTime", int.class);
+
+        HAS_CHANGE_SIZE_METHOD = ReflectHelper.hasMethod(WorldBorder.class, "changeSize", double.class, long.class);
+        HAS_SET_SIZE_METHOD = ReflectHelper.hasMethod(WorldBorder.class, "setSize", double.class, long.class);
+    }
+
+    /**
+     * Gets the world border warning time in ticks, using the most precise API available.
+     * <br />
+     * If the server exposes {@code getWarningTimeTicks()}, that value is returned directly. Otherwise, the older
+     * {@code getWarningTime()} API is used and converted from seconds to ticks.
+     *
+     * @param worldBorder The world border to query.
+     * @return The warning time in ticks.
+     *
+     * @since 5.7
+     * @throws IllegalStateException If neither warning-time getter is available.
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static int getWarningTimeTicks(WorldBorder worldBorder) {
+        if (HAS_GET_WARNING_TIME_TICKS_METHOD) {
+            return worldBorder.getWarningTimeTicks();
+        } else if (HAS_GET_WARNING_TIME_METHOD) {
+            return worldBorder.getWarningTime() * 20;
+        }
+        throw new IllegalStateException("Neither getWarningTimeTicks nor getWarningTime method is available in WorldBorder class.");
+    }
+
+    /**
+     * Gets the world border warning time in seconds, using the most appropriate API available.
+     * <br />
+     * If the server exposes {@code getWarningTimeTicks()}, that value is converted from ticks to seconds. Otherwise,
+     * the older {@code getWarningTime()} API is used directly.
+     *
+     * @param worldBorder The world border to query.
+     * @return The warning time in seconds.
+     *
+     * @since 5.7
+     * @throws IllegalStateException If neither warning-time getter is available.
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static double getWarningTime(WorldBorder worldBorder) {
+        if (HAS_GET_WARNING_TIME_TICKS_METHOD) {
+            return (double) worldBorder.getWarningTimeTicks() / 20.0;
+        } else if (HAS_GET_WARNING_TIME_METHOD) {
+            return worldBorder.getWarningTime();
+        }
+        throw new IllegalStateException("Neither getWarningTimeTicks nor getWarningTime method is available in WorldBorder class.");
+    }
+
+    /**
+     * Checks whether the current server supports setting the world border warning time in ticks.
+     *
+     * @return True if {@code setWarningTimeTicks(int)} is available, else false.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static boolean supportsSetWarningTimeInTicks() {
+        return HAS_SET_WARNING_TIME_TICKS_METHOD;
+    }
+
+    /**
+     * Sets the world border warning time in ticks.
+     * <br />
+     * This is a convenience wrapper around {@link #setWarningTimeDuration(WorldBorder, TickDuration)} that converts
+     * the given tick value into a {@link TickDuration} first.
+     *
+     * @param worldBorder   The world border to update.
+     * @param ticks         The warning time in ticks.
+     *
+     * @since 5.7
+     */
+    public static void setWarningTimeTicks(WorldBorder worldBorder, int ticks) {
+        setWarningTimeDuration(worldBorder, TickDuration.ofTicks(ticks));
+    }
+
+    /**
+     * Sets the world border warning time, preferring tick-based APIs when available.
+     * <br />
+     * If the server supports {@code setWarningTimeTicks(int)}, the provided duration is applied in ticks. Otherwise,
+     * the older {@code setWarningTime(int)} API is used and the duration is converted to seconds.
+     *
+     * @param worldBorder   The world border to update.
+     * @param duration      The warning duration to apply.
+     *
+     * @since 5.7
+     * @throws IllegalStateException If neither warning-time setter is available.
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static void setWarningTimeDuration(WorldBorder worldBorder, TickDuration duration) {
+        if (HAS_SET_WARNING_TIME_TICKS_METHOD) {
+            worldBorder.setWarningTimeTicks((int) duration.toTicks());
+        } else if (HAS_SET_WARNING_TIME_METHOD) {
+            worldBorder.setWarningTime((int) Math.round(duration.to(TimeUnit.SECONDS)));
+        } else {
+            throw new IllegalStateException("Neither setWarningTimeTicks nor setWarningTime method is available in WorldBorder class.");
+        }
+    }
+
+    /**
+     * Checks whether the current server supports changing world border size over a duration in ticks.
+     *
+     * @return True if {@code changeSize(double, long)} is available, else false.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static boolean supportsChangeSizeInTicks() {
+        return HAS_CHANGE_SIZE_METHOD;
+    }
+
+    /**
+     * Changes the world border size, preferring the tick-based API when available.
+     * <br />
+     * If the server supports {@code changeSize(double, long)}, the size change is applied in ticks. Otherwise, the
+     * older {@code setSize(double, long)} API is used and the duration is converted to seconds.
+     *
+     * @param worldBorder   The world border to update.
+     * @param newSize       The new border size.
+     * @param duration      The transition duration to apply.
+     *
+     * @since 5.7
+     * @throws IllegalStateException If neither size-changing API is available.
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static void changeSizeDuration(WorldBorder worldBorder, double newSize, TickDuration duration) {
+        if (HAS_CHANGE_SIZE_METHOD) {
+            worldBorder.changeSize(newSize, duration.toTicks());
+        } else if (HAS_SET_SIZE_METHOD) {
+            worldBorder.setSize(newSize, Math.round(duration.to(TimeUnit.SECONDS)));
+        } else {
+            throw new IllegalStateException("Neither changeSize nor setSize method is available in WorldBorder class.");
+        }
+    }
+
+    private WorldBorderCompatibility() {
+        throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
+    }
+}

src/main/java/org/mvplugins/multiverse/core/utils/compatibility/WorldCompatibility.java

@@ -0,0 +1,92 @@
+package org.mvplugins.multiverse.core.utils.compatibility;
+
+import io.papermc.lib.PaperLib;
+import io.vavr.control.Try;
+import org.bukkit.World;
+import org.jetbrains.annotations.ApiStatus;
+import org.mvplugins.multiverse.core.utils.ReflectHelper;
+
+import java.lang.reflect.Method;
+
+/**
+ * Compatibility class used to handle API changes in {@link World} class.
+ *
+ * @since 5.7
+ */
+@ApiStatus.AvailableSince("5.7")
+public final class WorldCompatibility {
+
+    private static final Try<Method> SAVE_WITH_FLUSH_METHOD;
+    private static final boolean HAS_GET_COORDINATE_SCALE_METHOD;
+    private static final boolean HAS_HAS_BONUS_CHEST_METHOD;
+
+    static {
+        SAVE_WITH_FLUSH_METHOD = ReflectHelper.tryGetMethod(World.class, "save", boolean.class);
+        HAS_GET_COORDINATE_SCALE_METHOD = ReflectHelper.hasMethod(World.class, "getCoordinateScale");
+        HAS_HAS_BONUS_CHEST_METHOD = ReflectHelper.hasMethod(World.class, "hasBonusChest");
+    }
+
+    /**
+     * Saves the world, with an option to wait for chunk writers to finish if the method is available. Saving with
+     * flush is only supported on PaperMC 1.21+.
+     * <br />
+     * If the method is not available, it will fall back to the normal save method, which may not wait for chunk writers
+     * to finish, but is the best we can do for older versions of Minecraft.
+     *
+     * @param world The world to save
+     * @param flush Waits for chunk writers to finish
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static void saveWithFlush(World world, boolean flush) {
+        SAVE_WITH_FLUSH_METHOD
+                .flatMap(method -> ReflectHelper.tryInvokeMethod(world, method, flush))
+                .orElseRun(ignore -> world.save());
+    }
+
+    /**
+     * Gets the coordinate scale for the world, which is used to convert between overworld and nether coordinates.
+     * On PaperMC, this can be obtained directly from the API. On older versions, it is manually determined based on the
+     * world environment (overworld = 1, nether = 8, end = 1).
+     *
+     * @param world The world to get the coordinate scale for
+     * @return The scale
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static double getCoordinateScale(World world) {
+        if (HAS_GET_COORDINATE_SCALE_METHOD) {
+            return world.getCoordinateScale();
+        }
+        return switch (world.getEnvironment()) {
+            case NORMAL -> 1;
+            case NETHER -> 8;
+            default -> 1;
+        };
+    }
+
+    /**
+     * Checks if the world has a bonus chest.
+     * <br />
+     * On PaperMC 1.21.5+, this can be obtained directly from the API. On older versions, it always returns false as
+     * bonus chest is not supported.
+     *
+     * @param world The world to check
+     * @return True if the world has a bonus chest, false otherwise
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static boolean hasBonusChest(World world) {
+        if (HAS_HAS_BONUS_CHEST_METHOD) {
+            return world.hasBonusChest();
+        }
+        return false;
+    }
+
+    private WorldCompatibility() {
+        throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
+    }
+}

src/main/java/org/mvplugins/multiverse/core/utils/compatibility/WorldCreatorCompatibility.java

@@ -0,0 +1,188 @@
+package org.mvplugins.multiverse.core.utils.compatibility;
+
+import com.dumptruckman.minecraft.util.Logging;
+import io.vavr.control.Try;
+import org.bukkit.NamespacedKey;
+import org.bukkit.WorldCreator;
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.NotNull;
+import org.mvplugins.multiverse.core.utils.ReflectHelper;
+import org.mvplugins.multiverse.core.utils.position.EntityPosition;
+import org.mvplugins.multiverse.core.world.key.WorldKeyOrName;
+
+import java.lang.reflect.Method;
+import java.util.Locale;
+
+/**
+ * Compatibility class used to handle {@link WorldCreator} API changes across different server versions.
+ *
+ * @since 5.7
+ */
+@ApiStatus.AvailableSince("5.7")
+public final class WorldCreatorCompatibility {
+
+    private static final Try<Class<?>> POSITION_CLASS;
+    private static final Try<Method> FORCED_SPAWN_POSITION_METHOD;
+    private static final Try<Method> OF_KEY_METHOD;
+    private static final Try<Method> OF_NAME_AND_KEY_METHOD;
+    private static final Try<Method> BONUS_CHEST_METHOD;
+
+    static {
+        POSITION_CLASS = ReflectHelper.tryGetClass("io.papermc.paper.math.Position");
+        FORCED_SPAWN_POSITION_METHOD = POSITION_CLASS.flatMap(positionClass ->
+                ReflectHelper.tryGetMethod(WorldCreator.class, "forcedSpawnPosition", positionClass, float.class, float.class));
+        BONUS_CHEST_METHOD = ReflectHelper.tryGetMethod(WorldCreator.class, "bonusChest", boolean.class);
+        OF_KEY_METHOD = ReflectHelper.tryGetMethod(WorldCreator.class, "ofKey", NamespacedKey.class);
+        OF_NAME_AND_KEY_METHOD = ReflectHelper.tryGetMethod(WorldCreator.class, "ofNameAndKey", String.class, NamespacedKey.class);
+    }
+
+    /**
+     * Check whether the current server version supports creating worlds with a {@link NamespacedKey}.
+     * <br />
+     * This is based on whether the {@code ofKey(NamespacedKey)} method exists in the {@link WorldCreator} class,
+     * which was introduced in later server versions.
+     *
+     * @return True if the server supports world creation with NamespacedKey, else false.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static boolean canCreateWorldWithKey() {
+        return OF_KEY_METHOD.isSuccess();
+    }
+
+    /**
+     * Creates a {@link WorldCreator} from a {@link WorldKeyOrName}, using the most appropriate method
+     * based on the server version and the key/name state.
+     * <br />
+     * If the server supports NamespacedKey-based creation and the provided keyOrName is a key,
+     * this method will use {@code ofKey()}. Otherwise, it falls back to {@code name()}.
+     *
+     * @param keyOrName Either a world key or name to create from.
+     * @return The {@link WorldCreator} initialized for the given key or name.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static WorldCreator ofKeyOrName(@NotNull WorldKeyOrName keyOrName) {
+        return ofNameAndKey(keyOrName.usableKey(), keyOrName.usableName());
+    }
+
+    /**
+     * Creates a {@link WorldCreator} from a {@link NamespacedKey} and world name, using the most
+     * appropriate method based on the server version and dimension storage configuration.
+     * <br />
+     * This method attempts to use the most feature-rich creation method available:
+     * if {@code ofNameAndKey()} is available and the parameters are compatible, use it;
+     * otherwise, if {@code ofKey()} is available, use it; as a fallback, use {@code name()}.
+     *
+     * @param worldKey The namespaced key for the world.
+     * @param worldName The display name for the world.
+     * @return The {@link WorldCreator} initialized with the given key and name.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static WorldCreator ofNameAndKey(@NotNull NamespacedKey worldKey, String worldName) {
+        if (OF_NAME_AND_KEY_METHOD.isSuccess() && canPassIntoNameAndKey(worldKey)) {
+            return WorldCreator.ofNameAndKey(worldName, worldKey);
+        }
+        if  (OF_KEY_METHOD.isSuccess()) {
+            return WorldCreator.ofKey(worldKey);
+        }
+        return WorldCreator.name(worldName);
+    }
+
+    /**
+     * Check if the given world key and name can be passed into the {@code ofNameAndKey()} method.
+     * <br />
+     * The parameters are compatible only if the server is not using new dimension storage,
+     * or if the namespace is the Minecraft namespace and the world name (lowercased) matches the key.
+     *
+     * @param worldKey The namespaced key for the world.
+     * @return True if the parameters can be safely passed to {@code ofNameAndKey()}, else false.
+     */
+    private static boolean canPassIntoNameAndKey(@NotNull NamespacedKey worldKey) {
+        return !BukkitCompatibility.isUsingNewDimensionStorage()
+                || worldKey.getNamespace().equals(NamespacedKey.MINECRAFT);
+    }
+
+    /**
+     * Checks if the server supports configuring a forced spawn position via the WorldCreator API.
+     * <br />
+     * The force spawn position API is generally only available on PaperMC 26.1+
+     *
+     * @return Whether force spawn position API is supported on the current server version.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static boolean supportsForcedSpawnPosition() {
+        return FORCED_SPAWN_POSITION_METHOD.isSuccess();
+    }
+
+    /**
+     * Tries to set the forced spawn position if the server implements the API. This call will do nothing if server
+     * software does not implement the required APIs.
+     *
+     * @param worldCreator  Target creator instance to set on.
+     * @param position      The position to set as the forced spawn point for the world.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static void setForcedSpawnPosition(WorldCreator worldCreator, EntityPosition position) {
+        if (!supportsForcedSpawnPosition()) {
+            Logging.fine("Server does not support forced spawn position configuration via WorldCreator API.");
+            return;
+        }
+        ReflectHelper.tryInvokeMethod(
+                worldCreator,
+                FORCED_SPAWN_POSITION_METHOD.get(),
+                io.papermc.paper.math.Position.fine(
+                        position.getVector().getX().getRawValue(),
+                        position.getVector().getY().getRawValue(),
+                        position.getVector().getZ().getRawValue()
+                ),
+                (float) position.getDirection().getYaw().getRawValue(),
+                (float) position.getDirection().getPitch().getRawValue()
+        ).onFailure(ex ->
+                Logging.warning("Failed to set forced spawn position on WorldCreator: %s", ex.getMessage()));
+    }
+
+    /**
+     * Checks if the server supports configuring bonus chest generation via the WorldCreator API.
+     * <br />
+     * The bonus chest API is generally only available on PaperMC 1.21.5+
+     *
+     * @return Whether bonus chest API is supported on the current server version.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static boolean supportsBonusChest() {
+        return BONUS_CHEST_METHOD.isSuccess();
+    }
+
+    /**
+     * Tries to set bonus chest if the server implements the API. This call will do nothing if server software does not
+     * implement the required APIs.
+     *
+     * @param worldCreator          Target creator instance to set on.
+     * @param generateBonusChest    Whether to generate a bonus chest at the world spawn point.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static void setBonusChest(WorldCreator worldCreator, boolean generateBonusChest) {
+        if (!supportsBonusChest()) {
+            Logging.fine("Server does not support bonus chest generation via WorldCreator API.");
+            return;
+        }
+        worldCreator.bonusChest(generateBonusChest);
+    }
+
+    private WorldCreatorCompatibility() {
+        throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
+    }
+}

src/main/java/org/mvplugins/multiverse/core/utils/compatibility/package-info.java

@@ -0,0 +1,5 @@
+/**
+ * Contains classes to handle compatibility due to differing API methods across different server versions and the
+ * API gaps between PaperMC and Spigot.
+ */
+package org.mvplugins.multiverse.core.utils.compatibility;

src/main/java/org/mvplugins/multiverse/core/utils/result/Attempt.java

@@ -2,6 +2,7 @@ package org.mvplugins.multiverse.core.utils.result;
 
 import java.util.function.Consumer;
 import java.util.function.Function;
+import java.util.function.Predicate;
 import java.util.function.Supplier;
 
 import io.vavr.control.Either;
@@ -19,6 +20,38 @@ import org.mvplugins.multiverse.core.locale.message.MessageReplacement;
  */
 public sealed interface Attempt<T, F extends FailureReason> permits Attempt.Success, Attempt.Failure {
 
+    /**
+     * Creates a new success attempt.
+     *
+     * @param value The value.
+     * @param <T>   The type of the value.
+     * @param <F>   The type of failure reason.
+     * @return The new success attempt.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    static <T, F extends FailureReason> Attempt.Success<T, F> successRef(T value) {
+        return new Success<>(value);
+    }
+
+    /**
+     * Creates a new failure attempt.
+     *
+     * @param failureReason         The reason for failure.
+     * @param messageReplacements   The replacements for the failure message.
+     * @param <T>                   The type of the value.
+     * @param <F>                   The type of failure reason.
+     * @return The new failure attempt.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    static <T, F extends FailureReason> Attempt.Failure<T, F> failureRef(
+            F failureReason, MessageReplacement... messageReplacements) {
+        return new Failure<>(failureReason, Message.of(failureReason, "Failed!", messageReplacements));
+    }
+
     /**
      * Creates a new success attempt.
      *
@@ -28,7 +61,7 @@ public sealed interface Attempt<T, F extends FailureReason> permits Attempt.Succ
      * @return The new success attempt.
      */
     static <T, F extends FailureReason> Attempt<T, F> success(T value) {
-        return new Success<>(value);
+        return successRef(value);
     }
 
     /**
@@ -42,7 +75,7 @@ public sealed interface Attempt<T, F extends FailureReason> permits Attempt.Succ
      */
     static <T, F extends FailureReason> Attempt<T, F> failure(
             F failureReason, MessageReplacement... messageReplacements) {
-        return new Failure<>(failureReason, Message.of(failureReason, "Failed!", messageReplacements));
+        return failureRef(failureReason, messageReplacements);
     }
 
     /**
@@ -203,6 +236,33 @@ public sealed interface Attempt<T, F extends FailureReason> permits Attempt.Succ
      */
     <U> Attempt<U, F> mapAttempt(Supplier<Attempt<U, F>> mapper);
 
+    /**
+     * Fails this attempt with the given failure attempt if the value matches the given predicate.This will do nothing
+     * if this is already a failure attempt.
+     *
+     * @param predicate         The predicate to test the value.
+     * @param failureAttempt    The failure attempt to return if the predicate matches.
+     * @return The new attempt
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    Attempt<T, F> failIf(Predicate<? super T> predicate, Supplier<Attempt.Failure<T, F>> failureAttempt);
+
+    /**
+     * Fails this attempt with the given failure attempt if the value matches the given predicate.This will do nothing
+     * if this is already a failure attempt.
+     *
+     * @param predicate         The predicate to test the value.
+     * @param failureAttempt    The failure attempt to return if the predicate matches, which can be generated based
+     *                          on the value.
+     * @return The new attempt
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    Attempt<T, F> failIf(Predicate<? super T> predicate, Function<? super T, Attempt.Failure<T, F>> failureAttempt);
+
     /**
      * Maps to another attempt with a different fail reason.
      *
@@ -370,6 +430,16 @@ public sealed interface Attempt<T, F extends FailureReason> permits Attempt.Succ
             return mapper.get();
         }
 
+        @Override
+        public Attempt<T, F> failIf(Predicate<? super T> predicate, Supplier<Attempt.Failure<T, F>> failureAttempt) {
+            return predicate.test(value) ? failureAttempt.get() : this;
+        }
+
+        @Override
+        public Attempt<T, F> failIf(Predicate<? super T> predicate, Function<? super T, Failure<T, F>> failureAttempt) {
+            return predicate.test(value) ? failureAttempt.apply(value) : this;
+        }
+
         @Override
         public <UF extends FailureReason> Attempt<T, UF> transform(UF failureReason) {
             return changeFailureType();
@@ -532,6 +602,16 @@ public sealed interface Attempt<T, F extends FailureReason> permits Attempt.Succ
             return changeValueType();
         }
 
+        @Override
+        public Attempt<T, F> failIf(Predicate<? super T> predicate, Supplier<Attempt.Failure<T, F>> failureAttempt) {
+            return this;
+        }
+
+        @Override
+        public Attempt<T, F> failIf(Predicate<? super T> predicate, Function<? super T, Failure<T, F>> failureAttempt) {
+            return this;
+        }
+
         @Override
         public <UF extends FailureReason> Attempt<T, UF> transform(UF failureReason) {
             return new Failure<>(failureReason, getFailureMessage(), this);

src/main/java/org/mvplugins/multiverse/core/utils/tick/TickDuration.java

@@ -0,0 +1,274 @@
+package org.mvplugins.multiverse.core.utils.tick;
+
+import io.vavr.control.Try;
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.Contract;
+import org.jetbrains.annotations.NotNull;
+
+import java.time.Duration;
+import java.time.LocalTime;
+import java.time.temporal.TemporalUnit;
+import java.util.concurrent.TimeUnit;
+
+/**
+ * Represents a duration in Minecraft game ticks.
+ * <p>
+ * This class wraps a {@link Duration} and provides convenient conversion methods
+ * between game ticks (50ms per tick), game days (24,000 ticks), and other time units.
+ * Game time is mapped to real-world seconds via: realSeconds = (ticks * 3.6) + 6*3600 (mod 24h),
+ * which means 00:00 maps to 06:00 in-game time.
+ * </p>
+ *
+ * @since 5.7
+ */
+@ApiStatus.AvailableSince("5.7")
+public final class TickDuration {
+
+    /**
+     * Parses a time string into a {@link TickDuration}.
+     * <br />
+     * Formats supported:
+     * <ul>
+     *   <li>{@code "123"} - raw tick count</li>
+     *   <li>{@code "10s"} - seconds</li>
+     *   <li>{@code "5d"} - game days</li>
+     * </ul>
+     *
+     * @param timeString the time string to parse
+     * @return a {@link Try} containing the parsed {@link TickDuration}, or a failure if parsing fails
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static Try<TickDuration> parseString(@NotNull String timeString) {
+        return Try.of(() -> {
+            if (timeString.endsWith("s")) {
+                String subString = timeString.substring(0, timeString.length() - 1);
+                return of(Long.parseLong(subString), TimeUnit.SECONDS);
+            } else if (timeString.endsWith("d")) {
+                String subString = timeString.substring(0, timeString.length() - 1);
+                return ofGameDays(Long.parseLong(subString));
+            }
+            return ofTicks(Long.parseLong(timeString));
+        });
+    }
+
+    /**
+     * Creates a {@link TickDuration} from a {@link Duration}.
+     *
+     * @param duration the duration
+     * @return a new {@link TickDuration}
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    @Contract(value = "_ -> new", pure = true)
+    public static @NotNull TickDuration ofDuration(@NotNull Duration duration) {
+        return new TickDuration(duration);
+    }
+
+    /**
+     * Creates a {@link TickDuration} from seconds (as a {@link Duration}).
+     *
+     * @param duration the duration representing seconds
+     * @return a new {@link TickDuration}
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    @Contract(value = "_ -> new", pure = true)
+    public static @NotNull TickDuration ofSeconds(@NotNull Duration duration) {
+        return new TickDuration(duration);
+    }
+
+    /**
+     * Creates a {@link TickDuration} from a tick count.
+     *
+     * @param ticks the number of game ticks
+     * @return a new {@link TickDuration}
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    @Contract(value = "_ -> new", pure = true)
+    public static @NotNull TickDuration ofTicks(long ticks) {
+        return of(ticks, TickUnit.TICK);
+    }
+
+    /**
+     * Creates a {@link TickDuration} from a game day count.
+     *
+     * @param gameDays the number of game days (24,000 ticks each)
+     * @return a new {@link TickDuration}
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    @Contract(value = "_ -> new", pure = true)
+    public static @NotNull TickDuration ofGameDays(long gameDays) {
+        return of(gameDays, TickUnit.GAME_DAY);
+    }
+
+    /**
+     * Creates a {@link TickDuration} from a time value and {@link TimeUnit}.
+     *
+     * @param time the time value
+     * @param unit the time unit
+     * @return a new {@link TickDuration}
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    @Contract(value = "_, _ -> new", pure = true)
+    public static @NotNull TickDuration of(long time, @NotNull TimeUnit unit) {
+        return of(time, unit.toChronoUnit());
+    }
+
+    /**
+     * Creates a {@link TickDuration} from a time value and {@link TemporalUnit}.
+     *
+     * @param time the time value
+     * @param unit the temporal unit
+     * @return a new {@link TickDuration}
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    @Contract(value = "_, _ -> new", pure = true)
+    public static @NotNull TickDuration of(long time, @NotNull TemporalUnit unit) {
+        return new TickDuration(Duration.of(time, unit));
+    }
+
+    private static final double TIME_MULTIPLIER = 3.6;
+    private static final long DAY_SECONDS = 24 * 60 * 60;
+    private static final long START_OFFSET = 6 * 60 * 60;
+
+    private final Duration duration;
+
+    /**
+     * Creates a {@link TickDuration} from a {@link Duration}.
+     *
+     * @param duration the underlying duration
+     */
+    private TickDuration(@NotNull Duration duration) {
+        this.duration = duration;
+    }
+
+    /**
+     * Converts this duration to Minecraft local time.
+     * <p>
+     * Maps the duration to real-world seconds using the formula:
+     * realSeconds = (ticks * 3.6) + 6*3600 (mod 24h)
+     * </p>
+     *
+     * @return the {@link LocalTime} in Minecraft time (where 00:00 = 06:00 in-game)
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public @NotNull LocalTime toLocalTime() {
+        // Minecraft maps ticks -> seconds by: realSeconds = (ticks * 3.6) + 6*3600 (mod 24h)
+        long realSeconds = (long) ((toTicks() * TIME_MULTIPLIER) + START_OFFSET) % DAY_SECONDS;
+        return LocalTime.ofSecondOfDay(realSeconds);
+    }
+
+    /**
+     * Converts this duration to game ticks.
+     *
+     * @return the number of game ticks (1 tick = 50ms)
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public long toTicks() {
+        return duration.toMillis() / TickUnit.TICK.inMillis();
+    }
+
+    /**
+     * Converts this duration to game days.
+     *
+     * @return the number of game days (1 day = 24,000 ticks)
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public double toGameDays() {
+        return (double) duration.toMillis() / (double) TickUnit.GAME_DAY.inMillis();
+    }
+
+    /**
+     * Converts this duration to seconds.
+     *
+     * @return the duration in seconds
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public double toSeconds() {
+        return to(TimeUnit.SECONDS);
+    }
+
+    /**
+     * Converts this duration to a specified {@link TimeUnit}.
+     *
+     * @param unit the target time unit
+     * @return the duration in the specified unit
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public double to(@NotNull TimeUnit unit) {
+        return to(unit.toChronoUnit());
+    }
+
+    /**
+     * Converts this duration to a specified {@link TemporalUnit}.
+     *
+     * @param unit the target temporal unit
+     * @return the duration in the specified unit
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public double to(@NotNull TemporalUnit unit) {
+        return (double) duration.toMillis() / (double) unit.getDuration().toMillis();
+    }
+
+    /**
+     * Checks whether this duration is an exact multiple of the given {@link TimeUnit}.
+     *
+     * @param unit the time unit to test against
+     * @return {@code true} if this duration divides evenly by the unit, otherwise {@code false}
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public boolean isExactTo(@NotNull TimeUnit unit) {
+        return isExactTo(unit.toChronoUnit());
+    }
+
+    /**
+     * Checks whether this duration is an exact multiple of the given {@link TemporalUnit}.
+     *
+     * @param unit the temporal unit to test against
+     * @return {@code true} if this duration divides evenly by the unit, otherwise {@code false}
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public boolean isExactTo(@NotNull TemporalUnit unit) {
+        return duration.toMillis() % unit.getDuration().toMillis() == 0;
+    }
+
+    /**
+     * Returns the underlying {@link Duration}.
+     *
+     * @return the duration
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public Duration getDuration() {
+        return duration;
+    }
+}

src/main/java/org/mvplugins/multiverse/core/utils/tick/TickUnit.java

@@ -0,0 +1,112 @@
+package org.mvplugins.multiverse.core.utils.tick;
+
+import org.jetbrains.annotations.ApiStatus;
+
+import java.time.Duration;
+import java.time.temporal.ChronoUnit;
+import java.time.temporal.Temporal;
+import java.time.temporal.TemporalUnit;
+
+/**
+ * A {@link TemporalUnit} implementation for Minecraft game ticks.
+ * <br />
+ * Provides two standard units:
+ * <ul>
+ *   <li>{@link #TICK} - A single game tick (50 milliseconds)</li>
+ *   <li>{@link #GAME_DAY} - A full game day (24,000 ticks)</li>
+ * </ul>
+ * This unit is not date-based and is precisely defined without estimation.
+ *
+ * @since 5.7
+ */
+@ApiStatus.AvailableSince("5.7")
+public final class TickUnit implements TemporalUnit {
+
+    private static final long SINGLE_TICK_DURATION_MS = 50L;
+    private static final long TICKS_PER_GAME_DAY = 24_000L;
+
+    /**
+     * A single game tick (50 milliseconds).
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static final TickUnit TICK = new TickUnit(SINGLE_TICK_DURATION_MS);
+
+    /**
+     * A full game day (24,000 ticks = 20 minutes in real time).
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static final TickUnit GAME_DAY = new TickUnit(SINGLE_TICK_DURATION_MS * TICKS_PER_GAME_DAY);
+
+    private final long milliseconds;
+    private final Duration duration;
+
+    private TickUnit(long milliseconds) {
+        this.milliseconds = milliseconds;
+        this.duration = Duration.ofMillis(milliseconds);
+    }
+
+    /**
+     * Gets the duration of this unit in milliseconds.
+     *
+     * @return the duration in milliseconds
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public long inMillis() {
+        return milliseconds;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public Duration getDuration() {
+        return duration;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public boolean isDurationEstimated() {
+        return false;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public boolean isDateBased() {
+        return false;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public boolean isTimeBased() {
+        return true;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @SuppressWarnings("unchecked") // following ChronoUnit#addTo
+    @Override
+    public <R extends Temporal> R addTo(R temporal, long amount) {
+        return (R) temporal.plus(duration.multipliedBy(amount));
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public long between(final Temporal start, final Temporal end) {
+        return start.until(end, ChronoUnit.MILLIS) / milliseconds;
+    }
+}

src/main/java/org/mvplugins/multiverse/core/utils/webpaste/HttpAPIClient.java

@@ -16,6 +16,9 @@ import javax.net.ssl.HttpsURLConnection;
  * HTTP API-client.
  */
 abstract sealed class HttpAPIClient permits PasteService, URLShortener {
+
+    static final String DUMPS_VIEWER_URL = "https://mvdumps.c0ding.party/";
+
     /**
      * The URL for this API-request, and if necessary, the access token.
      * If an access token is not necessary, it should be set to null.

src/main/java/org/mvplugins/multiverse/core/utils/webpaste/McloGsPasteService.java

@@ -34,7 +34,9 @@ final class McloGsPasteService extends PasteService {
     public String postData(String data) throws PasteFailedException {
         try {
             String stringJSON = this.exec(encodeData(data), ContentType.URLENCODED); // Execute request
-            return String.valueOf(((JSONObject) new JSONParser(JSONParser.DEFAULT_PERMISSIVE_MODE).parse(stringJSON)).get("url")); // Interpret result
+            return DUMPS_VIEWER_URL +
+                    ((JSONObject) new JSONParser(JSONParser.DEFAULT_PERMISSIVE_MODE).parse(stringJSON)).get("id") +
+                    "?service=mclogs";
         } catch (IOException | ParseException e) {
             throw new PasteFailedException(e);
         }
@@ -44,7 +46,9 @@ final class McloGsPasteService extends PasteService {
     public String postData(Map<String, String> data) throws PasteFailedException {
         try {
             String stringJSON = this.exec(encodeData(data), ContentType.JSON); // Execute request
-            return String.valueOf(((JSONObject) new JSONParser(JSONParser.DEFAULT_PERMISSIVE_MODE).parse(stringJSON)).get("url")); // Interpret result
+            return DUMPS_VIEWER_URL +
+                    ((JSONObject) new JSONParser(JSONParser.DEFAULT_PERMISSIVE_MODE).parse(stringJSON)).get("id") +
+                    "?service=mclogs";
         } catch (IOException | ParseException e) {
             throw new PasteFailedException(e);
         }

src/main/java/org/mvplugins/multiverse/core/utils/webpaste/PastebinPasteService.java

@@ -26,7 +26,7 @@ final class PastebinPasteService extends PasteService {
                 "&" + URLEncoder.encode("api_option", StandardCharsets.UTF_8) + "=" + URLEncoder.encode("paste", StandardCharsets.UTF_8) +
                 "&" + URLEncoder.encode("api_paste_code", StandardCharsets.UTF_8) + "=" + URLEncoder.encode(data, StandardCharsets.UTF_8) +
                 "&" + URLEncoder.encode("api_paste_private", StandardCharsets.UTF_8) + "=" + URLEncoder.encode(this.isPrivate ? "1" : "0", StandardCharsets.UTF_8) +
-                "&" + URLEncoder.encode("api_paste_format", StandardCharsets.UTF_8) + "=" + URLEncoder.encode("yaml", StandardCharsets.UTF_8) +
+                "&" + URLEncoder.encode("api_paste_format", StandardCharsets.UTF_8) + "=" + URLEncoder.encode("json", StandardCharsets.UTF_8) +
                 "&" + URLEncoder.encode("api_paste_name", StandardCharsets.UTF_8) + "=" + URLEncoder.encode("Multiverse-Core Debug Info", StandardCharsets.UTF_8);
     }
 

src/main/java/org/mvplugins/multiverse/core/utils/webpaste/PastesDevPasteService.java

@@ -39,8 +39,9 @@ final class PastesDevPasteService extends PasteService {
     @Override
     public String postData(String data) throws PasteFailedException {
         try {
-            String stringJSON = this.exec(encodeData(data), ContentType.PLAINTEXT_YAML);
-            return "https://pastes.dev/" + ((JSONObject) new JSONParser(JSONParser.DEFAULT_PERMISSIVE_MODE).parse(stringJSON)).get("key");
+            String stringJSON = this.exec(encodeData(data), ContentType.JSON);
+            return DUMPS_VIEWER_URL +
+                    ((JSONObject) new JSONParser(JSONParser.DEFAULT_PERMISSIVE_MODE).parse(stringJSON)).get("key");
         } catch (IOException | ParseException e) {
             throw new PasteFailedException(e);
         }

src/main/java/org/mvplugins/multiverse/core/world/LoadedMultiverseWorld.java

@@ -39,7 +39,7 @@ public final class LoadedMultiverseWorld extends MultiverseWorld {
             @NotNull LocationManipulation locationManipulation,
             @NotNull EntityPurger entityPurger
     ) {
-        super(world.getName(), worldConfig, config);
+        super(worldConfig, config);
         this.worldUid = world.getUID();
         this.blockSafety = blockSafety;
         this.locationManipulation = locationManipulation;
@@ -77,7 +77,7 @@ public final class LoadedMultiverseWorld extends MultiverseWorld {
             Logging.fine("Spawn location from world.dat file was unsafe!!");
             Logging.fine("NOT adjusting spawn for '" + this.getAliasOrName() + "' because you told me not to.");
             Logging.fine("To turn on spawn adjustment for this world simply type:");
-            Logging.fine("/mvm set adjustspawn true " + this.getAliasOrName());
+            Logging.fine("/mv modify %s set adjust-spawn true", getName());
             return location;
         }
 
@@ -173,7 +173,7 @@ public final class LoadedMultiverseWorld extends MultiverseWorld {
      * {@inheritDoc}
      */
     @Override
-    void setWorldConfig(WorldConfig worldConfig) {
+    void setWorldConfig(@NotNull WorldConfig worldConfig) {
         super.setWorldConfig(worldConfig);
         setupWorldConfig(getBukkitWorld().get());
     }
@@ -184,7 +184,8 @@ public final class LoadedMultiverseWorld extends MultiverseWorld {
     @Override
     public String toString() {
         return "LoadedMultiverseWorld{"
-                + "name='" + worldName + "', "
+                + "key='" + getKey() + "', "
+                + "name='" + getName() + "', "
                 + "env='" + getEnvironment() + "', "
                 + "type='" + getWorldType().getOrNull() + "', "
                 + "gen='" + getGenerator() + "'"

src/main/java/org/mvplugins/multiverse/core/world/MultiverseWorld.java

@@ -1,21 +1,29 @@
 package org.mvplugins.multiverse.core.world;
 
+import java.io.File;
+import java.util.Collections;
 import java.util.List;
+import java.util.Map;
 
 import com.google.common.base.Strings;
+import io.vavr.control.Option;
 import io.vavr.control.Try;
 import org.bukkit.Bukkit;
 import org.bukkit.Difficulty;
 import org.bukkit.GameMode;
 import org.bukkit.Location;
 import org.bukkit.Material;
+import org.bukkit.NamespacedKey;
 import org.bukkit.World;
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
+import org.jetbrains.annotations.UnmodifiableView;
 import org.mvplugins.multiverse.core.config.CoreConfig;
 import org.mvplugins.multiverse.core.config.handle.StringPropertyHandle;
 import org.mvplugins.multiverse.core.utils.text.ChatTextFormatter;
+import org.mvplugins.multiverse.core.world.helpers.WorldFolderResolver;
 import org.mvplugins.multiverse.core.world.location.SpawnLocation;
 import org.mvplugins.multiverse.core.world.entity.EntitySpawnConfig;
 
@@ -23,11 +31,6 @@ import org.mvplugins.multiverse.core.world.entity.EntitySpawnConfig;
  * Represents a world handled by Multiverse which has all the custom properties provided by Multiverse.
  */
 public sealed class MultiverseWorld permits LoadedMultiverseWorld {
-    /**
-     * This world's name.
-     */
-    protected final String worldName;
-
     /**
      * This world's configuration.
      */
@@ -36,8 +39,7 @@ public sealed class MultiverseWorld permits LoadedMultiverseWorld {
     protected final CoreConfig config;
     private String colourlessAlias = "";
 
-    MultiverseWorld(String worldName, WorldConfig worldConfig, CoreConfig config) {
-        this.worldName = worldName;
+    MultiverseWorld(WorldConfig worldConfig, CoreConfig config) {
         this.worldConfig = worldConfig;
         this.config = config;
         this.worldConfig.setMVWorld(this);
@@ -45,15 +47,46 @@ public sealed class MultiverseWorld permits LoadedMultiverseWorld {
     }
 
     /**
-     * Gets the name of this world. The name cannot be changed.
+     * The key that represents this world. This should now be used as the unique key for the world instead
+     * of the world name. Also note that the key cannot be modified.
+     *
+     * @return The world key
+     */
+    @ApiStatus.AvailableSince("5.7")
+    @NotNull
+    public NamespacedKey getKey() {
+        return worldConfig.getWorldKeyOrName().usableKey();
+    }
+
+    /**
+     * Gets the name of this world. Prefer to use {@link #getKey()} as unique id instead of this name.
+     * Also note that the name cannot be modified.
      * <br/>
-     * Note for plugin developers: Usually {@link #getAliasOrName()}
-     * is what you want to use instead of this method.
+     * Note for plugin developers: Usually {@link #getAliasOrName()}is what you want to use instead of this method.
      *
      * @return The name of the world as a String.
      */
+    @NotNull
     public String getName() {
-        return worldName;
+        return worldConfig.getLegacyWorldName();
+    }
+
+    /**
+     * Gets the folder where all the world contents are stored in. Generally, the location of the folder is at the server
+     * roots directory for pre-26.1 servers, and at "[level]/dimensions" folder under the world level directory for
+     * 26.1+ PaperMC servers.
+     * <br />
+     * Note this folder location is based on Multiverse's understanding of Paper and Spigot's folder structure. If the
+     * server software does something weird, this folder will not reflect the actual world folder location.
+     * <br />
+     * If the world is loaded, you should use {@link World#getWorldFolder()} instead as it is more accurate.
+     * This method is more of a fallback for when the world is not loaded.
+     *
+     * @return The world folder.
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public File getOfflineWorldFolder() {
+        return WorldFolderResolver.resolve(this);
     }
 
     /**
@@ -66,7 +99,8 @@ public sealed class MultiverseWorld permits LoadedMultiverseWorld {
     }
 
     /**
-     * Gets whether this world is loaded.
+     * Gets whether this world is loaded. Note that this may return false even if this is a stored instance of
+     * {@link LoadedMultiverseWorld} as worlds can be unloaded anytime.
      *
      * @return True if the world is loaded, else false.
      */
@@ -74,6 +108,23 @@ public sealed class MultiverseWorld permits LoadedMultiverseWorld {
         return worldConfig.isLoadedWorld();
     }
 
+    /**
+     * Attempts to get loaded world instance. Only returns a value if the world is loaded at the time of calling, even
+     * if this is a stored instance of {@link LoadedMultiverseWorld}.
+     * <br/>
+     * You may use {@link #isLoaded()} to check if the world is loaded first.
+     *
+     * @return Loaded world instance wrapped in an Option, or None if the world is not loaded.
+     *
+     * @since 5.5
+     */
+    @ApiStatus.AvailableSince("5.5")
+    public Option<LoadedMultiverseWorld> asLoadedWorld() {
+        return Option.of(worldConfig.getMVWorld())
+                .filter(world -> world instanceof LoadedMultiverseWorld)
+                .map(world -> (LoadedMultiverseWorld) world);
+    }
+
     /**
      * Gets the properties handler of this world.
      *
@@ -124,7 +175,7 @@ public sealed class MultiverseWorld permits LoadedMultiverseWorld {
      * @return The alias of the world as a String.
      */
     public String getAliasOrName() {
-        return Strings.isNullOrEmpty(worldConfig.getAlias()) ? worldName : worldConfig.getAlias();
+        return Strings.isNullOrEmpty(worldConfig.getAlias()) ? getName() : worldConfig.getAlias();
     }
 
     /**
@@ -373,6 +424,19 @@ public sealed class MultiverseWorld permits LoadedMultiverseWorld {
         return worldConfig.getGenerator();
     }
 
+    /**
+     * Gets the generator settings used to create this world. You cannot change this after world creation.
+     * Changing this manually in config on existing world will have no effect on the world generation.
+     *
+     * @return The generator settings string.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public String getGeneratorSettings() {
+        return worldConfig.getGeneratorSettings();
+    }
+
     /**
      * Gets whether or not this world will display in chat, mvw and mvl regardless if a user has the
      * access permissions to go to this world.
@@ -434,6 +498,59 @@ public sealed class MultiverseWorld permits LoadedMultiverseWorld {
         return worldConfig.setKeepSpawnInMemory(keepSpawnInMemory);
     }
 
+    /**
+     * Get all meta key-value pairs for this world. This is an unmodifiable view of the internal map, so changes to
+     * the world meta will be reflected in this map, but attempts to modify this map will throw an exception.
+     *
+     * @return An unmodifiable view of all meta key-value pairs for this world.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public @UnmodifiableView Map<String, String> getAllMeta() {
+        return Collections.unmodifiableMap(worldConfig.getMeta());
+    }
+
+    /**
+     * Gets the meta value for the given key if it exists.
+     *
+     * @param key The meta key to look up, may be {@code null} in which case an empty result is returned.
+     * @return An {@link Option} containing the meta value if present, otherwise an empty {@link Option}.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public @NotNull Option<String> getMeta(@Nullable String key) {
+        return Option.of(worldConfig.getMeta().get(key));
+    }
+
+    /**
+     * Sets a meta key-value pair for this world. Existing value for the key will be replaced.
+     *
+     * @param key The meta key to set, must not be {@code null}.
+     * @param value The meta value to set.
+     * @return Result of setting the property.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public @NotNull Try<Void> setMeta(@NotNull String key, @Nullable String value) {
+        return worldConfig.setMeta(key, value);
+    }
+
+    /**
+     * Removes the meta entry associated with the given key.
+     *
+     * @param key The meta key to remove.
+     * @return Result of removing the property.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public @NotNull Try<Void> removeMeta(@NotNull String key) {
+        return worldConfig.removeMeta(key);
+    }
+
     /**
      * Gets the player limit for this world after which players without an override
      * permission node will not be allowed in. A value of -1 or less signifies no limit
@@ -669,7 +786,7 @@ public sealed class MultiverseWorld permits LoadedMultiverseWorld {
      *
      * @return The world config.
      */
-    WorldConfig getWorldConfig() {
+    @NotNull WorldConfig getWorldConfig() {
         return worldConfig;
     }
 
@@ -678,7 +795,7 @@ public sealed class MultiverseWorld permits LoadedMultiverseWorld {
      *
      * @param worldConfig   The world config.
      */
-    void setWorldConfig(WorldConfig worldConfig) {
+    void setWorldConfig(@NotNull WorldConfig worldConfig) {
         this.worldConfig = worldConfig;
     }
 
@@ -688,7 +805,8 @@ public sealed class MultiverseWorld permits LoadedMultiverseWorld {
     @Override
     public String toString() {
         return "MultiverseWorld{"
-                + "name='" + worldName + "', "
+                + "key='" + getKey() + "', "
+                + "name='" + getName() + "', "
                 + "env='" + getEnvironment() + "', "
                 + "gen='" + getGenerator() + "'"
                 + '}';

src/main/java/org/mvplugins/multiverse/core/world/NewAndRemovedWorlds.java

@@ -1,5 +1,7 @@
 package org.mvplugins.multiverse.core.world;
 
+import org.mvplugins.multiverse.core.world.key.WorldKeyOrName;
+
 import java.util.List;
 
 /**
@@ -8,5 +10,5 @@ import java.util.List;
  * @param newWorlds     List of the new WorldConfigs added
  * @param removedWorlds List of the worlds removed from the config
  */
-record NewAndRemovedWorlds(List<WorldConfig> newWorlds, List<String> removedWorlds) {
+record NewAndRemovedWorlds(List<WorldConfig> newWorlds, List<WorldKeyOrName> removedWorlds) {
 }

src/main/java/org/mvplugins/multiverse/core/world/WorldConfig.java

@@ -2,6 +2,7 @@ package org.mvplugins.multiverse.core.world;
 
 import java.util.List;
 import java.util.Locale;
+import java.util.Map;
 import java.util.concurrent.atomic.AtomicReference;
 
 import com.dumptruckman.minecraft.util.Logging;
@@ -29,6 +30,7 @@ import org.mvplugins.multiverse.core.config.migration.action.MoveMigratorAction;
 import org.mvplugins.multiverse.core.config.migration.action.NullStringMigratorAction;
 import org.mvplugins.multiverse.core.config.migration.VersionMigrator;
 import org.mvplugins.multiverse.core.economy.MVEconomist;
+import org.mvplugins.multiverse.core.world.key.WorldKeyOrName;
 import org.mvplugins.multiverse.core.world.location.SpawnLocation;
 import org.mvplugins.multiverse.core.world.entity.EntitySpawnConfig;
 
@@ -37,16 +39,16 @@ import org.mvplugins.multiverse.core.world.entity.EntitySpawnConfig;
  */
 final class WorldConfig {
 
-    private final String worldName;
+    private final WorldKeyOrName keyOrName;
     private final WorldConfigNodes configNodes;
     private final MemoryConfigurationHandle configHandle;
     private final StringPropertyHandle stringPropertyHandle;
 
     WorldConfig(
-            @NotNull String worldName,
+            @NotNull WorldKeyOrName keyOrName,
             @NotNull ConfigurationSection configSection,
             @NotNull MultiverseCore multiverseCore) {
-        this.worldName = worldName;
+        this.keyOrName = keyOrName;
         this.configNodes = new WorldConfigNodes(multiverseCore);
         this.configHandle = MemoryConfigurationHandle.builder(configSection, configNodes.getNodes())
                 .logger(Logging.getLogger())
@@ -118,6 +120,11 @@ final class WorldConfig {
                         .addAction(MoveMigratorAction.of("spawning.animals", "spawning.animal"))
                         .addAction(MoveMigratorAction.of("spawning.monsters", "spawning.monster"))
                         .build())
+                .addVersionMigrator(VersionMigrator.builder(1.3)
+                        .addAction(config -> config.set("read-only.legacy-world-name", keyOrName.usableName()))
+                        .addAction(MoveMigratorAction.of("environment", "read-only.environment"))
+                        .addAction(MoveMigratorAction.of("seed", "read-only.seed"))
+                        .build())
                 .build();
     }
 
@@ -132,7 +139,7 @@ final class WorldConfig {
     Try<Void> save() {
         return configHandle.save().onFailure(ex ->
                 Logging.warning("Failed to save world config for world '%s'. %s",
-                        worldName, ex.getLocalizedMessage()));
+                        keyOrName, ex.getLocalizedMessage()));
     }
 
     ConfigurationSection getConfigurationSection() {
@@ -143,8 +150,8 @@ final class WorldConfig {
         return stringPropertyHandle;
     }
 
-    String getWorldName() {
-        return worldName;
+    WorldKeyOrName getWorldKeyOrName() {
+        return keyOrName;
     }
 
     boolean getAdjustSpawn() {
@@ -258,14 +265,6 @@ final class WorldConfig {
         return configHandle.set(configNodes.entryFeeCurrency, entryFeeCurrency);
     }
 
-    World.Environment getEnvironment() {
-        return configHandle.get(configNodes.environment);
-    }
-
-    Try<Void> setEnvironment(World.Environment environment) {
-        return configHandle.set(configNodes.environment, environment);
-    }
-
     GameMode getGameMode() {
         return configHandle.get(configNodes.gamemode);
     }
@@ -305,6 +304,18 @@ final class WorldConfig {
         return configHandle.set(configNodes.keepSpawnInMemory, keepSpawnInMemory);
     }
 
+    Map<String, String> getMeta() {
+        return configHandle.get(configNodes.meta);
+    }
+
+    Try<Void> setMeta(String key, String value) {
+        return configHandle.set(configNodes.meta, key, value);
+    }
+
+    Try<Void> removeMeta(String key) {
+        return configHandle.remove(configNodes.meta, key);
+    }
+
     int getPlayerLimit() {
         return configHandle.get(configNodes.playerLimit);
     }
@@ -345,14 +356,6 @@ final class WorldConfig {
         return configHandle.set(configNodes.scale, scale);
     }
 
-    long getSeed() {
-        return configHandle.get(configNodes.seed);
-    }
-
-    Try<Void> setSeed(long seed) {
-        return configHandle.set(configNodes.seed, seed);
-    }
-
     SpawnLocation getSpawnLocation() {
         return configHandle.get(configNodes.spawnLocation);
     }
@@ -377,10 +380,46 @@ final class WorldConfig {
         return configHandle.set(configNodes.worldBlacklist, worldBlacklist);
     }
 
+    World.Environment getEnvironment() {
+        return configHandle.get(configNodes.environment);
+    }
+
+    Try<Void> setEnvironment(World.Environment environment) {
+        return configHandle.set(configNodes.environment, environment);
+    }
+
+    String getGeneratorSettings() {
+        return configHandle.get(configNodes.generatorSettings);
+    }
+
+    Try<Void> setGeneratorSettings(String generatorSettings) {
+        return configHandle.set(configNodes.generatorSettings, generatorSettings);
+    }
+
+    String getLegacyWorldName() {
+        return configHandle.get(configNodes.legacyWorldName);
+    }
+
+    Try<Void> setLegacyWorldName(String legacyWorldName) {
+        return configHandle.set(configNodes.legacyWorldName, legacyWorldName);
+    }
+
+    long getSeed() {
+        return configHandle.get(configNodes.seed);
+    }
+
+    Try<Void> setSeed(long seed) {
+        return configHandle.set(configNodes.seed, seed);
+    }
+
     void setMVWorld(@NotNull MultiverseWorld world) {
         configNodes.setWorld(world);
     }
 
+    MultiverseWorld getMVWorld() {
+        return configNodes.getWorld();
+    }
+
     boolean isLoadedWorld() {
         return configNodes.getWorld() instanceof LoadedMultiverseWorld;
     }
@@ -392,7 +431,7 @@ final class WorldConfig {
     /**
      * Migrates the entry fee settings. Assumes entry fee is disabled if currency is not set.
      */
-    static final class EntryFeeMigrator implements MigratorAction {
+    private static final class EntryFeeMigrator implements MigratorAction {
         @Override
         public void migrate(ConfigurationSection config) {
             String currency = config.getString("entry-fee.currency", "");

src/main/java/org/mvplugins/multiverse/core/world/WorldConfigNodes.java

@@ -7,6 +7,7 @@ import java.util.Objects;
 import com.dumptruckman.minecraft.util.Logging;
 import io.vavr.control.Option;
 import org.bukkit.Bukkit;
+import org.bukkit.ChatColor;
 import org.bukkit.Difficulty;
 import org.bukkit.GameMode;
 import org.bukkit.Material;
@@ -17,6 +18,7 @@ import org.jetbrains.annotations.NotNull;
 
 import org.mvplugins.multiverse.core.MultiverseCore;
 import org.mvplugins.multiverse.core.config.CoreConfig;
+import org.mvplugins.multiverse.core.config.node.MapConfigNode;
 import org.mvplugins.multiverse.core.config.node.serializer.NodeSerializer;
 import org.mvplugins.multiverse.core.event.world.MVWorldPropertyChangedEvent;
 import org.mvplugins.multiverse.core.config.node.ConfigNode;
@@ -24,6 +26,7 @@ import org.mvplugins.multiverse.core.config.node.ListConfigNode;
 import org.mvplugins.multiverse.core.config.node.NodeGroup;
 import org.mvplugins.multiverse.core.economy.MVEconomist;
 import org.mvplugins.multiverse.core.utils.MaterialConverter;
+import org.mvplugins.multiverse.core.utils.text.ChatTextFormatter;
 import org.mvplugins.multiverse.core.world.helpers.EnforcementHandler;
 import org.mvplugins.multiverse.core.world.location.NullSpawnLocation;
 import org.mvplugins.multiverse.core.world.location.SpawnLocation;
@@ -90,6 +93,8 @@ final class WorldConfigNodes {
             .onLoadAndChange((oldValue, newValue) -> {
                 if (world == null) return;
                 world.updateColourlessAlias();
+                worldManager.getWorldStore().changeAlias(
+                        ChatTextFormatter.removeColor(oldValue), ChatTextFormatter.removeColor(newValue), world);
             }));
 
     final ConfigNode<Boolean> allowAdvancementGrant = node(ConfigNode.builder("allow-advancement-grant", Boolean.class)
@@ -172,11 +177,6 @@ final class WorldConfigNodes {
                 }
             }));
 
-    final ConfigNode<World.Environment> environment = node(ConfigNode
-            .builder("environment", World.Environment.class)
-            .defaultValue(World.Environment.NORMAL)
-            .hidden());
-
     final ConfigNode<GameMode> gamemode = node(ConfigNode.builder("gamemode", GameMode.class)
             .defaultValue(GameMode.SURVIVAL)
             .onLoadAndChange((oldValue, newValue) -> {
@@ -198,11 +198,21 @@ final class WorldConfigNodes {
     final ConfigNode<Boolean> keepSpawnInMemory = node(ConfigNode
             .builder("keep-spawn-in-memory", Boolean.class)
             .defaultValue(true)
-            .onLoadAndChange((oldValue, newValue) -> {
+            .onLoadAndChange((sender, oldValue, newValue) -> {
                 if (!(world instanceof LoadedMultiverseWorld loadedWorld)) return;
-                loadedWorld.getBukkitWorld().peek(bukkitWorld -> bukkitWorld.setKeepSpawnInMemory(newValue));
+                loadedWorld.getBukkitWorld().peek(bukkitWorld -> {
+                    bukkitWorld.setKeepSpawnInMemory(newValue);
+                    if (bukkitWorld.getKeepSpawnInMemory() != newValue) {
+                        sender.sendMessage(ChatColor.RED + "Keep spawn in memory feature has been removed by " +
+                                "Minecraft in 1.21.9+ and will no longer have any effect when set to true.");
+                    }
+                });
             }));
 
+    final MapConfigNode<String, String> meta = (MapConfigNode<String, String>) node(MapConfigNode
+            .mapBuilder("meta", String.class, String.class)
+            .hidden());
+
     final ConfigNode<Integer> playerLimit = node(ConfigNode.builder("player-limit", Integer.class)
             .defaultValue(-1));
 
@@ -234,10 +244,6 @@ final class WorldConfigNodes {
                 };
             }));
 
-    final ConfigNode<Long> seed = node(ConfigNode.builder("seed", Long.class)
-            .defaultValue(Long.MIN_VALUE)
-            .hidden());
-
     final ConfigNode<SpawnLocation> spawnLocation = node(ConfigNode.builder("spawn-location", SpawnLocation.class)
             .defaultValue(NullSpawnLocation.get())
             .hidden()
@@ -274,6 +280,22 @@ final class WorldConfigNodes {
 
     final ConfigNode<List<String>> worldBlacklist = node(ListConfigNode.listBuilder("world-blacklist", String.class));
 
+    final ConfigNode<World.Environment> environment = node(ConfigNode
+            .builder("read-only.environment", World.Environment.class)
+            .defaultValue(World.Environment.NORMAL)
+            .hidden());
+
+    final ConfigNode<String> generatorSettings = node(ConfigNode.builder("read-only.generator-settings", String.class)
+            .defaultValue("")
+            .hidden());
+
+    final ConfigNode<String> legacyWorldName = node(ConfigNode.builder("read-only.legacy-world-name", String.class)
+            .hidden());
+
+    final ConfigNode<Long> seed = node(ConfigNode.builder("read-only.seed", Long.class)
+            .defaultValue(Long.MIN_VALUE)
+            .hidden());
+
     final ConfigNode<Double> version = node(ConfigNode.builder("version", Double.class)
             .defaultValue(CONFIG_VERSION)
             .hidden());

src/main/java/org/mvplugins/multiverse/core/world/WorldManager.java

@@ -1,14 +1,10 @@
 package org.mvplugins.multiverse.core.world;
 
 import java.io.File;
-import java.lang.reflect.Method;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
-import java.util.Collections;
-import java.util.HashMap;
 import java.util.List;
-import java.util.Locale;
 import java.util.Map;
 import java.util.Objects;
 import java.util.concurrent.atomic.AtomicReference;
@@ -17,19 +13,22 @@ import java.util.stream.Collectors;
 
 import com.dumptruckman.minecraft.util.Logging;
 import com.google.common.base.Strings;
-import io.papermc.lib.PaperLib;
 import io.vavr.control.Option;
 import io.vavr.control.Try;
 import jakarta.inject.Inject;
+import jakarta.inject.Provider;
 import org.bukkit.Bukkit;
+import org.bukkit.GameRule;
 import org.bukkit.Location;
 import org.bukkit.World;
+import org.bukkit.WorldBorder;
 import org.bukkit.WorldCreator;
 import org.bukkit.WorldType;
 import org.bukkit.plugin.PluginManager;
 import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
+import org.jetbrains.annotations.Unmodifiable;
 import org.jvnet.hk2.annotations.Service;
 
 import org.mvplugins.multiverse.core.config.CoreConfig;
@@ -48,19 +47,23 @@ import org.mvplugins.multiverse.core.locale.message.MessageReplacement.Replace;
 import org.mvplugins.multiverse.core.permissions.CorePermissions;
 import org.mvplugins.multiverse.core.teleportation.BlockSafety;
 import org.mvplugins.multiverse.core.teleportation.LocationManipulation;
-import org.mvplugins.multiverse.core.utils.ReflectHelper;
 import org.mvplugins.multiverse.core.utils.ServerProperties;
+import org.mvplugins.multiverse.core.utils.compatibility.BukkitCompatibility;
+import org.mvplugins.multiverse.core.utils.compatibility.WorldCompatibility;
+import org.mvplugins.multiverse.core.utils.compatibility.WorldCreatorCompatibility;
 import org.mvplugins.multiverse.core.utils.result.Attempt;
 import org.mvplugins.multiverse.core.utils.result.FailureReason;
 import org.mvplugins.multiverse.core.utils.FileUtils;
-import org.mvplugins.multiverse.core.utils.text.ChatTextFormatter;
 import org.mvplugins.multiverse.core.world.biomeprovider.BiomeProviderFactory;
 import org.mvplugins.multiverse.core.world.entity.EntityPurger;
 import org.mvplugins.multiverse.core.world.generators.GeneratorProvider;
 import org.mvplugins.multiverse.core.world.helpers.DataStore.GameRulesStore;
 import org.mvplugins.multiverse.core.world.helpers.DataTransfer;
-import org.mvplugins.multiverse.core.world.helpers.DimensionFinder.DimensionFormat;
+import org.mvplugins.multiverse.core.world.helpers.DimensionFinder;
+import org.mvplugins.multiverse.core.world.helpers.PotentialWorldFinder;
+import org.mvplugins.multiverse.core.world.helpers.WorldFolderResolver;
 import org.mvplugins.multiverse.core.world.helpers.WorldNameChecker;
+import org.mvplugins.multiverse.core.world.key.WorldKeyOrName;
 import org.mvplugins.multiverse.core.world.options.CloneWorldOptions;
 import org.mvplugins.multiverse.core.world.options.CreateWorldOptions;
 import org.mvplugins.multiverse.core.world.options.DeleteWorldOptions;
@@ -87,12 +90,12 @@ import static org.mvplugins.multiverse.core.world.helpers.DataStore.WorldConfigS
 @Service // SUPPRESS CHECKSTYLE: ClassFanOutComplexity This is the world manager, it's going to be complex.
 public final class WorldManager {
 
-    private static final List<String> CLONE_IGNORE_FILES = Arrays.asList("uid.dat", "session.lock");
-    private static final DimensionFormat DEFAULT_NETHER_FORMAT = new DimensionFormat("%overworld%_nether");
-    private static final DimensionFormat DEFAULT_END_FORMAT = new DimensionFormat("%overworld%_the_end");
+    private static final List<String> CLONE_IGNORE_FILES = List.of(
+            "uid.dat", "session.lock", // All pre 26.1 format
+            "data/paper/metadata.dat"  // New papermc format for 26.1+
+    );
 
-    private final Map<String, MultiverseWorld> worldsMap;
-    private final Map<String, LoadedMultiverseWorld> loadedWorldsMap;
+    private final WorldStore worldStore;
     private final List<String> unloadTracker;
     private final List<String> loadTracker;
     private final WorldsConfigManager worldsConfigManager;
@@ -107,9 +110,11 @@ public final class WorldManager {
     private final ServerProperties serverProperties;
     private final CoreConfig config;
     private final EntityPurger entityPurger;
+    private final Provider<PotentialWorldFinder> potentialWorldFinder;
 
     @Inject
     WorldManager(
+            @NotNull WorldStore worldStore,
             @NotNull WorldsConfigManager worldsConfigManager,
             @NotNull WorldNameChecker worldNameChecker,
             @NotNull BiomeProviderFactory biomeProviderFactory,
@@ -121,7 +126,9 @@ public final class WorldManager {
             @NotNull CorePermissions corePermissions,
             @NotNull ServerProperties serverProperties,
             @NotNull CoreConfig config,
-            @NotNull EntityPurger entityPurger) {
+            @NotNull EntityPurger entityPurger,
+            @NotNull Provider<PotentialWorldFinder> potentialWorldFinder) {
+        this.worldStore = worldStore;
         this.worldsConfigManager = worldsConfigManager;
         this.worldNameChecker = worldNameChecker;
         this.biomeProviderFactory = biomeProviderFactory;
@@ -134,9 +141,8 @@ public final class WorldManager {
         this.serverProperties = serverProperties;
         this.config = config;
         this.entityPurger = entityPurger;
+        this.potentialWorldFinder = potentialWorldFinder;
 
-        this.worldsMap = new HashMap<>();
-        this.loadedWorldsMap = new HashMap<>();
         this.unloadTracker = new ArrayList<>();
         this.loadTracker = new ArrayList<>();
     }
@@ -168,19 +174,23 @@ public final class WorldManager {
     }
 
     private void loadNewWorldConfigs(Collection<WorldConfig> newWorldConfigs) {
-        newWorldConfigs.forEach(worldConfig -> Option.of(worldsMap.get(worldConfig.getWorldName()))
-                .peek(unloadedWorld ->  unloadedWorld.setWorldConfig(worldConfig))
-                .onEmpty(() -> newMultiverseWorld(worldConfig.getWorldName(), worldConfig)));
+        newWorldConfigs.forEach(worldConfig -> {
+            worldStore.getUnloadedWorldRef(worldConfig.getWorldKeyOrName().usableName())
+                    .peek(unloadedWorld -> unloadedWorld.setWorldConfig(worldConfig))
+                    .onEmpty(() -> newMultiverseWorld(worldConfig));
+            worldStore.getLoadedWorld(worldConfig.getWorldKeyOrName().usableName())
+                    .peek(loadedWorld -> loadedWorld.setWorldConfig(worldConfig));
+        });
     }
 
-    private void removeWorldsNotInConfigs(Collection<String> removedWorlds) {
-        removedWorlds.forEach(worldName -> getWorld(worldName)
+    private void removeWorldsNotInConfigs(Collection<WorldKeyOrName> removedWorlds) {
+        removedWorlds.forEach(keyOrName -> getWorld(keyOrName.usableName())
                 .map(world -> removeWorld(RemoveWorldOptions.world(world)))
-                .getOrElse(() -> worldActionResult(RemoveFailureReason.WORLD_NON_EXISTENT, worldName))
+                .getOrElse(() -> worldActionResult(RemoveFailureReason.WORLD_NON_EXISTENT, keyOrName.toString()))
                 .onFailure(failure ->
-                        Logging.severe("Failed to unload world %s: %s", worldName, failure))
+                        Logging.severe("Failed to unload world %s: %s", keyOrName, failure))
                 .onSuccess(success ->
-                        Logging.fine("Unloaded world %s as it was removed from config", worldName)));
+                        Logging.fine("Unloaded world %s as it was removed from config", keyOrName)));
     }
 
     /**
@@ -192,9 +202,10 @@ public final class WorldManager {
                 .collect(Collectors.toMap(World::getName, Function.identity()));
 
         serverProperties.getLevelName().peek(overworldName -> {
+            //TODO: check by namespaced key instead
             World overworld = bukkitWorlds.remove(overworldName);
-            World nether = bukkitWorlds.remove(DEFAULT_NETHER_FORMAT.replaceOverworld(overworldName));
-            World end = bukkitWorlds.remove(DEFAULT_END_FORMAT.replaceOverworld(overworldName));
+            World nether = bukkitWorlds.remove(DimensionFinder.DEFAULT_NETHER_FORMAT.replaceOverworld(overworldName));
+            World end = bukkitWorlds.remove(DimensionFinder.DEFAULT_END_FORMAT.replaceOverworld(overworldName));
 
             if (config.getAutoImportDefaultWorlds()) {
                 importExistingBukkitWorld(overworld);
@@ -241,43 +252,60 @@ public final class WorldManager {
      * @return The result of the creation.
      */
     public Attempt<LoadedMultiverseWorld, CreateFailureReason> createWorld(CreateWorldOptions options) {
-        return validateCreateWorldOptions(options).mapAttempt(this::doCreateWorld);
+        return parseCreateWorldOptionsKeyOrName(options).mapAttempt(this::doCreateWorld);
     }
 
-    private Attempt<CreateWorldOptions, CreateFailureReason> validateCreateWorldOptions(
+    private Attempt<KeyOrNameWithOptions<CreateWorldOptions>, CreateFailureReason> parseCreateWorldOptionsKeyOrName(
             CreateWorldOptions options) {
-        if (!worldNameChecker.isValidWorldName(options.worldName())) {
-            return worldActionResult(CreateFailureReason.INVALID_WORLDNAME, options.worldName());
-        } else if (getLoadedWorld(options.worldName()).isDefined()) {
-            return worldActionResult(CreateFailureReason.WORLD_EXIST_LOADED, options.worldName());
-        } else if (getWorld(options.worldName()).isDefined()) {
-            return worldActionResult(CreateFailureReason.WORLD_EXIST_UNLOADED, options.worldName());
-        } else if (options.doFolderCheck() && worldNameChecker.hasWorldFolder(options.worldName())) {
-            return worldActionResult(CreateFailureReason.WORLD_EXIST_FOLDER, options.worldName());
-        }
-        return worldActionResult(options);
+        return options.keyOrName()
+                .fold(WorldKeyOrName::parse, Attempt::success)
+                .transform(CreateFailureReason.INVALID_WORLDNAME)
+                .failIf(keyOrName -> !worldNameChecker.isValidWorldName(keyOrName.usableName()),
+                        keyOrName -> worldActionResult(CreateFailureReason.INVALID_WORLDNAME, keyOrName))
+                .failIf(keyOrName -> keyOrName.isKey() && !WorldCreatorCompatibility.canCreateWorldWithKey(),
+                        keyOrName -> worldActionResult(CreateFailureReason.NAMESPACEDKEY_UNSUPPORTED, keyOrName))
+                .failIf(worldStore::isLoadedWorld,
+                        keyOrName -> worldActionResult(CreateFailureReason.WORLD_EXIST_LOADED, keyOrName))
+                .failIf(worldStore::isUnloadedWorld,
+                        keyOrName -> worldActionResult(CreateFailureReason.WORLD_EXIST_UNLOADED, keyOrName))
+                .failIf(keyOrName -> options.doFolderCheck() && worldNameChecker.hasWorldFolder(keyOrName),
+                        keyOrName -> worldActionResult(CreateFailureReason.WORLD_EXIST_FOLDER, keyOrName))
+                .map(keyOrName -> new KeyOrNameWithOptions<>(keyOrName, options));
     }
 
     private Attempt<LoadedMultiverseWorld, CreateFailureReason> doCreateWorld(
-            CreateWorldOptions options) {
-        String generatorString = generatorProvider.parseGeneratorString(options.worldName(), options.generator());
-        WorldCreator worldCreator = WorldCreator.name(options.worldName())
+            KeyOrNameWithOptions<CreateWorldOptions> keyOrNameWithOptions) {
+        WorldKeyOrName keyOrName = keyOrNameWithOptions.keyOrName();
+        CreateWorldOptions options = keyOrNameWithOptions.options();
+        String generatorString = generatorProvider.parseGeneratorString(keyOrName.usableName(), options.generator());
+        WorldCreator worldCreator = WorldCreatorCompatibility.ofKeyOrName(keyOrName)
                 .environment(options.environment())
                 .generateStructures(options.generateStructures())
                 .generatorSettings(options.generatorSettings())
                 .seed(options.seed())
                 .type(options.worldType());
-
-        return addBiomeProviderToCreator(worldCreator, options.worldName(), options.biome())
+        WorldCreatorCompatibility.setBonusChest(worldCreator, options.bonusChest());
+        options.forcedSpawnPosition().peek(position -> WorldCreatorCompatibility.setForcedSpawnPosition(worldCreator, position));
+        return addBiomeProviderToCreator(worldCreator, keyOrName.usableName(), options.biome())
                 .mapAttempt(creator -> addGeneratorToCreator(creator, generatorString))
                 .mapAttempt(this::createBukkitWorld)
                 .transform(CreateFailureReason.WORLD_CREATOR_FAILED)
                 .map(bukkitWorld -> newLoadedMultiverseWorld(
-                            bukkitWorld,
-                            generatorString,
-                            options.biome(),
-                            options.useSpawnAdjust()))
-                .peek(loadedWorld -> pluginManager.callEvent(new MVWorldCreatedEvent(loadedWorld)));
+                        bukkitWorld,
+                        generatorString,
+                        options.biome(),
+                        options.generatorSettings(),
+                        options.useSpawnAdjust()))
+                .peek(loadedWorld -> postCreateWorld(loadedWorld, options));
+    }
+
+    private void postCreateWorld(LoadedMultiverseWorld loadedWorld, CreateWorldOptions options) {
+        options.worldPropertyStrings().forEach((key, value) -> loadedWorld.getStringPropertyHandle()
+                .setPropertyString(key, value)
+                .onFailure(failure -> Logging.warning("Failed to set property '%s' to '%s' for world %s: %s",
+                        key, value, loadedWorld.getName(), failure.getMessage())));
+        pluginManager.callEvent(new MVWorldCreatedEvent(loadedWorld));
+        saveWorldsConfig();
     }
 
     /**
@@ -287,34 +315,51 @@ public final class WorldManager {
      * @return The result of the import.
      */
     public Attempt<LoadedMultiverseWorld, ImportFailureReason> importWorld(ImportWorldOptions options) {
-        String worldName = options.worldName();
-        if (isLoadedWorld(worldName)) {
-            return worldActionResult(ImportFailureReason.WORLD_EXIST_LOADED, worldName);
-        } else if (isWorld(worldName)) {
-            return worldActionResult(ImportFailureReason.WORLD_EXIST_UNLOADED, worldName);
-        }
-        return Option.of(Bukkit.getWorld(worldName))
-                .map(bukkitWorld -> doImportBukkitWorld(options, bukkitWorld))
-                .getOrElse(() -> validateImportWorldOptions(options).mapAttempt(this::doImportWorld));
+        return options.keyOrName()
+                .fold(WorldKeyOrName::parse, Attempt::success)
+                .transform(ImportFailureReason.INVALID_WORLDNAME)
+                .failIf(keyOrName -> !worldNameChecker.isValidWorldName(keyOrName.usableName()),
+                        keyOrName -> worldActionResult(ImportFailureReason.INVALID_WORLDNAME, keyOrName))
+                .failIf(keyOrName -> keyOrName.isKey() && !WorldCreatorCompatibility.canCreateWorldWithKey(),
+                        keyOrName -> worldActionResult(ImportFailureReason.NAMESPACEDKEY_UNSUPPORTED, keyOrName))
+                .failIf(worldStore::isLoadedWorld,
+                        keyOrName -> worldActionResult(ImportFailureReason.WORLD_EXIST_LOADED, keyOrName))
+                .failIf(worldStore::isUnloadedWorld,
+                        keyOrName -> worldActionResult(ImportFailureReason.WORLD_EXIST_UNLOADED, keyOrName))
+                .map(keyOrName -> new KeyOrNameWithOptions<>(keyOrName, options))
+                .mapAttempt(pair -> BukkitCompatibility.getWorldByNameOrKey(pair.keyOrName())
+                        .map(bukkitWorld -> doImportBukkitWorld(pair, bukkitWorld))
+                        .getOrElse(() -> validateImportWorldOptions(pair).mapAttempt(this::doImportWorld)));
     }
 
-    private Attempt<ImportWorldOptions, ImportFailureReason> validateImportWorldOptions(ImportWorldOptions options) {
-        String worldName = options.worldName();
-        if (!worldNameChecker.isValidWorldName(worldName)) {
-            return worldActionResult(ImportFailureReason.INVALID_WORLDNAME, worldName);
-        } else if (options.doFolderCheck() && !worldNameChecker.isValidWorldFolder(worldName)) {
-            return worldActionResult(ImportFailureReason.WORLD_FOLDER_INVALID, worldName);
+    private Attempt<KeyOrNameWithOptions<ImportWorldOptions>, ImportFailureReason> validateImportWorldOptions(
+            KeyOrNameWithOptions<ImportWorldOptions> keyOrNameWithOptions) {
+        WorldKeyOrName keyOrName = keyOrNameWithOptions.keyOrName();
+        if (keyOrNameWithOptions.options().doFolderCheck()) {
+            //todo This is a duplicate of folder check in load world
+            WorldNameChecker.FolderStatus folderStatus = worldNameChecker.checkFolder(keyOrName);
+            if (!folderStatus.isLoadable()) {
+                return worldActionResult(ImportFailureReason.WORLD_FOLDER_INVALID, keyOrName);
+            }
+            if (folderStatus == WorldNameChecker.FolderStatus.REQUIRES_MIGRATION) {
+                Logging.info("World '%s' will be automatically migrated by PaperMC to the new dimension " +
+                                "location. If you face any issue with migration, please contact PaperMC support!",
+                        keyOrName);
+            }
         }
-        return worldActionResult(options);
+        return worldActionResult(keyOrNameWithOptions);
     }
 
     private Attempt<LoadedMultiverseWorld, ImportFailureReason> doImportWorld(
-            ImportWorldOptions options) {
-        String generatorString = generatorProvider.parseGeneratorString(options.worldName(), options.generator());
-        WorldCreator worldCreator = WorldCreator.name(options.worldName())
-                .environment(options.environment());
+            KeyOrNameWithOptions<ImportWorldOptions> keyOrNameWithOptions) {
+        WorldKeyOrName keyOrName = keyOrNameWithOptions.keyOrName();
+        ImportWorldOptions options = keyOrNameWithOptions.options();
+        String generatorString = generatorProvider.parseGeneratorString(keyOrName.usableName(), options.generator());
+        WorldCreator worldCreator = WorldCreatorCompatibility.ofKeyOrName(keyOrName)
+                .environment(options.environment())
+                .generatorSettings(options.generatorSettings());
 
-        return addBiomeProviderToCreator(worldCreator, options.worldName(), options.biome())
+        return addBiomeProviderToCreator(worldCreator, keyOrName.usableName(), options.biome())
                 .mapAttempt(creator -> addGeneratorToCreator(creator, generatorString))
                 .mapAttempt(this::createBukkitWorld)
                 .transform(ImportFailureReason.WORLD_CREATOR_FAILED)
@@ -322,11 +367,15 @@ public final class WorldManager {
                         bukkitWorld,
                         generatorString,
                         options.biome(),
+                        options.generatorSettings(),
                         options.useSpawnAdjust()))
                 .peek(loadedWorld -> pluginManager.callEvent(new MVWorldImportedEvent(loadedWorld)));
     }
 
-    private Attempt<LoadedMultiverseWorld, ImportFailureReason> doImportBukkitWorld(ImportWorldOptions options, World bukkitWorld) {
+    private Attempt<LoadedMultiverseWorld, ImportFailureReason> doImportBukkitWorld(
+            KeyOrNameWithOptions<ImportWorldOptions> keyOrNameWithOptions, World bukkitWorld) {
+        WorldKeyOrName keyOrName = keyOrNameWithOptions.keyOrName();
+        ImportWorldOptions options = keyOrNameWithOptions.options();
         if (options.environment() != bukkitWorld.getEnvironment()) {
             return Attempt.failure(ImportFailureReason.BUKKIT_ENVIRONMENT_MISMATCH,
                     Replace.WORLD.with(bukkitWorld.getName()),
@@ -334,18 +383,21 @@ public final class WorldManager {
                     replace("{mvEnvironment}").with(options.environment().name()));
         }
 
+        //todo: check for key mismatch?
+
         LoadedMultiverseWorld loadedWorld = newLoadedMultiverseWorld(
                 bukkitWorld,
-                generatorProvider.parseGeneratorString(options.worldName(), options.generator()),
+                generatorProvider.parseGeneratorString(keyOrName.usableName(), options.generator()),
                 options.biome(),
+                options.generatorSettings(),
                 options.useSpawnAdjust());
         pluginManager.callEvent(new MVWorldImportedEvent(loadedWorld));
         return Attempt.success(loadedWorld);
     }
 
-    private MultiverseWorld newMultiverseWorld(String worldName, WorldConfig worldConfig) {
-        MultiverseWorld mvWorld = new MultiverseWorld(worldName, worldConfig, config);
-        worldsMap.put(mvWorld.getName().toLowerCase(Locale.ENGLISH), mvWorld);
+    private MultiverseWorld newMultiverseWorld(WorldConfig worldConfig) {
+        MultiverseWorld mvWorld = new MultiverseWorld(worldConfig, config);
+        worldStore.putUnloadedWorld(mvWorld);
         corePermissions.addWorldPermissions(mvWorld);
         return mvWorld;
     }
@@ -358,22 +410,28 @@ public final class WorldManager {
      * @param adjustSpawn   Whether to adjust spawn.
      */
     private LoadedMultiverseWorld newLoadedMultiverseWorld(
-            @NotNull World world, @Nullable String generator, @Nullable String biome, boolean adjustSpawn) {
-        WorldConfig worldConfig = worldsConfigManager.addWorldConfig(world.getName());
+            @NotNull World world,
+            @Nullable String generator,
+            @Nullable String biome,
+            @Nullable String generatorSettings,
+            boolean adjustSpawn) {
+        WorldConfig worldConfig = worldsConfigManager.addWorldConfig(world.getKey());
 
         // Properties from multiverse input
         worldConfig.setAdjustSpawn(adjustSpawn);
         worldConfig.setGenerator(generator == null ? "" : generator);
         worldConfig.setBiome(biome == null ? "" : biome);
+        worldConfig.setGeneratorSettings(generatorSettings == null ? "" : generatorSettings);
 
         // Properties from the bukkit world
+        worldConfig.setLegacyWorldName(world.getName());
         worldConfig.setDifficulty(world.getDifficulty());
         worldConfig.setKeepSpawnInMemory(world.getKeepSpawnInMemory());
-        worldConfig.setScale(getCoordinateScale(world));
+        worldConfig.setScale(WorldCompatibility.getCoordinateScale(world));
 
         worldConfig.save();
 
-        newMultiverseWorld(world.getName(), worldConfig);
+        newMultiverseWorld(worldConfig);
         LoadedMultiverseWorld loadedWorld = new LoadedMultiverseWorld(
                 world,
                 worldConfig,
@@ -382,23 +440,12 @@ public final class WorldManager {
                 locationManipulation,
                 entityPurger
         );
-        loadedWorldsMap.put(loadedWorld.getName().toLowerCase(Locale.ENGLISH), loadedWorld);
+        worldStore.putLoadedWorld(loadedWorld);
         saveWorldsConfig();
         pluginManager.callEvent(new MVWorldLoadedEvent(loadedWorld));
         return loadedWorld;
     }
 
-    private double getCoordinateScale(World world) {
-        if (PaperLib.isPaper()) {
-            return world.getCoordinateScale();
-        }
-        return switch (world.getEnvironment()) {
-            case NORMAL -> 1;
-            case NETHER -> 8;
-            default -> 1;
-        };
-    }
-
     /**
      * Loads an existing world in config.
      *
@@ -465,11 +512,19 @@ public final class WorldManager {
             return doLoadBukkitWorld(bukkitWorld, mvWorld);
         }
 
-        if (options.doFolderCheck() && !worldNameChecker.isValidWorldFolder(mvWorld.getName())) {
-            return worldActionResult(LoadFailureReason.WORLD_FOLDER_INVALID, mvWorld.getName());
+        if (options.doFolderCheck()) {
+            WorldNameChecker.FolderStatus folderStatus = worldNameChecker.checkFolder(mvWorld.getOfflineWorldFolder());
+            if (!folderStatus.isLoadable()) {
+                return worldActionResult(LoadFailureReason.WORLD_FOLDER_INVALID, mvWorld.getName());
+            }
+            if (folderStatus == WorldNameChecker.FolderStatus.REQUIRES_MIGRATION) {
+                Logging.info("World '%s' will be automatically migrated by PaperMC to the new dimension " +
+                        "location. If you face any issue with migration, please contact PaperMC support!",
+                        mvWorld.getName());
+            }
         }
 
-        WorldCreator worldCreator = WorldCreator.name(mvWorld.getName())
+        WorldCreator worldCreator = WorldCreatorCompatibility.ofNameAndKey(mvWorld.getKey(), mvWorld.getName())
                 .environment(mvWorld.getEnvironment())
                 .seed(mvWorld.getSeed());
         return addBiomeProviderToCreator(worldCreator, mvWorld.getName(), mvWorld.getBiome())
@@ -492,7 +547,23 @@ public final class WorldManager {
     }
 
     private Attempt<LoadedMultiverseWorld, LoadFailureReason> newLoadedMultiverseWorld(MultiverseWorld mvWorld, World bukkitWorld) {
-        WorldConfig worldConfig = worldsConfigManager.getWorldConfig(mvWorld.getName()).get(); //TODO: null check here, but logically it should never be null.
+        WorldConfig worldConfig = mvWorld.getWorldConfig();
+
+        if (worldConfig.getWorldKeyOrName().isName() && mvWorld.getName().equalsIgnoreCase(bukkitWorld.getName())) {
+            // do migration of namespaced key
+            Logging.info("Migrating world config for '%s' to use namespaced key '%s'...",
+                    mvWorld.getName(), bukkitWorld.getKey());
+            worldConfig = worldsConfigManager.migrateWorldConfigKey(worldConfig, bukkitWorld.getKey());
+            mvWorld.setWorldConfig(worldConfig);
+        }
+
+        if (!bukkitWorld.getKey().equals(mvWorld.getKey())) {
+            return Attempt.failure(LoadFailureReason.BUKKIT_NAMESPACED_KEY_MISMATCH,
+                    Replace.WORLD.with(mvWorld.getName()),
+                    replace("{bukkitNamespace}").with(bukkitWorld.getKey()),
+                    replace("{mvNamespace}").with(mvWorld.getKey()));
+        }
+
         LoadedMultiverseWorld loadedWorld = new LoadedMultiverseWorld(
                 bukkitWorld,
                 worldConfig,
@@ -501,7 +572,7 @@ public final class WorldManager {
                 locationManipulation,
                 entityPurger
         );
-        loadedWorldsMap.put(loadedWorld.getName().toLowerCase(Locale.ENGLISH), loadedWorld);
+        worldStore.putLoadedWorld(loadedWorld);
         saveWorldsConfig();
         pluginManager.callEvent(new MVWorldLoadedEvent(loadedWorld));
         return Attempt.success(loadedWorld);
@@ -535,12 +606,10 @@ public final class WorldManager {
                 success -> removeLoadedMultiverseWorld(world));
     }
 
-    private Attempt<MultiverseWorld, UnloadFailureReason> removeLoadedMultiverseWorld(@NotNull LoadedMultiverseWorld world) {
-        MultiverseWorld mvWorld = Objects.requireNonNull(loadedWorldsMap.remove(world.getName()),
-                "For some reason, the loaded world isn't in the map... BUGGG");
-        Logging.fine("Removed MultiverseWorld from map: " + world.getName());
-        var unloadedWorld = Objects.requireNonNull(worldsMap.get(world.getName()),
-                "For some reason, the unloaded world isn't in the map... BUGGG");
+    private Attempt<MultiverseWorld, UnloadFailureReason> removeLoadedMultiverseWorld(@NotNull LoadedMultiverseWorld mvWorld) {
+        MultiverseWorld unloadedWorld = worldStore.getUnloadedWorldRef(mvWorld.getKey().toString()).getOrElseThrow(
+                () -> new IllegalStateException("Unloaded ref of world not found: " + mvWorld));
+        worldStore.removeLoadedWorld(mvWorld);
         mvWorld.getWorldConfig().setMVWorld(unloadedWorld);
         pluginManager.callEvent(new MVWorldUnloadedEvent(mvWorld));
         return worldActionResult(unloadedWorld);
@@ -630,11 +699,15 @@ public final class WorldManager {
      */
     private Attempt<String, RemoveFailureReason> removeWorldFromConfig(@NotNull MultiverseWorld world) {
         // Remove world from config
-        worldsMap.remove(world.getName());
-        world.getWorldConfig().deferenceMVWorld();
-        worldsConfigManager.deleteWorldConfig(world.getName());
+        worldStore.removeWorld(world);
+
+        WorldConfig worldConfig = world.getWorldConfig();
+        worldConfig.deferenceMVWorld();
+        worldsConfigManager.deleteWorldConfig(worldConfig);
         saveWorldsConfig();
+
         corePermissions.removeWorldPermissions(world);
+
         pluginManager.callEvent(new MVWorldRemovedEvent(world));
         return worldActionResult(world.getName());
     }
@@ -691,6 +764,7 @@ public final class WorldManager {
     private Attempt<File, DeleteFailureReason> validateWorldToDelete(
             @NotNull LoadedMultiverseWorld world) {
         return world.getBukkitWorld().map(World::getWorldFolder)
+                .peek(folder -> Logging.finer("World folder for world %s is at: %s", world.getName(), folder.getPath()))
                 .filter(worldNameChecker::isValidWorldFolder)
                 .map(this::<File, DeleteFailureReason>worldActionResult)
                 .getOrElse(() -> {
@@ -706,91 +780,91 @@ public final class WorldManager {
      * @return The result of the clone.
      */
     public Attempt<LoadedMultiverseWorld, CloneFailureReason> cloneWorld(@NotNull CloneWorldOptions options) {
-        return cloneWorldValidateWorld(options)
+        return parseCloneWorldOptionsNewWorld(options)
                 .mapAttempt(this::cloneWorldCopyFolder)
-                .mapAttempt(validatedOptions -> {
+                .mapAttempt(keyOrNameWithOptions -> {
                     ImportWorldOptions importWorldOptions = ImportWorldOptions
-                            .worldName(validatedOptions.newWorldName())
-                            .biome(validatedOptions.world().getBiome())
-                            .environment(validatedOptions.world().getEnvironment())
-                            .generator(validatedOptions.world().getGenerator());
+                            .worldKeyOrName(keyOrNameWithOptions.keyOrName())
+                            .biome(options.fromWorld().getBiome())
+                            .environment(options.fromWorld().getEnvironment())
+                            .generator(options.fromWorld().getGenerator());
                     return importWorld(importWorldOptions).transform(CloneFailureReason.IMPORT_FAILED);
                 })
                 .onSuccess(newWorld -> {
                     cloneWorldTransferData(options, newWorld);
                     if (options.keepWorldConfig()) {
-                        newWorld.setSpawnLocation(options.world().getSpawnLocation());
+                        // Special case for spawn location as it's considered a hidden config
+                        newWorld.setSpawnLocation(options.fromWorld().getSpawnLocation());
                     }
                     saveWorldsConfig();
-                    pluginManager.callEvent(new MVWorldClonedEvent(newWorld, options.world()));
+                    pluginManager.callEvent(new MVWorldClonedEvent(newWorld, options.fromWorld()));
                 });
     }
 
-    private Attempt<CloneWorldOptions, CloneFailureReason> cloneWorldValidateWorld(
+    private Attempt<KeyOrNameWithOptions<CloneWorldOptions>, CloneFailureReason> parseCloneWorldOptionsNewWorld(
             @NotNull CloneWorldOptions options) {
-        String newWorldName = options.newWorldName();
-        if (!worldNameChecker.isValidWorldName(newWorldName)) {
-            Logging.severe("Invalid world name: " + newWorldName);
-            return worldActionResult(CloneFailureReason.INVALID_WORLDNAME, newWorldName);
-        }
-        if (isLoadedWorld(newWorldName)) {
-            Logging.severe("World already loaded when attempting to clone: " + newWorldName);
-            return worldActionResult(CloneFailureReason.WORLD_EXIST_LOADED, newWorldName);
-        }
-        if (isWorld(newWorldName)) {
-            Logging.severe("World already exist unloaded: " + newWorldName);
-            return worldActionResult(CloneFailureReason.WORLD_EXIST_UNLOADED, newWorldName);
-        }
-        if (worldNameChecker.hasWorldFolder(newWorldName)) {
-            return worldActionResult(CloneFailureReason.WORLD_EXIST_FOLDER, newWorldName);
-        }
-        return worldActionResult(options);
+        return options.newWorldKeyOrName()
+                .fold(WorldKeyOrName::parse, Attempt::success)
+                .transform(CloneFailureReason.INVALID_WORLDNAME)
+                .failIf(keyOrName -> !worldNameChecker.isValidWorldName(keyOrName.usableName()),
+                        keyOrName -> worldActionResult(CloneFailureReason.INVALID_WORLDNAME, keyOrName))
+                .failIf(keyOrName -> keyOrName.isKey() && !WorldCreatorCompatibility.canCreateWorldWithKey(),
+                        keyOrName -> worldActionResult(CloneFailureReason.NAMESPACEDKEY_UNSUPPORTED, keyOrName))
+                .failIf(worldStore::isLoadedWorld,
+                        keyOrName -> worldActionResult(CloneFailureReason.WORLD_EXIST_LOADED, keyOrName))
+                .failIf(worldStore::isWorld,
+                        keyOrName -> worldActionResult(CloneFailureReason.WORLD_EXIST_UNLOADED, keyOrName))
+                .failIf(worldNameChecker::hasWorldFolder,
+                        keyOrName -> worldActionResult(CloneFailureReason.WORLD_EXIST_FOLDER, keyOrName))
+                .failIf(keyOrName -> !worldNameChecker.isValidWorldFolder(options.fromWorld().getOfflineWorldFolder()),
+                        keyOrName -> worldActionResult(CloneFailureReason.FROM_WORLD_FOLDER_INVALID,
+                                options.fromWorld().getName()))
+                .map(keyOrName -> new KeyOrNameWithOptions<>(keyOrName, options));
     }
 
-    private Attempt<CloneWorldOptions, CloneFailureReason> cloneWorldCopyFolder(@NotNull CloneWorldOptions options) {
+    private Attempt<KeyOrNameWithOptions<CloneWorldOptions>, CloneFailureReason> cloneWorldCopyFolder(
+            @NotNull KeyOrNameWithOptions<CloneWorldOptions> keyOrNameWithOptions) {
+        WorldKeyOrName newWorldkeyOrName = keyOrNameWithOptions.keyOrName();
+        CloneWorldOptions options = keyOrNameWithOptions.options();
         if (options.saveBukkitWorld()) {
-            Logging.finer("Saving bukkit world before cloning: " + options.world().getName());
-            options.world().getBukkitWorld().peek(this::saveWorldWithFlush);
+            options.fromWorld().asLoadedWorld().peek(loadedWorld -> {
+                Logging.finer("Saving world before cloning: " + loadedWorld.getName());
+                loadedWorld.getBukkitWorld().peek(bukkitWorld -> WorldCompatibility.saveWithFlush(bukkitWorld, true));
+            });
         }
-        File worldFolder = options.world().getBukkitWorld().map(World::getWorldFolder).get();
-        File newWorldFolder = new File(Bukkit.getWorldContainer(), options.newWorldName());
+        File worldFolder = WorldFolderResolver.resolve(options.fromWorld());
+        File newWorldFolder = WorldFolderResolver.resolve(newWorldkeyOrName);
         return fileUtils.copyFolder(worldFolder, newWorldFolder, CLONE_IGNORE_FILES).fold(
                 exception -> worldActionResult(CloneFailureReason.COPY_FAILED,
-                        options.world().getName(), exception),
-                success -> worldActionResult(options));
-    }
-
-    // This method is only available since 1.21
-    private final Method saveWithFlush = ReflectHelper.getMethod(World.class, "save", boolean.class);
-    private void saveWorldWithFlush(World world) {
-        if (saveWithFlush != null) {
-            Logging.fine("Using world save method with flush...");
-            ReflectHelper.invokeMethod(world, saveWithFlush, true);
-        } else {
-            world.save();
-        }
+                        options.fromWorld().getName(), exception),
+                success -> worldActionResult(keyOrNameWithOptions));
     }
 
     private void cloneWorldTransferData(@NotNull CloneWorldOptions options, @NotNull LoadedMultiverseWorld newWorld) {
-        DataTransfer<LoadedMultiverseWorld> dataTransfer = transferData(options, options.world());
-        dataTransfer.pasteAllTo(newWorld);
-    }
-
-    private DataTransfer<LoadedMultiverseWorld> transferData(
-            @NotNull KeepWorldSettingsOptions options, @NotNull LoadedMultiverseWorld world) {
-        DataTransfer<LoadedMultiverseWorld> dataTransfer = new DataTransfer<>();
-
         if (options.keepWorldConfig()) {
-            dataTransfer.addDataStore(new WorldConfigStore(), world);
-        }
-        if (options.keepGameRule()) {
-            dataTransfer.addDataStore(new GameRulesStore(), world);
-        }
-        if (options.keepWorldBorder()) {
-            dataTransfer.addDataStore(new WorldBorderStore(), world);
+            new DataTransfer<MultiverseWorld>()
+                    .addDataStore(new WorldConfigStore<>(), options.fromWorld())
+                    .pasteAllTo(newWorld);
         }
 
-        return dataTransfer;
+        newWorld.getBukkitWorld().peek(bukkitWorld -> {
+            if (!options.keepWorldBorder()) {
+                WorldBorder worldBorder = bukkitWorld.getWorldBorder();
+                worldBorder.reset();
+            }
+
+            if (!options.keepGameRule()) {
+                Arrays.stream(bukkitWorld.getGameRules())
+                        .map(gameRuleName -> GameRule.getByName(gameRuleName))
+                        .filter(Objects::nonNull)
+                        .forEach(gameRule -> {
+                            Object gameRuleDefault = bukkitWorld.getGameRuleDefault(gameRule);
+                            if (gameRuleDefault != null) {
+                                bukkitWorld.setGameRule(gameRule, gameRuleDefault);
+                            }
+                        });
+            }
+        });
     }
 
     /**
@@ -801,14 +875,16 @@ public final class WorldManager {
      */
     public Attempt<LoadedMultiverseWorld, RegenFailureReason> regenWorld(@NotNull RegenWorldOptions options) {
         LoadedMultiverseWorld world = options.world();
-        DataTransfer<LoadedMultiverseWorld> dataTransfer = transferData(options, world);
+        DataTransfer<LoadedMultiverseWorld> dataTransfer = regenWorldTransferData(options, world);
         boolean shouldKeepSpawnLocation = options.keepWorldConfig() && options.seed() == world.getSeed();
         Location spawnLocation = world.getSpawnLocation();
-
-        CreateWorldOptions createWorldOptions = CreateWorldOptions.worldName(world.getName())
+        CreateWorldOptions createWorldOptions = CreateWorldOptions.worldKeyOrName(world.worldConfig.getWorldKeyOrName())
+                .biome(world.getBiome())
+                .bonusChest(world.getBukkitWorld().map(WorldCompatibility::hasBonusChest).getOrElse(false))
                 .environment(world.getEnvironment())
                 .generateStructures(world.canGenerateStructures().getOrElse(true))
                 .generator(world.getGenerator())
+                .generatorSettings(world.getGeneratorSettings())
                 .seed(options.seed())
                 .useSpawnAdjust(!shouldKeepSpawnLocation && world.getAdjustSpawn())
                 .worldType(world.getWorldType().getOrElse(WorldType.NORMAL))
@@ -829,18 +905,35 @@ public final class WorldManager {
                 });
     }
 
+    private DataTransfer<LoadedMultiverseWorld> regenWorldTransferData(
+            @NotNull KeepWorldSettingsOptions options, @NotNull LoadedMultiverseWorld world) {
+        DataTransfer<LoadedMultiverseWorld> dataTransfer = new DataTransfer<>();
+
+        if (options.keepWorldConfig()) {
+            dataTransfer.addDataStore(new WorldConfigStore<>(), world);
+        }
+        if (options.keepGameRule()) {
+            dataTransfer.addDataStore(new GameRulesStore(), world);
+        }
+        if (options.keepWorldBorder()) {
+            dataTransfer.addDataStore(new WorldBorderStore(), world);
+        }
+
+        return dataTransfer;
+    }
+
     private <T, F extends FailureReason> Attempt<T, F> worldActionResult(@NotNull T value) {
         return Attempt.success(value);
     }
 
-    private <T, F extends FailureReason> Attempt<T, F> worldActionResult(
-            @NotNull F failureReason, @NotNull String worldName) {
-        return Attempt.failure(failureReason, Replace.WORLD.with(worldName));
+    private <T, F extends FailureReason> Attempt.Failure<T, F> worldActionResult(
+            @NotNull F failureReason, @NotNull Object worldName) {
+        return Attempt.failureRef(failureReason, Replace.WORLD.with(worldName));
     }
 
-    private <T, F extends FailureReason> Attempt<T, F> worldActionResult(
+    private <T, F extends FailureReason> Attempt.Failure<T, F> worldActionResult(
             @NotNull F failureReason, @NotNull String worldName, @NotNull Throwable error) {
-        return Attempt.failure(failureReason, Replace.WORLD.with(worldName), Replace.ERROR.with(error));
+        return Attempt.failureRef(failureReason, Replace.WORLD.with(worldName), Replace.ERROR.with(error));
     }
 
     private Attempt<WorldCreator, WorldCreatorFailureReason> addBiomeProviderToCreator(
@@ -936,17 +1029,13 @@ public final class WorldManager {
      * Checks based on folder contents and name.
      *
      * @return A list of all potential worlds.
+     *
+     * @deprecated Use {@link PotentialWorldFinder#findPotentialWorlds()} instead.
      */
+    @Deprecated(forRemoval = true, since = "5.7")
+    @ApiStatus.ScheduledForRemoval(inVersion = "6.0")
     public List<String> getPotentialWorlds() {
-        File[] files = Bukkit.getWorldContainer().listFiles();
-        if (files == null) {
-            return Collections.emptyList();
-        }
-        return Arrays.stream(files)
-                .filter(file -> !isWorld(file.getName()))
-                .filter(worldNameChecker::isValidWorldFolder)
-                .map(File::getName)
-                .toList();
+        return potentialWorldFinder.get().findPotentialWorlds();
     }
 
     /**
@@ -968,9 +1057,7 @@ public final class WorldManager {
      * @return The world if it exists.
      */
     public Option<MultiverseWorld> getWorld(@Nullable String worldName) {
-        return getLoadedWorld(worldName)
-                .map(world -> (MultiverseWorld) world)
-                .orElse(() -> getUnloadedWorld(worldName));
+        return worldStore.getWorld(worldName);
     }
 
     /**
@@ -981,9 +1068,7 @@ public final class WorldManager {
      * @return The world if it exists.
      */
     public Option<MultiverseWorld> getWorldByNameOrAlias(@Nullable String worldNameOrAlias) {
-        return getLoadedWorldByNameOrAlias(worldNameOrAlias)
-                .map(world -> (MultiverseWorld) world)
-                .orElse(() -> getUnloadedWorldByNameOrAlias(worldNameOrAlias));
+        return getWorld(worldStore.translateAlias(worldNameOrAlias));
     }
 
     /**
@@ -993,14 +1078,15 @@ public final class WorldManager {
      * <p>If you want only unloaded worlds, use {@link #getUnloadedWorlds()}. If you want only loaded worlds, use
      * {@link #getLoadedWorlds()}.</p>
      *
+     * <p>Note that this is an unmodifiable copy of the current worlds. It will not update as worlds are added/removed.
+     * Call it everytime you need the most updated list of worlds.</p>
+     *
      * @return A list of all worlds that may or may not be loaded.
      */
+    @Unmodifiable
+    @NotNull
     public Collection<MultiverseWorld> getWorlds() {
-        return worldsMap.values().stream()
-                .map(world -> getLoadedWorld(world)
-                        .map(loadedWorld -> (MultiverseWorld) loadedWorld)
-                        .getOrElse(world))
-                .toList();
+        return worldStore.getWorlds();
     }
 
     /**
@@ -1010,7 +1096,7 @@ public final class WorldManager {
      * @return True if the world is a world is known to multiverse, but may or may not be loaded.
      */
     public boolean isWorld(@Nullable String worldName) {
-        return worldName != null && worldsMap.containsKey(worldName.toLowerCase(Locale.ENGLISH));
+        return worldName != null && worldStore.getWorld(worldName).isDefined();
     }
 
     /**
@@ -1020,9 +1106,7 @@ public final class WorldManager {
      * @return The world if it exists.
      */
     public Option<MultiverseWorld> getUnloadedWorld(@Nullable String worldName) {
-        return isLoadedWorld(worldName)
-                ? Option.none()
-                : Option.of(worldName).flatMap(name -> Option.of(worldsMap.get(name.toLowerCase(Locale.ENGLISH))));
+        return worldStore.getUnloadedWorld(worldName);
     }
 
     /**
@@ -1032,18 +1116,7 @@ public final class WorldManager {
      * @return The world if it exists.
      */
     public Option<MultiverseWorld> getUnloadedWorldByNameOrAlias(@Nullable String worldNameOrAlias) {
-        return getUnloadedWorld(worldNameOrAlias).orElse(() -> getUnloadedWorldByAlias(worldNameOrAlias));
-    }
-
-    private Option<MultiverseWorld> getUnloadedWorldByAlias(@Nullable String alias) {
-        if (alias == null || alias.isEmpty()) {
-            return Option.none();
-        }
-        String colourlessAlias = ChatTextFormatter.removeColor(alias);
-        return Option.ofOptional(worldsMap.values().stream()
-                .filter(world -> !world.isLoaded())
-                .filter(world -> world.getColourlessAlias().equalsIgnoreCase(colourlessAlias))
-                .findFirst());
+        return getUnloadedWorld(worldStore.translateAlias(worldNameOrAlias));
     }
 
     /**
@@ -1051,10 +1124,10 @@ public final class WorldManager {
      *
      * @return A list of all worlds that are not loaded.
      */
+    @Unmodifiable
+    @NotNull
     public Collection<MultiverseWorld> getUnloadedWorlds() {
-        return worldsMap.values().stream()
-                .filter(world -> !world.isLoaded())
-                .toList();
+        return worldStore.getUnloadedWorlds();
     }
 
     /**
@@ -1094,8 +1167,7 @@ public final class WorldManager {
      * @return The multiverse world if it exists.
      */
     public Option<LoadedMultiverseWorld> getLoadedWorld(@Nullable String worldName) {
-        return Option.of(worldName)
-                .flatMap(name -> Option.of(loadedWorldsMap.get(name.toLowerCase(Locale.ENGLISH))));
+        return Option.of(worldName).flatMap(worldStore::getLoadedWorld);
     }
 
     /**
@@ -1105,28 +1177,21 @@ public final class WorldManager {
      * @return The multiverse world if it exists.
      */
     public Option<LoadedMultiverseWorld> getLoadedWorldByNameOrAlias(@Nullable String worldNameOrAlias) {
-        return getLoadedWorld(worldNameOrAlias)
-                .orElse(() -> getLoadedWorldByAlias(worldNameOrAlias));
-    }
-
-    private Option<LoadedMultiverseWorld> getLoadedWorldByAlias(@Nullable String alias) {
-        if (alias == null || alias.isEmpty()) {
-            return Option.none();
-        }
-        return Option.ofOptional(loadedWorldsMap.values().stream()
-                .filter(world -> world.getColourlessAlias()
-                        .equalsIgnoreCase(ChatTextFormatter.removeColor(alias)))
-                .findFirst());
+        return getLoadedWorld(worldStore.translateAlias(worldNameOrAlias));
     }
 
     /**
      * Get a read-only list of all multiverse worlds that are loaded.
      *
+     * <p>Note that this is an unmodifiable copy of the current worlds. It will not update as worlds are added/removed.
+     * Call it everytime you need the most updated list of worlds.</p>
+     *
      * @return A list of all multiverse worlds that are loaded.
      */
+    @Unmodifiable
+    @NotNull
     public Collection<LoadedMultiverseWorld> getLoadedWorlds() {
-        return loadedWorldsMap.values().stream()
-                .toList();
+        return worldStore.getLoadedWorlds();
     }
 
     /**
@@ -1156,7 +1221,7 @@ public final class WorldManager {
      * @return True if the world is a multiverse world that is loaded.
      */
     public boolean isLoadedWorld(@Nullable String worldName) {
-        return worldName != null && loadedWorldsMap.containsKey(worldName.toLowerCase(Locale.ENGLISH));
+        return worldName != null && worldStore.getLoadedWorld(worldName).isDefined();
     }
 
     /**
@@ -1184,4 +1249,18 @@ public final class WorldManager {
                     failure.printStackTrace();
                 });
     }
+
+    WorldStore getWorldStore() {
+        return worldStore;
+    }
+
+    /**
+     * A simple pair wrapper for convenience to pass both the world key or name and the options together between methods
+     * when parsing world options.
+     *
+     * @param keyOrName The world key or name.
+     * @param options   The world options.
+     * @param <T> The world options type.
+     */
+    private record KeyOrNameWithOptions<T>(WorldKeyOrName keyOrName, T options) { }
 }

src/main/java/org/mvplugins/multiverse/core/world/WorldStore.java

@@ -0,0 +1,270 @@
+package org.mvplugins.multiverse.core.world;
+
+import com.google.common.base.Strings;
+import com.google.common.collect.HashMultimap;
+import com.google.common.collect.Multimap;
+import io.vavr.control.Option;
+import jakarta.inject.Inject;
+import org.bukkit.NamespacedKey;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+import org.jetbrains.annotations.Unmodifiable;
+import org.jvnet.hk2.annotations.Service;
+import org.mvplugins.multiverse.core.utils.CaseInsensitiveStringMap;
+import org.mvplugins.multiverse.core.world.key.WorldKeyOrName;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+import java.util.Objects;
+
+@Service
+final class WorldStore {
+
+    /**
+     * Only loaded worlds, i.e. will be empty if all worlds are unloaded.
+     */
+    private final List<LoadedMultiverseWorld> loadedList;
+
+    /**
+     * Only unloaded worlds, i.e. will be empty if all worlds are loaded.
+     */
+    private final List<MultiverseWorld> unloadedList;
+
+    /**
+     * Contains single reference to all worlds, either loaded or unloaded ref depending on the world's current status.
+     */
+    private final List<MultiverseWorld> worldList;
+
+    /**
+     * Maps all key and key to loaded ref.
+     */
+    private final Map<String, LoadedMultiverseWorld> loadedMap;
+
+    /**
+     * Maps all key and key to unloaded ref.
+     */
+    private final Map<String, MultiverseWorld> unloadedMap;
+
+    /**
+     * Maps colorless alias to world key. As alias may not be unique, this is a multimap.
+     */
+    private final Multimap<String, String> aliasMap;
+
+    @Inject
+    private WorldStore() {
+        this.loadedList = new ArrayList<>();
+        this.unloadedList = new ArrayList<>();
+        this.worldList = new ArrayList<>();
+
+        this.loadedMap = new CaseInsensitiveStringMap<>();
+        this.unloadedMap = new CaseInsensitiveStringMap<>();
+        this.aliasMap = HashMultimap.create();
+    }
+
+    void putUnloadedWorld(MultiverseWorld world) {
+        if (world instanceof LoadedMultiverseWorld) {
+            throw new IllegalArgumentException("Loaded world cannot be put in unloaded map");
+        }
+
+        unloadedMap.put(world.getKey().toString(), world);
+        unloadedMap.put(world.getName(), world);
+
+        unloadedList.add(world);
+        worldList.add(world);
+    }
+
+    void putLoadedWorld(LoadedMultiverseWorld world) {
+        loadedMap.put(world.getKey().toString(), world);
+        loadedMap.put(world.getName(), world);
+
+        unloadedList.remove(unloadedMap.get(world.getKey().toString()));
+        worldList.remove(unloadedMap.get(world.getKey().toString()));
+
+        loadedList.add(world);
+        worldList.add(world);
+    }
+
+    void removeWorld(MultiverseWorld world) {
+        LoadedMultiverseWorld loadedRef = loadedMap.get(world.getKey().toString());
+        MultiverseWorld unloadedRef = unloadedMap.get(world.getKey().toString());
+
+        // remove from list
+        unloadedList.remove(unloadedRef);
+        loadedList.remove(loadedRef);
+        worldList.remove(unloadedRef);
+        worldList.remove(loadedRef);
+
+        // remove from maps
+        loadedMap.remove(world.getKey().toString());
+        unloadedMap.remove(world.getName());
+
+        unloadedMap.remove(world.getKey().toString());
+        unloadedMap.remove(world.getName());
+
+        // remove alias
+        aliasMap.remove(world.getColourlessAlias(), world.getKey().toString());
+    }
+
+    void removeLoadedWorld(LoadedMultiverseWorld world) {
+        // remove from list
+        loadedList.remove(world);
+        worldList.remove(world);
+
+        // remove from maps
+        loadedMap.remove(world.getKey().toString());
+        loadedMap.remove(world.getName());
+
+        // Add back unloaded
+        unloadedList.add(unloadedMap.get(world.getKey().toString()));
+    }
+
+    void changeAlias(@Nullable String oldAlias, @Nullable String newAlias, @NotNull MultiverseWorld world) {
+        if (Objects.equals(oldAlias, newAlias)) {
+            // nothing changed, ignore
+            return;
+        }
+        if (!Strings.isNullOrEmpty(oldAlias)) {
+            aliasMap.remove(oldAlias, world.getKey().toString());
+        }
+        if (!Strings.isNullOrEmpty(newAlias)) {
+            aliasMap.put(newAlias, world.getKey().toString());
+        }
+    }
+
+    @Unmodifiable
+    @NotNull
+    List<MultiverseWorld> getWorlds() {
+        return List.copyOf(worldList);
+    }
+
+    @Unmodifiable
+    @NotNull
+    List<LoadedMultiverseWorld> getLoadedWorlds() {
+        return List.copyOf(loadedList);
+    }
+
+    @Unmodifiable
+    @NotNull
+    List<MultiverseWorld> getUnloadedWorlds() {
+        return List.copyOf(unloadedList);
+    }
+
+    @NotNull
+    Option<MultiverseWorld> getWorld(@Nullable WorldKeyOrName keyOrName) {
+        return keyOrName == null
+                ? Option.none()
+                : getWorld(keyOrName.usableKey()).orElse(() -> getWorld(keyOrName.usableName()));
+    }
+
+    @NotNull
+    Option<MultiverseWorld> getWorld(@Nullable NamespacedKey worldKey) {
+        return Option.of(worldKey).map(NamespacedKey::toString).flatMap(this::getWorld);
+    }
+
+    @NotNull
+    Option<MultiverseWorld> getWorld(@Nullable String worldKeyString) {
+        return Option.of((MultiverseWorld) loadedMap.get(worldKeyString))
+                .orElse(() -> Option.of(unloadedMap.get(worldKeyString)));
+    }
+
+    boolean isWorld(@Nullable WorldKeyOrName keyOrName) {
+        return keyOrName != null && (isWorld(keyOrName.usableKey()) || isWorld(keyOrName.usableName()));
+    }
+
+    boolean isWorld(@Nullable NamespacedKey worldKey) {
+        return getWorld(worldKey).isDefined();
+    }
+
+    boolean isWorld(@Nullable String worldKeyString) {
+        return getWorld(worldKeyString).isDefined();
+    }
+
+    @NotNull
+    Option<LoadedMultiverseWorld> getLoadedWorld(@Nullable WorldKeyOrName keyOrName) {
+        return keyOrName == null
+                ? Option.none()
+                : getLoadedWorld(keyOrName.usableKey()).orElse(() -> getLoadedWorld(keyOrName.usableName()));
+    }
+
+    @NotNull
+    Option<LoadedMultiverseWorld> getLoadedWorld(@Nullable NamespacedKey worldKey) {
+        return Option.of(worldKey).map(NamespacedKey::toString).flatMap(this::getLoadedWorld);
+    }
+
+    @NotNull
+    Option<LoadedMultiverseWorld> getLoadedWorld(@Nullable String worldKeyString) {
+        return Option.of(loadedMap.get(worldKeyString))
+                .filter(MultiverseWorld::isLoaded);
+    }
+
+    boolean isLoadedWorld(@Nullable WorldKeyOrName keyOrName) {
+        return keyOrName != null && (isLoadedWorld(keyOrName.usableKey()) || isLoadedWorld(keyOrName.usableName()));
+    }
+
+    boolean isLoadedWorld(@Nullable NamespacedKey worldKey) {
+        return getLoadedWorld(worldKey).isDefined();
+    }
+
+    boolean isLoadedWorld(@Nullable String worldKeyString) {
+        return getLoadedWorld(worldKeyString).isDefined();
+    }
+
+    @NotNull
+    Option<MultiverseWorld> getUnloadedWorld(@Nullable WorldKeyOrName keyOrName) {
+        return keyOrName == null
+                ? Option.none()
+                : getUnloadedWorld(keyOrName.usableKey()).orElse(() -> getUnloadedWorld(keyOrName.usableName()));
+    }
+
+    @NotNull
+    Option<MultiverseWorld> getUnloadedWorld(@Nullable NamespacedKey worldKey) {
+        return Option.of(worldKey).map(NamespacedKey::toString).flatMap(this::getUnloadedWorld);
+    }
+
+    @NotNull
+    Option<MultiverseWorld> getUnloadedWorld(@Nullable String worldKeyString) {
+        return Option.of(unloadedMap.get(worldKeyString))
+                .filter(world -> !world.isLoaded());
+    }
+
+    boolean isUnloadedWorld(@Nullable WorldKeyOrName keyOrName) {
+        return keyOrName != null && (isUnloadedWorld(keyOrName.usableKey()) || isUnloadedWorld(keyOrName.usableName()));
+    }
+
+    boolean isUnloadedWorld(@Nullable NamespacedKey worldKey) {
+        return getUnloadedWorld(worldKey).isDefined();
+    }
+
+    boolean isUnloadedWorld(@Nullable String worldKeyString) {
+        return getUnloadedWorld(worldKeyString).isDefined();
+    }
+
+    @NotNull
+    Option<MultiverseWorld> getUnloadedWorldRef(@Nullable WorldKeyOrName keyOrName) {
+        return keyOrName == null
+                ? Option.none()
+                : getUnloadedWorldRef(keyOrName.usableKey()).orElse(() -> getUnloadedWorldRef(keyOrName.usableName()));
+    }
+
+    @NotNull
+    Option<MultiverseWorld> getUnloadedWorldRef(@Nullable NamespacedKey worldKey) {
+        return Option.of(worldKey).map(NamespacedKey::toString).flatMap(this::getUnloadedWorldRef);
+    }
+
+    @NotNull
+    Option<MultiverseWorld> getUnloadedWorldRef(@Nullable String worldKeyString) {
+        return Option.of(unloadedMap.get(worldKeyString));
+    }
+
+    @Nullable
+    String translateAlias(@Nullable String worldNameOrAlias) {
+        if (Strings.isNullOrEmpty(worldNameOrAlias)) {
+            return null;
+        }
+        //TODO: Not sure if we should fail if there is multiple alias of the same name, but for now just return the first one
+        return aliasMap.get(worldNameOrAlias).stream()
+                .findFirst()
+                .orElse(worldNameOrAlias);
+    }
+}

src/main/java/org/mvplugins/multiverse/core/world/WorldsConfigManager.java

@@ -10,6 +10,7 @@ import com.dumptruckman.minecraft.util.Logging;
 import io.vavr.control.Option;
 import io.vavr.control.Try;
 import jakarta.inject.Inject;
+import org.bukkit.NamespacedKey;
 import org.bukkit.configuration.ConfigurationSection;
 import org.bukkit.configuration.InvalidConfigurationException;
 import org.bukkit.configuration.file.YamlConfiguration;
@@ -17,6 +18,9 @@ import org.jetbrains.annotations.NotNull;
 import org.jvnet.hk2.annotations.Service;
 
 import org.mvplugins.multiverse.core.MultiverseCore;
+import org.mvplugins.multiverse.core.utils.result.Attempt;
+import org.mvplugins.multiverse.core.world.key.WorldKeyOrName;
+import org.mvplugins.multiverse.core.world.key.WorldKeyParseFailReason;
 
 import static java.nio.file.StandardCopyOption.COPY_ATTRIBUTES;
 import static java.nio.file.StandardCopyOption.REPLACE_EXISTING;
@@ -28,7 +32,7 @@ import static java.nio.file.StandardCopyOption.REPLACE_EXISTING;
 final class WorldsConfigManager {
     private static final String CONFIG_FILENAME = "worlds.yml";
 
-    private final SortedMap<String, WorldConfig> worldConfigMap;
+    private final SortedMap<WorldKeyOrName, WorldConfig> worldConfigMap;
     private final File worldConfigFile;
     private YamlConfiguration worldsConfig;
 
@@ -47,7 +51,7 @@ final class WorldsConfigManager {
      *
      * @return A {@link NewAndRemovedWorlds} record.
      */
-    public Try<NewAndRemovedWorlds> load() {
+    Try<NewAndRemovedWorlds> load() {
         return Try.of(() -> {
             loadWorldYmlFile();
             return parseNewAndRemovedWorlds();
@@ -113,7 +117,7 @@ final class WorldsConfigManager {
                     config.set("worlds", null);
 
                     for (Map.Entry<String, ConfigurationSection> entry : worldConfigMap.entrySet()) {
-                        config.set(encodeWorldName(entry.getKey()), entry.getValue());
+                        config.set(encodeConfigKey(entry.getKey()), entry.getValue());
                     }
                     config.save(worldConfigFile);
                 })
@@ -162,33 +166,39 @@ final class WorldsConfigManager {
      * @return A tuple containing a list of the new WorldConfigs added and a list of the worlds removed from the config.
      */
     private NewAndRemovedWorlds parseNewAndRemovedWorlds() {
-        List<String> allWorldsInConfig = worldsConfig.getKeys(false)
+        List<WorldKeyOrName> allWorldsInConfig = worldsConfig.getKeys(false)
                 .stream()
-                .map(this::decodeWorldName)
+                .map(keyStr -> decodeConfigKey(keyStr)
+                        .onFailure(reason ->
+                                Logging.warning("Failed to parse world key '%s' in config: %s", keyStr, reason))
+                        .getOrNull())
+                .filter(Objects::nonNull)
                 .toList();
 
         List<WorldConfig> newWorldsAdded = new ArrayList<>();
 
-        for (String worldName : allWorldsInConfig) {
-            getWorldConfig(worldName)
-                    .peek(config -> config.load(getWorldConfigSection(worldName)))
+        for (WorldKeyOrName worldKeyStr : allWorldsInConfig) {
+            getWorldConfig(worldKeyStr)
+                    .peek(config -> config.load(getWorldConfigSection(worldKeyStr))
+                            .onFailure(e -> Logging.warning("Failed to load world config for world '%s': %s",
+                                    worldKeyStr, e.getMessage())))
                     .orElse(() -> {
                         WorldConfig newWorldConfig = new WorldConfig(
-                                worldName,
-                                getWorldConfigSection(worldName),
+                                worldKeyStr,
+                                getWorldConfigSection(worldKeyStr),
                                 multiverseCore);
-                        worldConfigMap.put(worldName, newWorldConfig);
+                        worldConfigMap.put(worldKeyStr, newWorldConfig);
                         newWorldsAdded.add(newWorldConfig);
                         return Option.of(newWorldConfig);
                     })
                     .peek(WorldConfig::save);
         }
 
-        List<String> worldsRemoved = worldConfigMap.keySet().stream()
+        List<WorldKeyOrName> worldsRemoved = worldConfigMap.keySet().stream()
                 .filter(worldName -> !allWorldsInConfig.contains(worldName))
                 .toList();
 
-        for (String s : worldsRemoved) {
+        for (WorldKeyOrName s : worldsRemoved) {
             worldConfigMap.remove(s);
         }
 
@@ -200,7 +210,7 @@ final class WorldsConfigManager {
      *
      * @return Whether the worlds.yml file has been loaded.
      */
-    public boolean isLoaded() {
+    boolean isLoaded() {
         return worldsConfig != null;
     }
 
@@ -209,17 +219,17 @@ final class WorldsConfigManager {
      *
      * @return Whether the save was successful or the error that occurred.
      */
-    public Try<Void> save() {
+    Try<Void> save() {
         return Try.run(() -> {
             if (!isLoaded()) {
                 throw new IllegalStateException("WorldsConfigManager is not loaded!");
             }
             worldsConfig = new YamlConfiguration();
-            worldConfigMap.forEach((worldName, worldConfig) -> {
+            worldConfigMap.forEach((keyOrName, worldConfig) -> {
                 worldConfig.save().onFailure(e -> {
-                    throw new RuntimeException("Failed to save world config: " + worldName, e);
+                    throw new RuntimeException("Failed to save world %s in config: " + keyOrName, e);
                 });
-                worldsConfig.set(encodeWorldName(worldName), worldConfig.getConfigurationSection());
+                worldsConfig.set(encodeConfigKey(keyOrName), worldConfig.getConfigurationSection());
             });
             worldsConfig.save(worldConfigFile);
         }).onFailure(e -> {
@@ -228,63 +238,81 @@ final class WorldsConfigManager {
     }
 
     /**
-     * Gets the {@link WorldConfig} instance of all worlds in the worlds.yml file.
+     * Gets the {@link WorldConfig} instance of a world in the worlds.yml file.
      *
-     * @param worldName The name of the world to check.
+     * @param keyOrName The target key to get
      * @return The {@link WorldConfig} instance of the world, or empty option if it doesn't exist.
      */
-    public @NotNull Option<WorldConfig> getWorldConfig(@NotNull String worldName) {
-        return Option.of(worldConfigMap.get(worldName));
+    @NotNull Option<WorldConfig> getWorldConfig(@NotNull WorldKeyOrName keyOrName) {
+        return Option.of(worldConfigMap.get(keyOrName));
+    }
+
+    @NotNull WorldConfig migrateWorldConfigKey(@NotNull WorldConfig worldConfig, @NotNull NamespacedKey toKey) {
+        worldConfig.save();
+        WorldKeyOrName newKeyOrName = WorldKeyOrName.parseKey(toKey);
+        WorldConfig migratedWorldConfig = new WorldConfig(
+                newKeyOrName,
+                worldConfig.getConfigurationSection(),
+                multiverseCore
+        );
+        deleteWorldConfig(worldConfig);
+        worldConfigMap.put(newKeyOrName, migratedWorldConfig);
+        return migratedWorldConfig;
     }
 
     /**
      * Add a new world to the worlds.yml file. If a world with the given name already exists, an exception is thrown.
      *
-     * @param worldName The name of the world to add.
+     * @param namespacedKey The target key to add
      * @return The newly created {@link WorldConfig} instance.
      */
-    public @NotNull WorldConfig addWorldConfig(@NotNull String worldName) {
-        if (worldConfigMap.containsKey(worldName)) {
-            throw new IllegalArgumentException("WorldConfig for world " + worldName + " already exists.");
+    @NotNull WorldConfig addWorldConfig(@NotNull NamespacedKey namespacedKey) {
+        WorldKeyOrName keyOrName = WorldKeyOrName.parseKey(namespacedKey);
+        if (worldConfigMap.containsKey(keyOrName)) {
+            throw new IllegalStateException("WorldConfig for world " + namespacedKey + " already exists.");
         }
-        WorldConfig worldConfig = new WorldConfig(worldName, getWorldConfigSection(worldName), multiverseCore);
-        worldConfigMap.put(worldName, worldConfig);
+        WorldConfig worldConfig = new WorldConfig(keyOrName, getWorldConfigSection(keyOrName), multiverseCore);
+        worldConfigMap.put(keyOrName, worldConfig);
         return worldConfig;
     }
 
     /**
      * Deletes the world config for the given world.
      *
-     * @param worldName The name of the world to delete.
+     * @param worldConfig The target world config to delete
      */
-    public void deleteWorldConfig(@NotNull String worldName) {
-        worldConfigMap.remove(worldName);
-        worldsConfig.set(encodeWorldName(worldName), null);
+    void deleteWorldConfig(@NotNull WorldConfig worldConfig) {
+        worldConfigMap.remove(worldConfig.getWorldKeyOrName());
+        worldsConfig.set(encodeConfigKey(worldConfig.getWorldKeyOrName()), null);
     }
 
     /**
      * Gets the {@link ConfigurationSection} for the given world in the worlds.yml file. If the section doesn't exist,
      * it is created.
      *
-     * @param worldName The name of the world.
+     * @param keyOrName the config key of the world to get the configuration section for.
      * @return The {@link ConfigurationSection} for the given world.
      */
-    private ConfigurationSection getWorldConfigSection(String worldName) {
-        worldName = encodeWorldName(worldName);
-        return worldsConfig.isConfigurationSection(worldName)
-                ? worldsConfig.getConfigurationSection(worldName)
-                : worldsConfig.createSection(worldName);
+    @NotNull
+    private ConfigurationSection getWorldConfigSection(@NotNull WorldKeyOrName keyOrName) {
+        String encodeWorldKey = encodeConfigKey(keyOrName);
+        ConfigurationSection section = worldsConfig.getConfigurationSection(encodeWorldKey);
+        return section == null ? worldsConfig.createSection(encodeWorldKey) : section;
+    }
+
+    private String encodeConfigKey(@NotNull WorldKeyOrName worldKeyOrName) {
+        return encodeConfigKey(worldKeyOrName.serialise());
     }
 
     /**
-     * Dot is a special character in YAML that causes sub-path issues.
+     * Remove dot . with [dot] as it is a special character in YAML that causes sub-path issues.
      */
-    private String encodeWorldName(String worldName) {
+    private String encodeConfigKey(@NotNull String worldName) {
         return worldName.replace(".", "[dot]");
     }
 
-    private String decodeWorldName(String worldName) {
-        return worldName.replace("[dot]", ".");
+    private Attempt<WorldKeyOrName, WorldKeyParseFailReason> decodeConfigKey(@NotNull String worldKeyStr) {
+        return WorldKeyOrName.parse(worldKeyStr.replace("[dot]", "."));
     }
 
     private static final class ConfigMigratedException extends RuntimeException {

src/main/java/org/mvplugins/multiverse/core/world/entity/EntityPurger.java

@@ -1,6 +1,7 @@
 package org.mvplugins.multiverse.core.world.entity;
 
 import org.bukkit.entity.Entity;
+import org.bukkit.entity.Player;
 import org.bukkit.entity.SpawnCategory;
 import org.jvnet.hk2.annotations.Service;
 import org.mvplugins.multiverse.core.world.LoadedMultiverseWorld;
@@ -40,25 +41,24 @@ public final class EntityPurger {
     public int purgeEntities(LoadedMultiverseWorld world, SpawnCategory... spawnCategories) {
         Set<SpawnCategory> spawnCategoriesSet = Set.of(spawnCategories);
         AtomicInteger purgeCount = new AtomicInteger(0);
-        world.getBukkitWorld().peek(bukkitWorld -> {
-            for (Entity entity : bukkitWorld.getEntities()) {
-                if (spawnCategoriesSet.contains(entity.getSpawnCategory())) {
+        world.getBukkitWorld().peek(bukkitWorld -> bukkitWorld.getEntities().stream()
+                .filter(entity -> !(entity instanceof Player))
+                .filter(entity -> spawnCategoriesSet.contains(entity.getSpawnCategory()))
+                .forEach(entity -> {
                     entity.remove();
                     purgeCount.incrementAndGet();
-                }
-            }
-        });
+                }));
         return purgeCount.get();
     }
 
     public int purgeAllEntities(LoadedMultiverseWorld world) {
         AtomicInteger purgeCount = new AtomicInteger(0);
-        world.getBukkitWorld().peek(bukkitWorld -> {
-            for (Entity entity : bukkitWorld.getEntities()) {
-                entity.remove();
-                purgeCount.incrementAndGet();
-            }
-        });
+        world.getBukkitWorld().peek(bukkitWorld -> bukkitWorld.getEntities().stream()
+                .filter(entity -> !(entity instanceof Player))
+                .forEach(entity -> {
+                    entity.remove();
+                    purgeCount.incrementAndGet();
+                }));
         return purgeCount.get();
     }
 }

src/main/java/org/mvplugins/multiverse/core/world/entity/EntitySpawnConfig.java

@@ -4,6 +4,7 @@ import com.dumptruckman.minecraft.util.Logging;
 import org.bukkit.configuration.ConfigurationSection;
 import org.bukkit.configuration.MemoryConfiguration;
 import org.bukkit.entity.Entity;
+import org.bukkit.entity.EntityType;
 import org.bukkit.entity.SpawnCategory;
 import org.jetbrains.annotations.ApiStatus;
 import org.mvplugins.multiverse.core.config.CoreConfig;
@@ -33,6 +34,11 @@ public final class EntitySpawnConfig {
                 ));
     }
 
+    @ApiStatus.AvailableSince("5.7")
+    public boolean shouldAllowSpawn(EntityType entityType) {
+        return getSpawnCategoryConfig(SpawnCategoryMapper.getSpawnCategory(entityType)).shouldAllowSpawn(entityType);
+    }
+
     public boolean shouldAllowSpawn(Entity entity) {
         return getSpawnCategoryConfig(entity.getSpawnCategory()).shouldAllowSpawn(entity);
     }

src/main/java/org/mvplugins/multiverse/core/world/entity/SpawnCategoryMapper.java

@@ -4,10 +4,8 @@ import com.dumptruckman.minecraft.util.Logging;
 import io.vavr.control.Try;
 import org.bukkit.entity.EntityType;
 import org.bukkit.entity.SpawnCategory;
-import org.jvnet.hk2.annotations.Service;
 import org.mvplugins.multiverse.core.utils.ReflectHelper;
 
-import java.lang.reflect.Field;
 import java.lang.reflect.Method;
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -21,26 +19,27 @@ import java.util.Map;
  */
 final class SpawnCategoryMapper {
 
+    private static final Map<EntityType, SpawnCategory> entityTypeToSpawnCategoryMap;
+    private static final Map<SpawnCategory, List<EntityType>> spawnCategoryMap;
+
     static {
+        entityTypeToSpawnCategoryMap = new HashMap<>();
+        spawnCategoryMap = new HashMap<>();
         buildSpawnCategoryMap();
     }
 
-    private static Map<SpawnCategory, List<EntityType>> spawnCategoryMap;
-
     private static void buildSpawnCategoryMap() {
-        spawnCategoryMap = new HashMap<>();
-
-        Class<?> entityTypeClass = ReflectHelper.getClass("net.minecraft.world.entity.EntityType");
+        Class<?> entityTypeClass = ReflectHelper.tryGetClass("net.minecraft.world.entity.EntityType").getOrNull();
         if (entityTypeClass == null) {
             Logging.warning("Failed to find EntityType class. SpawnCategoryMapper will not work.");
             return;
         }
-        Method getCategoryMethod = ReflectHelper.getMethod(entityTypeClass, "getCategory");
+        Method getCategoryMethod = ReflectHelper.tryGetMethod(entityTypeClass, "getCategory").getOrNull();
         if (getCategoryMethod == null) {
             Logging.warning("Failed to find getCategory method. SpawnCategoryMapper will not work.");
             return;
         }
-        Class<?> craftSpawnCategoryClass = ReflectHelper.getClass("org.bukkit.craftbukkit.util.CraftSpawnCategory");
+        Class<?> craftSpawnCategoryClass = ReflectHelper.tryGetClass("org.bukkit.craftbukkit.util.CraftSpawnCategory").getOrNull();
         if (craftSpawnCategoryClass == null) {
             Logging.warning("Failed to find CraftSpawnCategory class. SpawnCategoryMapper will not work.");
             return;
@@ -53,25 +52,26 @@ final class SpawnCategoryMapper {
             Logging.warning("Failed to find toBukkit method. SpawnCategoryMapper will not work.");
             return;
         }
-        Field[] entityTypeFields = entityTypeClass.getFields();
-        for (Field entityTypeField : entityTypeFields) {
-            String entityName = entityTypeField.getName();
-            EntityType entityType = Try.of(() -> EntityType.valueOf(entityName)).getOrNull();
-            if (entityType == null) {
-                continue;
-            }
-            Object nmsEntityType = ReflectHelper.getFieldValue(null, entityTypeField, entityTypeClass);
-            Object nsmMobCategory = ReflectHelper.invokeMethod(nmsEntityType, getCategoryMethod);
-            if (nsmMobCategory == null) {
-                continue;
-            }
-            Object bukkitSpawnCategory = ReflectHelper.invokeMethod(null, toBukkitMethod, nsmMobCategory);
-            if (!(bukkitSpawnCategory instanceof SpawnCategory spawnCategory)) {
-                continue;
-            }
-            spawnCategoryMap.computeIfAbsent(spawnCategory, ignore -> new ArrayList<>())
-                    .add(entityType);
-        }
+        Arrays.stream(entityTypeClass.getFields()).forEach(entityTypeField -> Try.of(() -> EntityType.valueOf(entityTypeField.getName()))
+                .peek(entityType -> ReflectHelper.tryGetStaticFieldValue(entityTypeField, entityTypeClass)
+                        .flatMap(nmsEntityType -> ReflectHelper.tryInvokeMethod(nmsEntityType, getCategoryMethod))
+                        .flatMap(nsmMobCategory -> ReflectHelper.tryInvokeStaticMethod(toBukkitMethod, nsmMobCategory))
+                        .filter(bukkitSpawnCategory -> bukkitSpawnCategory instanceof SpawnCategory)
+                        .map(bukkitSpawnCategory -> (SpawnCategory) bukkitSpawnCategory)
+                        .peek(bukkitSpawnCategory -> entityTypeToSpawnCategoryMap.put(entityType, bukkitSpawnCategory))
+                        .peek(bukkitSpawnCategory -> spawnCategoryMap
+                                .computeIfAbsent(bukkitSpawnCategory, ignore -> new ArrayList<>())
+                                .add(entityType))));
+    }
+
+    /**
+     * Gets the spawn category that the given entity type is in.
+     *
+     * @param entityType The entity type
+     * @return The spawn category that the given entity type is in, or null if it cannot be determined
+     */
+    static SpawnCategory getSpawnCategory(EntityType entityType) {
+        return entityTypeToSpawnCategoryMap.get(entityType);
     }
 
     /**

src/main/java/org/mvplugins/multiverse/core/world/helpers/DataStore.java

@@ -9,7 +9,9 @@ import org.bukkit.GameRule;
 import org.bukkit.World;
 import org.jvnet.hk2.annotations.Service;
 import org.mvplugins.multiverse.core.config.handle.StringPropertyHandle;
+import org.mvplugins.multiverse.core.utils.compatibility.WorldBorderCompatibility;
 import org.mvplugins.multiverse.core.world.LoadedMultiverseWorld;
+import org.mvplugins.multiverse.core.world.MultiverseWorld;
 
 /**
  * A data store for storing and restoring data from an object.
@@ -90,14 +92,14 @@ public interface DataStore<T> {
     /**
      * A {@link DataStore} for storing and restoring world properties for a multiverse world.
      */
-    class WorldConfigStore implements DataStore<LoadedMultiverseWorld> {
+    class WorldConfigStore<T extends MultiverseWorld> implements DataStore<T> {
         private Map<String, Object> configMap;
 
         /**
          * {@inheritDoc}
          */
         @Override
-        public WorldConfigStore copyFrom(LoadedMultiverseWorld world) {
+        public WorldConfigStore<T> copyFrom(T world) {
             this.configMap = new HashMap<>();
             StringPropertyHandle worldPropertyHandler = world.getStringPropertyHandle();
             worldPropertyHandler.getAllPropertyNames().forEach(name -> worldPropertyHandler.getProperty(name)
@@ -111,7 +113,7 @@ public interface DataStore<T> {
          * {@inheritDoc}
          */
         @Override
-        public WorldConfigStore pasteTo(LoadedMultiverseWorld world) {
+        public WorldConfigStore<T> pasteTo(T world) {
             if (configMap == null) {
                 return this;
             }
@@ -139,14 +141,16 @@ public interface DataStore<T> {
          */
         @Override
         public WorldBorderStore copyFrom(LoadedMultiverseWorld world) {
-            world.getBukkitWorld().peek(bukkitWorld -> {
-                borderCenterX = bukkitWorld.getWorldBorder().getCenter().getX();
-                borderCenterZ = bukkitWorld.getWorldBorder().getCenter().getZ();
-                borderDamageAmount = bukkitWorld.getWorldBorder().getDamageAmount();
-                borderDamageBuffer = bukkitWorld.getWorldBorder().getDamageBuffer();
-                borderSize = bukkitWorld.getWorldBorder().getSize();
-                borderTimeRemaining = bukkitWorld.getWorldBorder().getWarningTime();
-            });
+            world.getBukkitWorld()
+                    .map(World::getWorldBorder)
+                    .peek(worldBorder -> {
+                        borderCenterX = worldBorder.getCenter().getX();
+                        borderCenterZ = worldBorder.getCenter().getZ();
+                        borderDamageAmount = worldBorder.getDamageAmount();
+                        borderDamageBuffer = worldBorder.getDamageBuffer();
+                        borderSize = worldBorder.getSize();
+                        borderTimeRemaining = WorldBorderCompatibility.getWarningTimeTicks(worldBorder);
+                    });
             return this;
         }
 
@@ -155,13 +159,15 @@ public interface DataStore<T> {
          */
         @Override
         public WorldBorderStore pasteTo(LoadedMultiverseWorld world) {
-            world.getBukkitWorld().peek(bukkitWorld -> {
-                bukkitWorld.getWorldBorder().setCenter(borderCenterX, borderCenterZ);
-                bukkitWorld.getWorldBorder().setDamageAmount(borderDamageAmount);
-                bukkitWorld.getWorldBorder().setDamageBuffer(borderDamageBuffer);
-                bukkitWorld.getWorldBorder().setSize(borderSize);
-                bukkitWorld.getWorldBorder().setWarningTime(borderTimeRemaining);
-            });
+            world.getBukkitWorld()
+                    .map(World::getWorldBorder)
+                    .peek(worldBorder -> {
+                        worldBorder.setCenter(borderCenterX, borderCenterZ);
+                        worldBorder.setDamageAmount(borderDamageAmount);
+                        worldBorder.setDamageBuffer(borderDamageBuffer);
+                        worldBorder.setSize(borderSize);
+                        WorldBorderCompatibility.setWarningTimeTicks(worldBorder, borderTimeRemaining);
+                    });
             return this;
         }
     }

src/main/java/org/mvplugins/multiverse/core/world/helpers/DimensionFinder.java

@@ -4,6 +4,7 @@ import com.dumptruckman.minecraft.util.Logging;
 import io.vavr.control.Option;
 import jakarta.inject.Inject;
 import org.bukkit.World.Environment;
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 import org.jvnet.hk2.annotations.Service;
 import org.mvplugins.multiverse.core.config.CoreConfig;
@@ -19,6 +20,24 @@ import java.util.regex.Pattern;
 @Service
 public final class DimensionFinder {
 
+    /**
+     * Default world for nether worlds, The default is "%overworld_nether%", which means that the nether world of
+     * "world" will be named "world_nether".
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static final DimensionFormat DEFAULT_NETHER_FORMAT = new DimensionFormat("%overworld%_nether");
+
+    /**
+     * Default world name format for end worlds. The default is "%overworld%_the_end", which means that the end world
+     * of "world" will be named "world_the_end".
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static final DimensionFormat DEFAULT_END_FORMAT = new DimensionFormat("%overworld%_the_end");
+
     private final CoreConfig config;
     private final WorldManager worldManager;
 

src/main/java/org/mvplugins/multiverse/core/world/helpers/PlayerWorldTeleporter.java

@@ -7,9 +7,11 @@ import org.bukkit.Bukkit;
 import org.bukkit.Location;
 import org.bukkit.World;
 import org.bukkit.entity.Player;
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 import org.jvnet.hk2.annotations.Service;
 
+import org.mvplugins.multiverse.core.destination.DestinationInstance;
 import org.mvplugins.multiverse.core.teleportation.AsyncSafetyTeleporter;
 import org.mvplugins.multiverse.core.teleportation.TeleportFailureReason;
 import org.mvplugins.multiverse.core.utils.result.AsyncAttemptsAggregate;
@@ -84,6 +86,24 @@ public final class PlayerWorldTeleporter {
                 .getOrElse(AsyncAttemptsAggregate::emptySuccess);
     }
 
+    /**
+     * Transfers all players from the given world to the given destination.
+     *
+     * @param world                 The world to transfer players from.
+     * @param destinationInstance   The destination instance to transfer players to.
+     * @return A list of async futures that represent the teleportation result of each player.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public AsyncAttemptsAggregate<Void, TeleportFailureReason> transferAllFromWorldToDestination(
+            @NotNull LoadedMultiverseWorld world,
+            @NotNull DestinationInstance<?, ?> destinationInstance) {
+        return world.getPlayers()
+                .map(players -> safetyTeleporter.to(destinationInstance).teleport(players))
+                .getOrElse(AsyncAttemptsAggregate::emptySuccess);
+    }
+
     /**
      * Teleports all players to the given world's spawn location.
      *

src/main/java/org/mvplugins/multiverse/core/world/helpers/PotentialWorldFinder.java

@@ -0,0 +1,81 @@
+package org.mvplugins.multiverse.core.world.helpers;
+
+import io.vavr.control.Option;
+import jakarta.inject.Inject;
+import org.bukkit.Bukkit;
+import org.bukkit.NamespacedKey;
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Unmodifiable;
+import org.jvnet.hk2.annotations.Service;
+import org.mvplugins.multiverse.core.utils.compatibility.BukkitCompatibility;
+import org.mvplugins.multiverse.core.world.WorldManager;
+
+import java.io.File;
+import java.nio.file.Path;
+import java.util.Arrays;
+import java.util.List;
+import java.util.stream.Stream;
+
+/**
+ * Tool that traversals the server folders to find all potential worlds that can be imported, based on folder contents
+ * and name.
+ *
+ * @since 5.7
+ */
+@ApiStatus.AvailableSince("5.7")
+@Service
+public final class PotentialWorldFinder {
+
+    private final WorldManager worldManager;
+    private final WorldNameChecker worldNameChecker;
+
+    @Inject
+    private PotentialWorldFinder(@NotNull WorldManager worldManager, @NotNull WorldNameChecker worldNameChecker) {
+        this.worldManager = worldManager;
+        this.worldNameChecker = worldNameChecker;
+    }
+
+    /**
+     * Gets a list of all potential worlds that can be loaded from the server folders.
+     * Checks based on folder contents and name.
+     *
+     * @return A list of all potential worlds.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    @Unmodifiable
+    @NotNull
+    public List<String> findPotentialWorlds() {
+        return BukkitCompatibility.isUsingNewDimensionStorage()
+                ? Stream.concat(findFromDimensionsFolder(), findFromRootFolder()).toList()
+                : findFromRootFolder().toList();
+    }
+
+    private Stream<String> findFromRootFolder() {
+        Path worldContainer = Bukkit.getWorldContainer().toPath();
+        return Arrays.stream(listFolders(worldContainer))
+                .filter(worldNameChecker::isValidWorldFolder)
+                .map(File::getName)
+                .filter(worldNameChecker::isValidWorldName)
+                .filter(worldName -> !worldManager.isWorld(worldName));
+    }
+
+    private Stream<String> findFromDimensionsFolder() {
+        Path worldContainer = BukkitCompatibility.getWorldFoldersDirectory();
+        return Arrays.stream(listFolders(worldContainer))
+                .map(File::getName)
+                .flatMap(namespace -> Arrays.stream(listFolders(worldContainer.resolve(namespace)))
+                        .filter(worldNameChecker::isValidWorldFolder)
+                        .map(File::getName)
+                        .map(key -> namespace + ":" + key))
+                .filter(namespacedKey -> NamespacedKey.fromString(namespacedKey) != null)
+                .filter(namespacedKey -> !worldManager.isWorld(namespacedKey));
+    }
+
+    private @NotNull File[] listFolders(Path folder) {
+        return Option.of(folder.toFile().listFiles(File::isDirectory))
+                .getOrElse(() -> new File[0]);
+    }
+}

src/main/java/org/mvplugins/multiverse/core/world/helpers/WorldFolderResolver.java

@@ -0,0 +1,108 @@
+package org.mvplugins.multiverse.core.world.helpers;
+
+import org.bukkit.Bukkit;
+import org.bukkit.NamespacedKey;
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.NotNull;
+import org.mvplugins.multiverse.core.utils.compatibility.BukkitCompatibility;
+import org.mvplugins.multiverse.core.world.MultiverseWorld;
+import org.mvplugins.multiverse.core.world.key.WorldKeyOrName;
+
+import java.io.File;
+
+/**
+ * <p>Utility class for resolving the file system location of a world folder.</p>
+ *
+ * <p>This class handles the differences in world folder locations between server versions,
+ * particularly the new dimension storage system introduced in PaperMC 26.1 which stores worlds
+ * in a dimensions folder under the world level directory.</p>
+ *
+ * @since 5.7
+ */
+@ApiStatus.AvailableSince("5.7")
+public final class WorldFolderResolver {
+
+    /**
+     * Resolves the world folder file path for the given world key or name.
+     * <br />
+     * This method automatically selects the appropriate resolution method based on whether the server
+     * is using the new dimension storage system introduced in PaperMC 26.1.
+     *
+     * @param keyOrName The world key or name to resolve.
+     * @return The resolved world folder file.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    @NotNull
+    public static File resolve(@NotNull WorldKeyOrName keyOrName) {
+        return BukkitCompatibility.isUsingNewDimensionStorage()
+                ? resolveAsDimensionKey(keyOrName.usableKey())
+                : resolveAsLegacyWorldName(keyOrName.usableName());
+    }
+
+    /**
+     * Resolves the world folder file path for the given Multiverse world.
+     * <br />
+     * This method automatically selects the appropriate resolution method based on whether the server
+     * is using the new dimension storage system introduced in PaperMC 26.1.
+     *
+     * @param multiverseWorld The Multiverse world to resolve.
+     * @return The resolved world folder file.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    @NotNull
+    public static File resolve(@NotNull MultiverseWorld multiverseWorld) {
+        File dimensionKey = resolveAsDimensionKey(multiverseWorld.getKey());
+        File legacy = resolveAsLegacyWorldName(multiverseWorld.getName());
+        if (BukkitCompatibility.isUsingNewDimensionStorage()) {
+            return !dimensionKey.isDirectory() && legacy.isDirectory() ? legacy : dimensionKey;
+        }
+        return legacy;
+    }
+
+    /**
+     * Gets the world folder using the new dimension storage path format of {@code [namespace]/[key]}.
+     * <br />
+     * This method is only valid for PaperMC 26.1 and above. For earlier server versions,
+     * use {@link #resolveAsLegacyWorldName(String)} instead.
+     *
+     * @param namespacedKey The namespaced key of the world.
+     * @return The resolved world folder file using the new dimension storage format.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    @NotNull
+    public static File resolveAsDimensionKey(@NotNull NamespacedKey namespacedKey) {
+        return BukkitCompatibility.getWorldFoldersDirectory()
+                .resolve(namespacedKey.getNamespace())
+                .resolve(namespacedKey.getKey())
+                .toFile();
+    }
+
+    /**
+     * Gets the world folder using the legacy world name format from the server root directory.
+     * <br />
+     * This method is the default for server versions before PaperMC 26.1.
+     *
+     * @param worldName The name of the world.
+     * @return The resolved world folder file using the legacy world name format.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    @NotNull
+    public static File resolveAsLegacyWorldName(@NotNull String worldName) {
+        return Bukkit.getWorldContainer()
+                .toPath()
+                .resolve(worldName)
+                .toFile();
+    }
+
+    private WorldFolderResolver() {
+        throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
+    }
+}

src/main/java/org/mvplugins/multiverse/core/world/helpers/WorldNameChecker.java

@@ -1,15 +1,18 @@
 package org.mvplugins.multiverse.core.world.helpers;
 
 import java.io.File;
+import java.util.List;
 import java.util.Locale;
 import java.util.Set;
 
 import io.vavr.control.Option;
-import org.bukkit.Bukkit;
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.jvnet.hk2.annotations.Service;
 import org.mvplugins.multiverse.core.utils.REPatterns;
+import org.mvplugins.multiverse.core.utils.compatibility.BukkitCompatibility;
+import org.mvplugins.multiverse.core.world.key.WorldKeyOrName;
 
 /**
  * <p>Utility class in helping to check the status of a world name and it's associated world folder.</p>
@@ -29,6 +32,18 @@ public final class WorldNameChecker {
             "plugins",
             "versions");
 
+    private static final List<WorldFolderSchema> WORLD_FOLDER_SCHEMA = List.of(
+            // OLD
+            WorldFolderSchema.file("level.dat"),
+            WorldFolderSchema.folder("DIM1"),
+            WorldFolderSchema.folder("DIM-1"),
+            // NEW
+            WorldFolderSchema.file("paper-world.yml"),
+            WorldFolderSchema.folder("data"),
+            WorldFolderSchema.folder("entities"),
+            WorldFolderSchema.folder("poi"),
+            WorldFolderSchema.folder("region"));
+
     /**
      * Checks if a world name is valid.
      *
@@ -53,7 +68,7 @@ public final class WorldNameChecker {
                     if (name.isEmpty()) {
                         return NameStatus.EMPTY;
                     }
-                    if (BLACKLIST_NAMES.contains(name)) {
+                    if (!BukkitCompatibility.isUsingNewDimensionStorage() && BLACKLIST_NAMES.contains(name)) {
                         return NameStatus.BLACKLISTED;
                     }
                     if (!REPatterns.NAMESPACE_KEY.matcher(name).matches()) {
@@ -69,19 +84,54 @@ public final class WorldNameChecker {
      *
      * @param worldName The world name to check on.
      * @return True if the folder exists, else false.
+     *
+     * @deprecated Use {@link #hasWorldFolder(WorldKeyOrName)} instead, which is more robust and supports namespaced keys.
      */
+    @Deprecated(forRemoval = true, since = "5.7")
+    @ApiStatus.ScheduledForRemoval(inVersion = "6.0")
     public boolean hasWorldFolder(@Nullable String worldName) {
         return checkFolder(worldName) != FolderStatus.DOES_NOT_EXIST;
     }
 
+    /**
+     * Check if a world name has a world folder directory. It may not contain valid world data.
+     *
+     * @param worldKey The world key to check on.
+     * @return True if the folder exists, else false.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public boolean hasWorldFolder(@Nullable WorldKeyOrName worldKey) {
+        return checkFolder(worldKey) != FolderStatus.DOES_NOT_EXIST;
+    }
+
     /**
      * Checks if a world name has a valid world folder with basic world data.
      *
      * @param worldName The world name to check on.
      * @return True if check result is valid, else false.
+     *
+     * @deprecated Use {@link #isValidWorldFolder(WorldKeyOrName)} instead, which is more robust and supports
+     * namespaced keys.
      */
+    @Deprecated(forRemoval = true, since = "5.7")
+    @ApiStatus.ScheduledForRemoval(inVersion = "6.0")
     public boolean isValidWorldFolder(@Nullable String worldName) {
-        return checkFolder(worldName) == FolderStatus.VALID;
+        return checkFolder(worldName).loadable;
+    }
+
+    /**
+     * Checks if a world name has a valid world folder with basic world data.
+     *
+     * @param nameOrKey The world key to check on.
+     * @return True if check result is valid, else false.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public boolean isValidWorldFolder(@Nullable WorldKeyOrName nameOrKey) {
+        return checkFolder(nameOrKey).loadable;
     }
 
     /**
@@ -91,7 +141,7 @@ public final class WorldNameChecker {
      * @return True if check result is valid, else false.
      */
     public boolean isValidWorldFolder(@Nullable File worldFolder) {
-        return checkFolder(worldFolder) == FolderStatus.VALID;
+        return checkFolder(worldFolder).loadable;
     }
 
     /**
@@ -99,14 +149,45 @@ public final class WorldNameChecker {
      *
      * @param worldName The world name to check on.
      * @return The resulting folder status.
+     *
+     * @deprecated Use {@link #checkFolder(WorldKeyOrName)} instead, which is more robust and supports namespaced keys.
      */
+    @Deprecated(forRemoval = true, since = "5.7")
+    @ApiStatus.ScheduledForRemoval(inVersion = "6.0")
     @NotNull
     public FolderStatus checkFolder(@Nullable String worldName) {
         if (worldName == null) {
             return FolderStatus.DOES_NOT_EXIST;
         }
-        File worldFolder = new File(Bukkit.getWorldContainer(), worldName);
-        return checkFolder(worldFolder);
+
+        return WorldKeyOrName.parse(worldName)
+                .map(this::checkFolder)
+                .getOrElse(FolderStatus.NOT_A_WORLD);
+    }
+
+    /**
+     * Checks the current folder status for a world key or name.
+     *
+     * @param keyOrName The world key or name to check on.
+     * @return The resulting folder status.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    @NotNull
+    public FolderStatus checkFolder(@Nullable WorldKeyOrName keyOrName) {
+        if (keyOrName == null) {
+            return FolderStatus.DOES_NOT_EXIST;
+        }
+
+        if (BukkitCompatibility.isUsingNewDimensionStorage()) {
+            File oldWorldFolder = WorldFolderResolver.resolveAsLegacyWorldName(keyOrName.usableName());
+            if (checkFolder(oldWorldFolder) == FolderStatus.VALID) {
+                return FolderStatus.REQUIRES_MIGRATION;
+            }
+        }
+
+        return checkFolder(WorldFolderResolver.resolve(keyOrName));
     }
 
     /**
@@ -120,7 +201,7 @@ public final class WorldNameChecker {
         if (worldFolder == null || !worldFolder.exists() || !worldFolder.isDirectory()) {
             return FolderStatus.DOES_NOT_EXIST;
         }
-        if (!folderHasDat(worldFolder)) {
+        if (!folderWorldSchemaCheck(worldFolder)) {
             return FolderStatus.NOT_A_WORLD;
         }
         return FolderStatus.VALID;
@@ -133,9 +214,54 @@ public final class WorldNameChecker {
      * @param worldFolder   The File that may be a world.
      * @return True if it looks like a world, else false.
      */
-    private boolean folderHasDat(@NotNull File worldFolder) {
-        File[] files = worldFolder.listFiles((file, name) -> name.toLowerCase(Locale.ENGLISH).endsWith(".dat"));
-        return files != null && files.length > 0;
+    private boolean folderWorldSchemaCheck(@NotNull File worldFolder) {
+        return WORLD_FOLDER_SCHEMA.stream()
+                .filter(schema -> schema.check(worldFolder))
+                .count() >= 2;
+    }
+
+    /**
+     * Helper class to check if a file or folder exist.
+     */
+    private interface WorldFolderSchema {
+
+        static WorldFolderSchema file(String path) {
+            return new WorldFile(path);
+        }
+
+        static WorldFolderSchema folder(String path) {
+            return new WorldFolder(path);
+        }
+
+        boolean check(File worldFolder);
+
+        final class WorldFile implements WorldFolderSchema {
+            private final String path;
+
+            private WorldFile(String path) {
+                this.path = path;
+            }
+
+            @Override
+            public boolean check(File worldFolder) {
+                File thisFolder = worldFolder.toPath().resolve(path).toFile();
+                return thisFolder.exists() && thisFolder.isFile();
+            }
+        }
+
+        final class WorldFolder implements WorldFolderSchema {
+            private final String path;
+
+            private WorldFolder(String path) {
+                this.path = path;
+            }
+
+            @Override
+            public boolean check(File worldFolder) {
+                File thisFolder = worldFolder.toPath().resolve(path).toFile();
+                return thisFolder.exists() && thisFolder.isDirectory();
+            }
+        }
     }
 
     /**
@@ -170,16 +296,39 @@ public final class WorldNameChecker {
         /**
          * Folder is valid.
          */
-        VALID,
+        VALID(true),
+
+        /**
+         * This folder will cause PaperMC to migrate to new dimension world folder in 26.1+
+         */
+        REQUIRES_MIGRATION(true),
 
         /**
          * Folder exist, but contents in it doesnt look like a world.
          */
-        NOT_A_WORLD,
+        NOT_A_WORLD(false),
 
         /**
          * Folder does not exist.
          */
-        DOES_NOT_EXIST
+        DOES_NOT_EXIST(false),
+        ;
+
+        private final boolean loadable;
+
+        FolderStatus(boolean loadable) {
+            this.loadable = loadable;
+        }
+
+        /**
+         * Whether this folder status is loadable, meaning it has the basic world data and can be loaded as a world.
+         * Note that this does not guarantee the server will definitely load the world with no errors.
+         *
+         * @return True if folder probably is loadable by the server, else false.
+         */
+        @ApiStatus.AvailableSince("5.6")
+        public boolean isLoadable() {
+            return loadable;
+        }
     }
 }

src/main/java/org/mvplugins/multiverse/core/world/key/WorldKeyOrName.java

@@ -0,0 +1,394 @@
+package org.mvplugins.multiverse.core.world.key;
+
+import io.vavr.control.Either;
+import io.vavr.control.Option;
+import io.vavr.control.Try;
+import org.bukkit.NamespacedKey;
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+import org.mvplugins.multiverse.core.locale.message.LocalizableMessage;
+import org.mvplugins.multiverse.core.locale.message.Message;
+import org.mvplugins.multiverse.core.locale.message.MessageReplacement;
+import org.mvplugins.multiverse.core.utils.ServerProperties;
+import org.mvplugins.multiverse.core.utils.compatibility.UnsafeValuesCompatibility;
+import org.mvplugins.multiverse.core.utils.result.Attempt;
+import org.mvplugins.multiverse.core.world.helpers.DimensionFinder;
+
+import java.util.Locale;
+import java.util.Objects;
+
+/**
+ * Represents either a world key or a world name, with methods to parse from strings and retrieve the key or name.
+ *
+ * @since 5.7
+ */
+@ApiStatus.AvailableSince("5.7")
+public sealed abstract class WorldKeyOrName implements Comparable<WorldKeyOrName>, LocalizableMessage permits WorldKeyOrName.Key, WorldKeyOrName.Name {
+
+    private static final String DEFAULT_OVERWORLD_KEY = "overworld";
+    private static final String DEFAULT_NETHER_KEY = "the_nether";
+    private static final String DEFAULT_END_KEY = "the_end";
+
+    /**
+     * Parse a string into a {@link WorldKeyOrName} instance.
+     * <p>
+     * The provided input will be interpreted as a namespaced key if it contains a ':' character,
+     * otherwise it will be treated as a world name.
+     *
+     * @param nameOrKey The input string to parse, may be a world name or a namespaced key string
+     * @return An {@link Attempt} containing either a parsed {@link WorldKeyOrName} on success or a
+     * {@link WorldKeyParseFailReason} describing the failure
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static Attempt<WorldKeyOrName, WorldKeyParseFailReason> parse(@Nullable String nameOrKey) {
+        if (nameOrKey == null || nameOrKey.isEmpty()) {
+            return Attempt.failure(WorldKeyParseFailReason.EMPTY);
+        }
+        return nameOrKey.contains(":") ? parseKey(nameOrKey) : parseName(nameOrKey);
+    }
+
+    /**
+     * Parse a world name into a {@link WorldKeyOrName} instance.
+     * <p>
+     * This will attempt to create a usable {@link NamespacedKey} from the given name using
+     * {@link NamespacedKey#minecraft(String)}. If parsing fails, a failure {@link Attempt} will be
+     * returned describing an invalid world name.
+     *
+     * @param name The world name to parse
+     * @return An {@link Attempt} containing a {@link WorldKeyOrName.Name} on success or a
+     * {@link WorldKeyParseFailReason#INVALID_WORLD_NAME} failure on error
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static Attempt<WorldKeyOrName, WorldKeyParseFailReason> parseName(@NotNull String name) {
+        return Try.of(() -> NamespacedKey.minecraft(mapWorldNameToMinecraftKey(name)))
+                .map(usableKey -> Attempt.<WorldKeyOrName, WorldKeyParseFailReason>success(new Name(name, usableKey)))
+                .recover(throwable -> Attempt.failure(WorldKeyParseFailReason.INVALID_WORLD_NAME,
+                        MessageReplacement.Replace.WORLD.with(name)))
+                .getOrElse(() -> Attempt.failure(WorldKeyParseFailReason.INVALID_WORLD_NAME,
+                        MessageReplacement.Replace.WORLD.with(name)));
+    }
+
+    private static String mapWorldNameToMinecraftKey(@NotNull String nameOrKey) {
+        String defaultLevelName = getMostAccurateLevelName();
+        String lowerCaseName = nameOrKey.toLowerCase(Locale.ROOT);
+        if (defaultLevelName.equalsIgnoreCase(lowerCaseName)) {
+            lowerCaseName = DEFAULT_OVERWORLD_KEY;
+        } else if (DimensionFinder.DEFAULT_NETHER_FORMAT.replaceOverworld(defaultLevelName).equalsIgnoreCase(lowerCaseName)) {
+            lowerCaseName = DEFAULT_NETHER_KEY;
+        } else if (DimensionFinder.DEFAULT_END_FORMAT.replaceOverworld(defaultLevelName).equalsIgnoreCase(lowerCaseName)) {
+            lowerCaseName = DEFAULT_END_KEY;
+        }
+        return lowerCaseName;
+    }
+
+    /**
+     * Parse a namespaced key string into a {@link WorldKeyOrName} instance.
+     *
+     * @param nameOrKey The namespaced key string to parse (e.g. "minecraft:world")
+     * @return An {@link Attempt} containing a {@link WorldKeyOrName.Key} on success or a
+     * {@link WorldKeyParseFailReason#INVALID_NAMESPACED_KEY} failure on error
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static Attempt<WorldKeyOrName, WorldKeyParseFailReason> parseKey(@NotNull String nameOrKey) {
+        return Option.of(NamespacedKey.fromString(nameOrKey))
+                .filter(Objects::nonNull)
+                .map(key -> Attempt.<WorldKeyOrName, WorldKeyParseFailReason>success(new Key(key, usableNameFromKey(key))))
+                .getOrElse(() -> Attempt.failure(WorldKeyParseFailReason.INVALID_NAMESPACED_KEY,
+                        MessageReplacement.Replace.NAMESPACE.with(nameOrKey)));
+    }
+
+    /**
+     * Create a {@link WorldKeyOrName} representing a namespaced key.
+     *
+     * @param key The {@link NamespacedKey} to wrap
+     * @return A {@link WorldKeyOrName} containing the provided key
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static WorldKeyOrName parseKey(@NotNull NamespacedKey key) {
+        return new Key(key,  usableNameFromKey(key));
+    }
+
+    private static String usableNameFromKey(@NotNull NamespacedKey key) {
+        return key.getNamespace().equals(NamespacedKey.MINECRAFT)
+                ? mapMinecraftKeyToWorldName(key)
+                : mapCustomKeyToWorldName(key);
+    }
+
+    private static String mapMinecraftKeyToWorldName(@NotNull NamespacedKey key) {
+        String defaultLevelName = getMostAccurateLevelName();
+        return switch (key.getKey()) {
+            case DEFAULT_OVERWORLD_KEY -> defaultLevelName;
+            case DEFAULT_NETHER_KEY -> DimensionFinder.DEFAULT_NETHER_FORMAT.replaceOverworld(defaultLevelName);
+            case DEFAULT_END_KEY -> DimensionFinder.DEFAULT_END_FORMAT.replaceOverworld(defaultLevelName);
+            default -> key.getKey();
+        };
+    }
+
+    private static String mapCustomKeyToWorldName(@NotNull NamespacedKey key) {
+        return key.getNamespace() + "_" + key.getKey();
+    }
+
+    private static String getMostAccurateLevelName() {
+        return UnsafeValuesCompatibility.getMainLevelName()
+                .orElse(ServerProperties::getStaticLevelName)
+                .getOrElse("world"); // Worse case assume its world
+    }
+
+    /**
+     * Returns true if this instance represents a world name (not a namespaced key).
+     *
+     * @return true if this is a name variant
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public abstract boolean isName();
+
+    /**
+     * Returns true if this instance represents a namespaced key (not a world name).
+     *
+     * @return true if this is a key variant
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public abstract boolean isKey();
+
+    /**
+     * Get the underlying {@link NamespacedKey} if this instance is a key variant.
+     *
+     * @return An {@link Option} containing the key when present, otherwise {@link Option#none()}
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public abstract @NotNull Option<NamespacedKey> getKey();
+
+    /**
+     * Get the underlying world name if this instance is a name variant.
+     *
+     * @return An {@link Option} containing the name when present, otherwise {@link Option#none()}
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public abstract @NotNull Option<String> getName();
+
+    /**
+     * Represent this value as an {@link Either} where the left side is the {@link NamespacedKey}
+     * and the right side is the world name.
+     *
+     * @return An {@link Either} containing either the key (left) or the name (right)
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public abstract @NotNull Either<NamespacedKey, String> asEither();
+
+    /**
+     * Get a usable {@link NamespacedKey} for this instance.
+     * <p>
+     * If this instance is a key variant, the underlying key is returned. If it is a name variant,
+     * an implementation-provided usable key (derived from the name) is returned.
+     *
+     * @return A non-null {@link NamespacedKey} that can be used where a key is required
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public abstract @NotNull NamespacedKey usableKey();
+
+    /**
+     * Get a usable name for this instance.
+     * <p>
+     * If this instance is a name variant, the underlying name is returned. If it is a key variant,
+     * a reasonable string representation derived from the key is returned.
+     *
+     * @return A non-null {@link String} representing a usable name
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public abstract @NotNull String usableName();
+
+    /**
+     * Serialize this instance to a string form suitable for storage or comparison.
+     *
+     * @return The serialized representation of this value
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public abstract @NotNull String serialise();
+
+    /**
+     * Sorts the instances based on their serialized form, which ensures that keys and names are sorted in an
+     * alphabetical manner by default.
+     *
+     * @param o the object to be compared.
+     * @return a negative integer, zero, or a positive integer as this object is less than, equal to, or greater than the specified object.
+     */
+    @Override
+    public int compareTo(WorldKeyOrName o) {
+        return serialise().compareTo(o.serialise());
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public @Nullable Message getLocalizableMessage() {
+        return Message.of(serialise());
+    }
+
+    public static final class Key extends WorldKeyOrName {
+
+        private final NamespacedKey key;
+        private final String usableName;
+
+        private Key(@NotNull NamespacedKey key, @NotNull String usableName) {
+            this.key = key;
+            this.usableName = usableName;
+        }
+
+        @Override
+        public boolean isName() {
+            return false;
+        }
+
+        @Override
+        public boolean isKey() {
+            return true;
+        }
+
+        @Override
+        public @NotNull Option<NamespacedKey> getKey() {
+            return Option.of(key);
+        }
+
+        @Override
+        public @NotNull Option<String> getName() {
+            return Option.none();
+        }
+
+        @Override
+        public @NotNull Either<NamespacedKey, String> asEither() {
+            return Either.left(key);
+        }
+
+        @Override
+        public @NotNull NamespacedKey usableKey() {
+            return key;
+        }
+
+        @Override
+        public @NotNull String usableName() {
+            return usableName;
+        }
+
+        @Override
+        public @NotNull String serialise() {
+            return key.toString();
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            if (o == null || getClass() != o.getClass()) return false;
+            Key key1 = (Key) o;
+            return Objects.equals(key, key1.key);
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hashCode(key);
+        }
+
+        @Override
+        public String toString() {
+            return "Key{" +
+                    "key=" + key +
+                    ", usableName='" + usableName + '\'' +
+                    '}';
+        }
+    }
+
+    public static final class Name extends WorldKeyOrName {
+
+        private final String name;
+        private final NamespacedKey usableKey;
+
+        private Name(String name, NamespacedKey usableKey) {
+            this.name = name;
+            this.usableKey = usableKey;
+        }
+
+        @Override
+        public boolean isName() {
+            return true;
+        }
+
+        @Override
+        public boolean isKey() {
+            return false;
+        }
+
+        @Override
+        public @NotNull Option<NamespacedKey> getKey() {
+            return Option.none();
+        }
+
+        @Override
+        public @NotNull Option<String> getName() {
+            return Option.of(name);
+        }
+
+        @Override
+        public @NotNull Either<NamespacedKey, String> asEither() {
+            return Either.right(name);
+        }
+
+        @Override
+        public @NotNull NamespacedKey usableKey() {
+            return usableKey;
+        }
+
+        @Override
+        public @NotNull String usableName() {
+            return name;
+        }
+
+        @Override
+        public @NotNull String serialise() {
+            return name;
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            if (o == null || getClass() != o.getClass()) return false;
+            Name name1 = (Name) o;
+            return Objects.equals(name, name1.name);
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(name);
+        }
+
+        @Override
+        public String toString() {
+            return "Name{" +
+                    "name='" + name + '\'' +
+                    ", usableKey=" + usableKey +
+                    '}';
+        }
+    }
+}

src/main/java/org/mvplugins/multiverse/core/world/key/WorldKeyParseFailReason.java

@@ -0,0 +1,64 @@
+package org.mvplugins.multiverse.core.world.key;
+
+import co.aikar.locales.MessageKey;
+import co.aikar.locales.MessageKeyProvider;
+import org.jetbrains.annotations.ApiStatus;
+import org.mvplugins.multiverse.core.locale.MVCorei18n;
+import org.mvplugins.multiverse.core.utils.result.FailureReason;
+
+/**
+ * Reasons why parsing a world key or name failed.
+ * <br />
+ * These values are returned by parsing utilities such as {@link org.mvplugins.multiverse.core.world.key.WorldKeyOrName#parse}
+ * to indicate the specific cause of failure so callers can present an appropriate localized message.
+ *
+ * @since 5.7
+ */
+@ApiStatus.AvailableSince("5.7")
+public enum WorldKeyParseFailReason implements FailureReason {
+    /**
+     * The provided input was null or empty.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    EMPTY(MVCorei18n.WORLDKEYPARSE_EMPTY),
+
+    /**
+     * The provided world name contains invalid characters or format.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    INVALID_WORLD_NAME(MVCorei18n.WORLDKEYPARSE_INVALIDWORLDNAME),
+
+    /**
+     * The provided string was intended to be a namespaced key but did not parse as a valid
+     * {@link org.bukkit.NamespacedKey} (malformed namespace/key or missing parts).
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    INVALID_NAMESPACED_KEY(MVCorei18n.WORLDKEYPARSE_INVALIDNAMESPACEDKEY),
+    ;
+
+    private final MessageKeyProvider message;
+
+    WorldKeyParseFailReason(MessageKeyProvider message) {
+        this.message = message;
+    }
+
+    /**
+     * Return the localized message key associated with this failure reason.
+     * <p>
+     * Implementations of {@link FailureReason} can use this to provide a user-facing localized
+     * message for the failure.
+     *
+     * @return The {@link MessageKey} that corresponds to this failure reason
+     * @since 5.7
+     */
+    @Override
+    public MessageKey getMessageKey() {
+        return message.getMessageKey();
+    }
+}

src/main/java/org/mvplugins/multiverse/core/world/options/CloneWorldOptions.java

@@ -1,7 +1,12 @@
 package org.mvplugins.multiverse.core.world.options;
 
+import io.vavr.control.Either;
+import org.bukkit.NamespacedKey;
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 import org.mvplugins.multiverse.core.world.LoadedMultiverseWorld;
+import org.mvplugins.multiverse.core.world.MultiverseWorld;
+import org.mvplugins.multiverse.core.world.key.WorldKeyOrName;
 
 /**
  * Options for customizing the cloning of a world.
@@ -9,36 +14,112 @@ import org.mvplugins.multiverse.core.world.LoadedMultiverseWorld;
 public final class CloneWorldOptions implements KeepWorldSettingsOptions {
 
     /**
-     * Creates a new {@link CloneWorldOptions} instance with the given world.
+     * Creates a new {@link CloneWorldOptions} instance with the given loaded world.
      *
-     * @param world         The world to clone.
+     * @param fromWorld     The loaded world to clone.
      * @param newWorldName  The name of the new world.
      * @return A new {@link CloneWorldOptions} instance.
+     *
+     * @deprecated Cloning can be done from unloaded worlds as well. Use {@link #fromTo(MultiverseWorld, String)} instead.
+     * To ensure you use the non-deprecated method, you need to downcast the loaded world to a {@link MultiverseWorld}
+     * before passing it in, for example: {@code CloneWorldOptions.fromTo((MultiverseWorld) loadedWorld, newWorldName)}
      */
-    public static CloneWorldOptions fromTo(LoadedMultiverseWorld world, String newWorldName) {
-        return new CloneWorldOptions(world, newWorldName);
+    @Deprecated(forRemoval = true, since = "5.6")
+    @ApiStatus.ScheduledForRemoval(inVersion = "6.0")
+    public static @NotNull CloneWorldOptions fromTo(@NotNull LoadedMultiverseWorld fromWorld, @NotNull String newWorldName) {
+        return fromTo((MultiverseWorld) fromWorld, newWorldName);
     }
 
-    private final LoadedMultiverseWorld world;
-    private final String newWorldName;
+    /**
+     * Creates a new {@link CloneWorldOptions} instance with the given world.
+     *
+     * @param fromWorld     The world to clone.
+     * @param newWorldName  The name of the new world.
+     * @return A new {@link CloneWorldOptions} instance.
+     *
+     * @since 5.6
+     */
+    @ApiStatus.AvailableSince("5.6")
+    public static @NotNull CloneWorldOptions fromTo(@NotNull MultiverseWorld fromWorld, @NotNull String newWorldName) {
+        return new CloneWorldOptions(fromWorld, Either.left(newWorldName));
+    }
+
+    /**
+     * Creates a new {@link CloneWorldOptions} instance with the given world and namespaced key.
+     *
+     * @param fromWorld The world to clone.
+     * @param key       The namespaced key for the new world.
+     * @return A new {@link CloneWorldOptions} instance.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static @NotNull CloneWorldOptions fromTo(@NotNull MultiverseWorld fromWorld, @NotNull NamespacedKey key) {
+        return new CloneWorldOptions(fromWorld, Either.right(WorldKeyOrName.parseKey(key)));
+    }
+
+    /**
+     * Creates a new {@link CloneWorldOptions} instance with the given world and world key or name.
+     *
+     * @param fromWorld The world to clone.
+     * @param keyOrName The key or name for the new world.
+     * @return A new {@link CloneWorldOptions} instance.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static @NotNull CloneWorldOptions fromTo(@NotNull MultiverseWorld fromWorld, @NotNull WorldKeyOrName keyOrName) {
+        return new CloneWorldOptions(fromWorld, Either.right(keyOrName));
+    }
+
+    private final MultiverseWorld fromWorld;
+    private final Either<String, WorldKeyOrName> newWorldKeyOrName;
     private boolean keepGameRule = true;
     private boolean keepWorldConfig = true;
     private boolean saveBukkitWorld = true;
 
     private boolean keepWorldBorder = true;
 
-    CloneWorldOptions(LoadedMultiverseWorld world, String newWorldName) {
-        this.world = world;
-        this.newWorldName = newWorldName;
+    CloneWorldOptions(MultiverseWorld fromWorld, Either<String, WorldKeyOrName> newWorldKeyOrName) {
+        this.fromWorld = fromWorld;
+        this.newWorldKeyOrName = newWorldKeyOrName;
     }
 
     /**
-     * Gets the world to clone.
+     * Gets the loaded world to clone.
      *
      * @return The world to clone.
+     *
+     * @deprecated Cloning can be done from unloaded worlds as well. Use {@link #fromWorld()} instead.
      */
+    @Deprecated(forRemoval = true, since = "5.6")
+    @ApiStatus.ScheduledForRemoval(inVersion = "6.0")
     public LoadedMultiverseWorld world() {
-        return world;
+        return fromWorld.asLoadedWorld().getOrNull();
+    }
+
+    /**
+     * Gets the loaded world to clone.
+     *
+     * @return The world to clone.
+     *
+     * @since 5.6
+     */
+    @ApiStatus.AvailableSince("5.6")
+    public @NotNull MultiverseWorld fromWorld() {
+        return fromWorld;
+    }
+
+    /**
+     * Gets the new world key or name, either unparsed as string or the {@link WorldKeyOrName} instance.
+     *
+     * @return The new world key or name.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public @NotNull Either<String, WorldKeyOrName> newWorldKeyOrName() {
+        return newWorldKeyOrName;
     }
 
     /**
@@ -46,8 +127,10 @@ public final class CloneWorldOptions implements KeepWorldSettingsOptions {
      *
      * @return The name of the new world.
      */
-    public String newWorldName() {
-        return newWorldName;
+    @Deprecated(forRemoval = true, since = "5.7")
+    @ApiStatus.ScheduledForRemoval(inVersion = "6.0")
+    public @NotNull String newWorldName() {
+        return newWorldKeyOrName.fold(name -> name, WorldKeyOrName::usableName);
     }
 
     /**

src/main/java/org/mvplugins/multiverse/core/world/options/CreateWorldOptions.java

@@ -1,10 +1,21 @@
 package org.mvplugins.multiverse.core.world.options;
 
 import co.aikar.commands.ACFUtil;
+import io.vavr.control.Either;
+import io.vavr.control.Option;
+import org.bukkit.NamespacedKey;
 import org.bukkit.World;
 import org.bukkit.WorldType;
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
+import org.jetbrains.annotations.UnmodifiableView;
+import org.mvplugins.multiverse.core.utils.position.EntityPosition;
+import org.mvplugins.multiverse.core.world.key.WorldKeyOrName;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
 
 /**
  * Options for customizing the creation of a new world.
@@ -18,12 +29,43 @@ public final class CreateWorldOptions {
      * @return A new {@link CreateWorldOptions} instance.
      */
     public static @NotNull CreateWorldOptions worldName(@NotNull String worldName) {
-        return new CreateWorldOptions(worldName);
+        return new CreateWorldOptions(Either.left(worldName));
     }
 
-    private final String worldName;
+    /**
+     * Creates a new {@link CreateWorldOptions} instance with the given namespaced key. Note that creating world with
+     * namespace requires PaperMC. This will not work on Spigot.
+     *
+     * @param key The namespaced key for the world to create.
+     * @return A new {@link CreateWorldOptions} instance.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static @NotNull CreateWorldOptions worldKey(@NotNull NamespacedKey key) {
+        return new CreateWorldOptions(Either.right(WorldKeyOrName.parseKey(key)));
+    }
+
+    /**
+     * Creates a new {@link CreateWorldOptions} instance with the given world key or name. Note that creating world with
+     * namespace requires PaperMC. WorldKeyOrName parsed as namespaced key (i.e. {@link WorldKeyOrName#isKey()} is true)
+     * will not work on Spigot.
+     *
+     * @param keyOrName The key or name for the world to create.
+     * @return A new {@link CreateWorldOptions} instance.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static @NotNull CreateWorldOptions worldKeyOrName(@NotNull WorldKeyOrName keyOrName) {
+        return new CreateWorldOptions(Either.right(keyOrName));
+    }
+
+    private final Either<String, WorldKeyOrName> keyOrName;
     private String biome = "";
+    private boolean bonusChest = false;
     private World.Environment environment = World.Environment.NORMAL;
+    private EntityPosition forcedSpawnPosition = null;
     private boolean generateStructures = true;
     private String generator = null;
     private String generatorSettings = "";
@@ -31,24 +73,38 @@ public final class CreateWorldOptions {
     private boolean useSpawnAdjust = true;
     private WorldType worldType = WorldType.NORMAL;
     private boolean doFolderCheck = true;
+    private final Map<String, String> worldPropertyStrings = new HashMap<>();
 
     /**
-     * Creates a new {@link CreateWorldOptions} instance with the given world name.
+     * Creates a new {@link CreateWorldOptions} instance with either a world name or world key or name.
      *
-     * @param worldName The name of the world to create.
+     * @param keyOrName Either the world name or the world key/name instance.
      */
-    CreateWorldOptions(@NotNull String worldName) {
-        this.worldName = worldName;
+    CreateWorldOptions(@NotNull Either<String, WorldKeyOrName> keyOrName) {
+        this.keyOrName = keyOrName;
         this.seed = ACFUtil.RANDOM.nextLong();
     }
 
+    /**
+     * Gets the new world key or name, either unparsed as string or the {@link WorldKeyOrName} instance.
+     *
+     * @return The new world key or name.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public @NotNull Either<String, WorldKeyOrName> keyOrName() {
+        return keyOrName;
+    }
+
     /**
      * Gets the name of the world to create.
      *
      * @return The name of the world to create.
      */
+    @Deprecated(forRemoval = true, since = "5.7")
     public @NotNull String worldName() {
-        return worldName;
+        return keyOrName.fold(name -> name ,WorldKeyOrName::usableName);
     }
 
     /**
@@ -73,6 +129,32 @@ public final class CreateWorldOptions {
         return biome;
     }
 
+    /**
+     * Sets whether bonus chest should generate at spawn upon world creation.
+     * <br />
+     * This feature only works on PaperMC 1.21.5+
+     *
+     * @param bonusChest Whether bonus chest should generate at spawn upon world creation.
+     * @return This {@link CreateWorldOptions} instance.
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public @NotNull CreateWorldOptions bonusChest(boolean bonusChest) {
+        this.bonusChest = bonusChest;
+        return this;
+    }
+
+    /**
+     * Gets whether bonus chest should generate at spawn upon world creation.
+     * <br />
+     * This feature only works on PaperMC 1.21.5+
+     *
+     * @return true if bonus chest should generate, else false.
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public boolean bonusChest() {
+        return bonusChest;
+    }
+
     /**
      * Sets the environment of the world to create.
      *
@@ -93,6 +175,37 @@ public final class CreateWorldOptions {
         return environment;
     }
 
+    /**
+     * Sets the forced spawn position of the world to apply. This may be null, in which case the spawn position will
+     * be determined by the default generator. Setting spawn position and {@link #useSpawnAdjust(boolean)} to false
+     * will improve world creation speed on PaperMC as chunks will not be loaded to search for spawn point.
+     * <br />
+     * This feature only works on PaperMC 26.1+
+     *
+     * @param forcedSpawnPosition   The forced spawn position of the world to create.
+     * @return This {@link CreateWorldOptions} instance.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public @NotNull CreateWorldOptions forcedSpawnPosition(@Nullable EntityPosition forcedSpawnPosition) {
+        this.forcedSpawnPosition = forcedSpawnPosition;
+        return this;
+    }
+
+    /**
+     * Sets the forced spawn position of the world to apply. This may be null, in which case the spawn position will
+     * be determined by the default generator.
+     * <br />
+     * This feature only works on PaperMC 26.1+
+     *
+     * @return The force spawn position to apply if available.
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public @NotNull Option<EntityPosition> forcedSpawnPosition() {
+        return Option.of(this.forcedSpawnPosition);
+    }
+
     /**
      * Sets whether structures such as NPC villages should be generated.
      *
@@ -260,4 +373,46 @@ public final class CreateWorldOptions {
     public boolean doFolderCheck() {
         return doFolderCheck;
     }
+
+    /**
+     * Sets a world property string key-value pair. Overwrites any existing key.
+     *
+     * @param key   The key of the world property string.
+     * @param value The value of the world property string.
+     * @return This {@link CreateWorldOptions} instance.
+     *
+     * @since 5.5
+     */
+    @ApiStatus.AvailableSince("5.5")
+    public @NotNull CreateWorldOptions worldPropertyString(@NotNull String key, @Nullable String value) {
+        this.worldPropertyStrings.put(key, value);
+        return this;
+    }
+
+    /**
+     * Sets multiple world property string key-value pairs. Overwrites any existing keys.
+     *
+     * @param worldProperties   A map of world property string key-value pairs.
+     * @return This {@link CreateWorldOptions} instance.
+     *
+     * @since 5.5
+     */
+    @ApiStatus.AvailableSince("5.5")
+    public @NotNull CreateWorldOptions worldPropertyStrings(@NotNull Map<@NotNull String, @Nullable String> worldProperties) {
+        this.worldPropertyStrings.putAll(worldProperties);
+        return this;
+    }
+
+    /**
+     * Gets an unmodifiable view of the world property strings. Use {@link #worldPropertyString(String, String)} and
+     * {@link #worldPropertyStrings(Map)} to modify the world property strings.
+     *
+     * @return An unmodifiable view of the world property strings.
+     *
+     * @since 5.5
+     */
+    @ApiStatus.AvailableSince("5.5")
+    public @UnmodifiableView @NotNull Map<String, String> worldPropertyStrings() {
+        return Collections.unmodifiableMap(worldPropertyStrings);
+    }
 }

src/main/java/org/mvplugins/multiverse/core/world/options/ImportWorldOptions.java

@@ -1,9 +1,12 @@
 package org.mvplugins.multiverse.core.world.options;
 
+import io.vavr.control.Either;
+import org.bukkit.NamespacedKey;
 import org.bukkit.World;
 import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
+import org.mvplugins.multiverse.core.world.key.WorldKeyOrName;
 
 /**
  * Options for customizing the import of a new world.
@@ -17,18 +20,65 @@ public final class ImportWorldOptions {
      * @return A new {@link ImportWorldOptions} instance.
      */
     public static @NotNull ImportWorldOptions worldName(@NotNull String worldName) {
-        return new ImportWorldOptions(worldName);
+        return new ImportWorldOptions(Either.left(worldName));
     }
 
-    private final String worldName;
+    /**
+     * Creates a new {@link ImportWorldOptions} instance with the given namespaced key. Note that importing world with
+     * namespace requires PaperMC. This will not work on Spigot.
+     *
+     * @param key The namespaced key for the world to import.
+     * @return A new {@link ImportWorldOptions} instance.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static @NotNull ImportWorldOptions worldKey(@NotNull NamespacedKey key) {
+        return new ImportWorldOptions(Either.right(WorldKeyOrName.parseKey(key)));
+    }
+
+    /**
+     * Creates a new {@link ImportWorldOptions} instance with the given world key or name. Note that importing world with
+     * namespace requires PaperMC. WorldKeyOrName parsed as namespaced key (i.e. {@link WorldKeyOrName#isKey()} is true)
+     * will not work on Spigot.
+     *
+     * @param keyOrName The key or name for the world to import.
+     * @return A new {@link ImportWorldOptions} instance.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public static @NotNull ImportWorldOptions worldKeyOrName(@NotNull WorldKeyOrName keyOrName) {
+        return new ImportWorldOptions(Either.right(keyOrName));
+    }
+
+    private final Either<String, WorldKeyOrName> keyOrName;
     private String biome = "";
     private World.Environment environment = World.Environment.NORMAL;
     private String generator = null;
+    private String generatorSettings = "";
     private boolean useSpawnAdjust = true;
     private boolean doFolderCheck = true;
 
-    ImportWorldOptions(String worldName) {
-        this.worldName = worldName;
+    /**
+     * Creates a new {@link ImportWorldOptions} instance with either a world name or world key or name.
+     *
+     * @param keyOrName Either the world name or the world key/name instance.
+     */
+    ImportWorldOptions(Either<String, WorldKeyOrName> keyOrName) {
+        this.keyOrName = keyOrName;
+    }
+
+    /**
+     * Gets the new world key or name, either unparsed as string or the {@link WorldKeyOrName} instance.
+     *
+     * @return The new world key or name.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public @NotNull Either<String, WorldKeyOrName> keyOrName() {
+        return keyOrName;
     }
 
     /**
@@ -36,8 +86,10 @@ public final class ImportWorldOptions {
      *
      * @return The name of the world to create.
      */
+    @Deprecated(forRemoval = true, since = "5.7")
+    @ApiStatus.ScheduledForRemoval(inVersion = "6.0")
     public @NotNull String worldName() {
-        return worldName;
+        return keyOrName.fold(name -> name ,WorldKeyOrName::usableName);
     }
 
     /**
@@ -102,6 +154,32 @@ public final class ImportWorldOptions {
         return generator;
     }
 
+    /**
+     * Sets the custom generator settings string used when creating the world.
+     *
+     * @param generatorSettingsInput The custom generator settings string, or null to use the default settings.
+     * @return This {@link ImportWorldOptions} instance.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public @NotNull ImportWorldOptions generatorSettings(@NotNull String generatorSettingsInput) {
+        this.generatorSettings = generatorSettingsInput;
+        return this;
+    }
+
+    /**
+     * Gets the custom generator settings string used when creating the world.
+     *
+     * @return The custom generator settings string, or null if none was set.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    public @NotNull String generatorSettings() {
+        return generatorSettings;
+    }
+
     /**
      * Sets whether multiverse will search for a safe spawn location.
      *

src/main/java/org/mvplugins/multiverse/core/world/reasons/CloneFailureReason.java

@@ -3,6 +3,7 @@ package org.mvplugins.multiverse.core.world.reasons;
 import co.aikar.locales.MessageKey;
 import co.aikar.locales.MessageKeyProvider;
 
+import org.jetbrains.annotations.ApiStatus;
 import org.mvplugins.multiverse.core.locale.MVCorei18n;
 import org.mvplugins.multiverse.core.utils.result.FailureReason;
 
@@ -15,6 +16,15 @@ public enum CloneFailureReason implements FailureReason {
      */
     INVALID_WORLDNAME(MVCorei18n.CLONEWORLD_INVALIDWORLDNAME),
 
+    /**
+     * The server software does not support create worlds using namespaced key. Only legacy world name is supported.
+     * Generally this will only be an issue on Spigot servers.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    NAMESPACEDKEY_UNSUPPORTED(MVCorei18n.WORLDKEYPARSE_NAMESPACEDKEYUNSUPPORTED),
+
     /**
      * The target new world folder already exists.
      */
@@ -30,6 +40,14 @@ public enum CloneFailureReason implements FailureReason {
      */
     WORLD_EXIST_LOADED(MVCorei18n.CLONEWORLD_WORLDEXISTLOADED),
 
+    /**
+     * The source world folder is invalid.
+     *
+     * @since 5.6
+     */
+    @ApiStatus.AvailableSince("5.6")
+    FROM_WORLD_FOLDER_INVALID(MVCorei18n.CLONEWORLD_FROMWORLDFOLDERINVALID),
+
     /**
      * Failed to copy the world folder contents.
      */

src/main/java/org/mvplugins/multiverse/core/world/reasons/CreateFailureReason.java

@@ -3,6 +3,7 @@ package org.mvplugins.multiverse.core.world.reasons;
 import co.aikar.locales.MessageKey;
 import co.aikar.locales.MessageKeyProvider;
 
+import org.jetbrains.annotations.ApiStatus;
 import org.mvplugins.multiverse.core.locale.MVCorei18n;
 import org.mvplugins.multiverse.core.utils.result.FailureReason;
 
@@ -15,6 +16,15 @@ public enum CreateFailureReason implements FailureReason {
      */
     INVALID_WORLDNAME(MVCorei18n.CREATEWORLD_INVALIDWORLDNAME),
 
+    /**
+     * The server software does not support create worlds using namespaced key. Only legacy world name is supported.
+     * Generally this will only be an issue on Spigot servers.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    NAMESPACEDKEY_UNSUPPORTED(MVCorei18n.WORLDKEYPARSE_NAMESPACEDKEYUNSUPPORTED),
+
     /**
      * The target new world folder already exists.
      */

src/main/java/org/mvplugins/multiverse/core/world/reasons/ImportFailureReason.java

@@ -16,6 +16,15 @@ public enum ImportFailureReason implements FailureReason {
      */
     INVALID_WORLDNAME(MVCorei18n.IMPORTWORLD_INVALIDWORLDNAME),
 
+    /**
+     * The server software does not support create worlds using namespaced key. Only legacy world name is supported.
+     * Generally this will only be an issue on Spigot servers.
+     *
+     * @since 5.7
+     */
+    @ApiStatus.AvailableSince("5.7")
+    NAMESPACEDKEY_UNSUPPORTED(MVCorei18n.WORLDKEYPARSE_NAMESPACEDKEYUNSUPPORTED),
+
     /**
      * The world folder is invalid.
      */

src/main/java/org/mvplugins/multiverse/core/world/reasons/LoadFailureReason.java

@@ -47,6 +47,12 @@ public enum LoadFailureReason implements FailureReason {
     @ApiStatus.AvailableSince("5.2")
     BUKKIT_ENVIRONMENT_MISMATCH(MVCorei18n.LOADWORLD_BUKKITENVIRONMENTMISMATCH),
 
+    /**
+     * The mv world's namespace key does not match the loaded Bukkit world's key.
+     */
+    @ApiStatus.AvailableSince("5.7")
+    BUKKIT_NAMESPACED_KEY_MISMATCH(MVCorei18n.LOADWORLD_BUKKITNAMESPACEDKEYMISMATCH),
+
     /**
      * Bukkit API failed to create the world.
      */

src/main/resources/multiverse-core_en.properties

@@ -72,7 +72,8 @@ mv-core.delete.success=&aWorld '{world}' deleted!
 
 # /mv dumps
 mv-core.dumps.description=Dumps version info to the console or paste services
-mv-core.dumps.url.list={service} : {link}
+mv-core.dumps.starting=Gathering logs and debug info...
+mv-core.dumps.url.list=&aUploaded with {service} backend: &6{link}
 
 # /mv gamerule set
 mv-core.gamerule.set.description=Changes a gamerule in one or more worlds.
@@ -127,6 +128,24 @@ mv-core.load.world.description=Name of world you want to load.
 mv-core.load.loading=Loading world '{world}'...
 mv-core.load.success=&aWorld '{world}' loaded!
 
+# /mv meta info
+mv-core.meta.info.description=Shows all metadata for a world.
+mv-core.meta.info.world.description=The world to show metadata for.
+mv-core.meta.info.header=&a&l---- World Metadata: &f&l{world}&a&l ----
+mv-core.meta.info.nocontent=&cNo metadata found for world '{world}'. You can set metadata with '&6/mv meta modify {world} set <key> <value>&c' command!
+
+# /mv meta modify
+mv-core.meta.modify.description=Modifies a metadata of a given world.
+mv-core.meta.modify.world.description=Name of world you want to modify metadata of.
+mv-core.meta.modify.action.description=Action to perform on the metadata. Can be 'set', 'remove', or 'reset'.
+mv-core.meta.modify.key.description=Metadata key to modify.
+mv-core.meta.modify.value.description=Value to set the metadata to. Only used when action is 'set'.
+mv-core.meta.modify.set.success=&aSuccessfully set metadata key '&9{key}&a' to '&9{value}&a' for world &9{world}&a.
+mv-core.meta.modify.set.failure=&cFailed to set metadata key '&9{key}&c' to '&9{value}&c' for world &9{world}&c.\n&c{error}
+mv-core.meta.modify.remove.success=&aSuccessfully removed metadata key '&9{key}&a' for world &9{world}&a.
+mv-core.meta.modify.remove.failure=&cFailed to remove metadata key '&9{key}&c' for world &9{world}&c.\n&c{error}
+mv-core.meta.modify.invalidaction=&cInvalid action '&6{action}&c'! Valid actions are 'set' and 'remove' only.
+
 # /mv modify
 mv-core.modify.description=Modifies a world property of a given world.
 mv-core.modify.world.description=Name of world you want to modify.
@@ -221,15 +240,17 @@ mv-core.worldborder.damagebuffer.success=&rSet the world border damage buffer to
 mv-core.worldborder.get.size=&rThe world border is currently {size} block(s) wide for world '&6{world}&r'.
 
 mv-core.worldborder.set.nothingchanged=&cNothing changed. The world border is already that size for world '&6{world}&c'.
-mv-core.worldborder.set.immediate=&rSet the world border to {size} block(s) wide for world '&6{world}&r'.
-mv-core.worldborder.set.shrinking=&rShrinking the world border to {size} block(s) wide over {time} second(s) for world '&6{world}&r'.
-mv-core.worldborder.set.growing=&rGrowing the world border to {size} block(s) wide over {time} second(s) for world '&6{world}&r'.
+mv-core.worldborder.set.immediate=&fSet the world border to &6{size}&f block(s) wide for world '&6{world}&f'.
+mv-core.worldborder.set.shrinking=&fShrinking the world border to &6{size}&f block(s) wide over &6{time}&f second(s) for world '&6{world}&f'.
+mv-core.worldborder.set.growing=&fGrowing the world border to &6{size} block(s) wide over &6{time}&f second(s) for world '&6{world}&f'.
 
 mv-core.worldborder.warningdistance.nothingchanged=&cNothing changed. The world border warning is already that distance for world '&6{world}&c'.
-mv-core.worldborder.warningdistance.success=&rSet the world border warning distance to {distance} block(s) for world '&6{world}&r'.
+mv-core.worldborder.warningdistance.success=&fSet the world border warning distance to &6{distance}&f block(s) for world '&6{world}&f'.
 
 mv-core.worldborder.warningtime.nothingchanged=&cNothing changed. The world border warning is already that amount of time for world '&6{world}&c'.
-mv-core.worldborder.warningtime.success=&rSet the world border warning time to {time} second(s) for world '&6{world}&r'.
+mv-core.worldborder.warningtime.success=&fSet the world border warning time to &6{time}&f second(s) for world '&6{world}&f'.
+
+mv-core.worldborder.roundoff.warning=&cYour server version does not support setting time in ticks. Hence, it will be rounded to the nearest second from &6{fromTime}&c second(s) to &6{toTime}&c second(s).
 
 # commands error
 mv-core.commands.error.playersonly=&cThis command can only be used by players
@@ -259,6 +280,10 @@ mv-core.destination.shared.failurereason.invalidnumberformat=&cInvalid destinati
 mv-core.destination.shared.failurereason.worldnotfound=&cWorld '&6{world}&c' does not exist or is not loaded!
 mv-core.destination.parse.failurereason.invaliddestinationid=Invalid destination id: {id}. Valid destination ids are: {ids}
 
+# portal form disabled
+mv-core.portalform.disabled.end=&cCreating end portals is disabled in this world.
+mv-core.portalform.disabled.nether=&cCreating nether portals is disabled in this world.
+
 # teleport failure reason
 mv-core.teleportfailurereason.null.destination=The destination is invalid!
 mv-core.teleportfailurereason.null.location=The location is invalid!
@@ -273,6 +298,7 @@ mv-core.cloneworld.invalidworldname=World '{world}' contains invalid characters!
 mv-core.cloneworld.worldexistfolder=World '{world}' exists in server folders! You need to delete it first before cloning.
 mv-core.cloneworld.worldexistunloaded=World '{world}' already exists and it's unloaded! You need to delete it first before cloning.
 mv-core.cloneworld.worldexistloaded=World '{world}' already exists! You need to delete it first before cloning.
+mv-core.cloneworld.fromworldfolderinvalid=Source world '{world}' folder contents does not seem to be a valid world! Make sure it contains the correct world structure of data and region folders.
 mv-core.cloneworld.copyfailed=Failed to copy world to '{world}': {error}\n&fSee console for more details.
 
 mv-core.createworld.invalidworldname=World '{world}' contains invalid characters!
@@ -288,14 +314,16 @@ mv-core.deleteworld.failedtodeletefolder=Failed to delete world folder '{world}'
 mv-core.importworld.invalidworldname=World '{world}' contains invalid characters!
 mv-core.importworld.worldexistunloaded=World '{world}' already exists, but it's not loaded!&f Type '&a/mv load {world}&f' if you wish to load it.
 mv-core.importworld.worldexistloaded=World '{world}' already exists!
-mv-core.importworld.worldfolderinvalid=World '{world}' folder contents does not seem to be a valid world!\n&cIf the server software does something different with world folders, or you are very certain the world is valid, use '&3--skip-folder-check&c' flag.
+mv-core.importworld.worldfolderinvalid=World '{world}' folder contents does not seem to be a valid world! Make sure it contains the correct world structure of data and region folders.\n&cIf the server software does something different with world folders, or you are very certain the world is valid, use '&3--skip-folder-check&c' flag.
 mv-core.importworld.bukkitenvironmentmismatch=Environment mismatch detected!&f The world '{world}' is already loaded with environment '{bukkitEnvironment}', but Multiverse is trying to import it with environment '{mvEnvironment}'.
+mv-core.importworld.bukkitnamespacemismatch=Namespace mismatch detected!&f The world '{world}' is already loaded with namespace '{bukkitNamespace}', but Multiverse is trying to import it with namespace '{mvNamespace}'.
 
 mv-core.loadworld.worldalreadyloading=World '{world}' is already loading! Please wait...
 mv-core.loadworld.worldnonexistent=World '{world}' not found! Use '&a/mv create {world} <environment>&f' to create it.
 mv-core.loadworld.worldexistfolder=World '{world}' exists in server folders, but it's not known to Multiverse!&f Type '&a/mv import {world} <environment>&f' if you wish to import it.
 mv-core.loadworld.worldexistloaded=World '{world}' is already loaded!
 mv-core.loadworld.bukkitenvironmentmismatch=Environment mismatch detected!&f The world '{world}' is already loaded with environment '{bukkitEnvironment}', but Multiverse is trying to load it with environment '{mvEnvironment}'.
+mv-core.loadworld.bukkitnamespacemismatch=Namespace mismatch detected!&f The world '{world}' is already loaded with namespace '{bukkitNamespace}', but Multiverse is trying to load it with namespace '{mvNamespace}'.
 
 mv-core.removeworld.worldnonexistent=World '{world}' not found!
 
@@ -332,6 +360,12 @@ mv-core.exception.positionparse.invaliddirection=&cInvalid direction string form
 mv-core.exception.positionparse.invalidcoordinates=&cInvalid coordinates format: {format}. Expected format: <x>,<y>,<z>
 mv-core.exception.positionparse.invalidnumber=&cInvalid number format: {number}. Expects a numeric value.
 
+# world key parse failures
+mv-core.worldkeyparse.empty==&cWorld name/key cannot be empty!
+mv-core.worldkeyparse.invalidworldname=&cWorld name '{world}' contains invalid characters. The allowed characters are: a-z, A-Z, 0-9, _, -, and . (dot)
+mv-core.worldkeyparse.invalidnamespacedkey=&cNamespaced key '{namespace}' contains invalid characters. Expected a namespaced key format is 'namespace:key'. The allowed characters are: a-z (only lowercase), 0-9, _, -, and . (dot), with a single ':'.
+mv-core.worldkeyparse.namespacedkeyunsupported=&cYour server software does not support namespaced keys, but the world name '{namespace}' is in namespaced key format! Please change the world key to the legacy format without ':', or switch to PaperMC that supports namespaced keys.
+
 # generic
 mv-core.generic.success=Success!
 mv-core.generic.failure=Failed!

src/main/resources/multiverse-core_zh.properties

@@ -1,6 +1,6 @@
 # configuration
-mv-core.config.save.failed=保存 Multiverse-Core 的 config.yml 文件失败，所有操作都将是临时的！
-mv-core.config.node.notfound=在配置文件中无法找到节点: {node}
+mv-core.config.save.failed=保存 Multiverse-Core 的 config.yml 文件失败，所有修改都将是临时的！
+mv-core.config.node.notfound=在配置文件中无法找到节点： {node}
 
 # /mv check
 mv-core.check.description=检查某位玩家是否可以将自己传送至某个地方。
@@ -8,7 +8,7 @@ mv-core.check.player.description=要检查的玩家。
 mv-core.check.destination.description=目标的地址，例如某个世界的名字。
 mv-core.check.haspermission=&a{player} 可以传送至 {destination}
 mv-core.check.nopermission=&c{player} 不能传送至 {destination}
-mv-core.check.location=目标的地址是: &f{location}
+mv-core.check.location=目标的地址是： &f{location}
 
 # /mv clone
 mv-core.clone.description=复制一个世界。
@@ -19,7 +19,7 @@ mv-core.clone.success=&a已将世界复制到 '{world}'！
 
 # /mv config
 mv-core.config.description=查看或设置某个配置的值。
-mv-core.config.name.description=需要查看或设置的配置。
+mv-core.config.name.description=需要设置或查看的配置。
 mv-core.config.value.description=需要设置的值。如果没有指定，将显示当前配置的值。
 mv-core.config.show.success=&a配置 '&6{name}&a' 已被设置为 '&6{value}&a'。
 mv-core.config.show.error=&c获取配置 '&6{name}&c' 的值失败。\n&c{error}
@@ -30,29 +30,29 @@ mv-core.config.set.error=&c将配置 '&6{name}&c' 设置为 '&6{value}&c' 失败
 mv-core.confirm.description=在执行危险的指令前再一次进行确认。
 
 # /mv coordinates
-mv-core.coordinates.description=发送你的坐标信息
+mv-core.coordinates.description=直接发送你的坐标
 mv-core.coordinates.info.title=&b--- 位置信息 ---
-mv-core.coordinates.info.world=&b世界: &f{world}
-mv-core.coordinates.info.alias=&b别名: &f{alias}
-mv-core.coordinates.info.worldScale=&b世界尺度: &f{scale}
-mv-core.coordinates.info.coordinates=&b坐标: &f{coordinates}
-mv-core.coordinates.info.direction=&b方向: &f{direction}
+mv-core.coordinates.info.world=&b世界： &f{world}
+mv-core.coordinates.info.alias=&b别名： &f{alias}
+mv-core.coordinates.info.worldScale=&b世界比例： &f{scale}
+mv-core.coordinates.info.coordinates=&b坐标： &f{coordinates}
+mv-core.coordinates.info.direction=&b方向： &f{direction}
 
 # /mv create
 mv-core.create.description=创建一个新的世界并且加载。
 mv-core.create.name.description=新世界的名称。
-mv-core.create.environment.description=世界的环境。详见：/mv environments
+mv-core.create.environment.description=世界的环境。详见： /mv environments
 mv-core.create.flags.description=附加的世界设置。在 https://gg.gg/nn8bl 上查看所有可能的标志。
 mv-core.create.properties=使用以下属性创建世界 {worldName} ：
-mv-core.create.properties.environment=- 环境: &f{environment}
-mv-core.create.properties.seed=- 种子: &f{seed}
-mv-core.create.properties.worldtype=- 世界类型: &f{worldType}
-mv-core.create.properties.adjustspawn=- 调节出生点: &f{adjustSpawn}
-mv-core.create.properties.biome=- 生物群系: &f{biome}
-mv-core.create.properties.generator=- 生成器: &f{generator}
-mv-core.create.properties.generatorsettings=- 生成器设置: &f{generatorSettings}
+mv-core.create.properties.environment=- 环境： &f{environment}
+mv-core.create.properties.seed=- 种子： &f{seed}
+mv-core.create.properties.worldtype=- 世界类型： &f{worldType}
+mv-core.create.properties.adjustspawn=- 调节出生点： &f{adjustSpawn}
+mv-core.create.properties.biome=- 生物群系： &f{biome}
+mv-core.create.properties.generator=- 生成器： &f{generator}
+mv-core.create.properties.generatorsettings=- 生成器设置： &f{generatorSettings}
 
-mv-core.create.properties.structures=- 结构: &f{structures}
+mv-core.create.properties.structures=- 结构： &f{structures}
 mv-core.create.loading=创建世界中……
 mv-core.create.success=&a世界 '{world}' 已经创建！
 
@@ -65,14 +65,14 @@ mv-core.debug.change.syntax=等级
 mv-core.debug.change.level.description=需要设置的调试等级。
 
 # /mv delete
-mv-core.delete.description=在服务器上永久删除某个世界。
+mv-core.delete.description=在服务器上“永久”删除某个世界。
 mv-core.delete.deleting=正在删除世界 '{world}'……
 mv-core.delete.prompt=你确定想要删除世界 '{world}' 吗？
 mv-core.delete.success=&a世界 '{world}' 已经删除！
 
 # /mv dumps
 mv-core.dumps.description=导出版本信息到控制台或者粘贴服务。
-mv-core.dumps.url.list={service}：{link}
+mv-core.dumps.url.list={service}:{link}
 
 # /mv gamerule set
 mv-core.gamerule.set.description=修改某个世界或某些世界的游戏规则。
@@ -105,24 +105,24 @@ mv-core.generators.empty=&c未找到生成器插件。
 # /mv import
 mv-core.import.description=导入一个已经存在的世界文件夹。
 mv-core.import.name.description=世界文件夹的名称。
-mv-core.import.env.description=世界的环境。详见：/mv env
-mv-core.import.other.description=其他世界设置。详见：https://gg.gg/nn8c2
+mv-core.import.env.description=世界的环境。详见： /mv env
+mv-core.import.other.description=其他世界设置。详见： https://gg.gg/nn8c2
 mv-core.import.importing=开始导入世界 '{world}'……
 mv-core.import.success=&a已导入世界 '{world}'！
 
 # /mv info
 mv-core.info.description=显示某个世界所有已配置的属性。
 mv-core.info.description.world=需要显示信息的世界。
-mv-core.info.header=&a&l---- 世界信息: &f&l{world}&a&l ----
+mv-core.info.header=&a&l---- 世界信息： &f&l{world}&a&l ----
 mv-core.info.nocontent=&c没有找到这样的世界属性！
 
 # /mv list
-mv-core.list.description=显示所有可进入世界的列表。
+mv-core.list.description=显示你所有可进入世界的列表。
 mv-core.list.header=&6====[ 多世界列表 ]====
 mv-core.list.nocontent=&c未找到任何世界，或者你没有权限进入它们！
 
 # /mv load
-mv-core.load.description=加载某个世界，世界必须已经在 worlds.yml，或者请使用 /mv import 导入。
+mv-core.load.description=加载某个世界。世界必须已经在 worlds.yml 中，或者请使用 /mv import 导入。
 mv-core.load.world.description=想要加载的世界名称。
 mv-core.load.loading=加载世界 '{world}' 中……
 mv-core.load.success=&a已加载世界 '{world}'！
@@ -132,6 +132,7 @@ mv-core.modify.description=修改某个给定世界的属性。
 mv-core.modify.world.description=需要修改的世界的名称。
 mv-core.modify.property.description=需要修改的属性。
 mv-core.modify.value.description=需要修改属性的值。
+mv-core.modify.propertyremoved=&c你不能修改 '&3{property}&c'，因为它已经改变或被移除。请使用 '&a{replacement}&c'。
 mv-core.modify.cannothavevalue=你不能指定一个值来 {action} '{property}'。
 mv-core.modify.specifyvalue=你必须指定一个值来 {action} '{property}'。
 mv-core.modify.success=&a成功在世界 &9{world}&a 中 {action} '&9{property}&a' 为 '&9{value}&a' 。
@@ -139,12 +140,12 @@ mv-core.modify.failure=&c在世界 &9{world}&c 中 {action} '&9{property}&c' 为
 mv-core.modify.failure.novalue=&c在世界 &9{world}&c 中 {action} '&9{property}&c' 失败。\n&c{error}
 
 # /mv regen
-mv-core.regen.description=在你的服务器上重新生成一个世界。之前的状态将会被永久丢弃。
+mv-core.regen.description=在你的服务器上重新生成一个世界。之前的状态将会“永久”丢失。
 mv-core.regen.world.description=你想要重新生成的世界。
-mv-core.regen.other.description=其他的世界设置。详见：http://gg.gg/nn8lk
+mv-core.regen.other.description=其他的世界设置。详见： http://gg.gg/nn8lk
 mv-core.regen.regenerating=重新生成世界 '{world}'……
 mv-core.regen.prompt=你确定想要重新生成世界 '{world}' 吗？
-mv-core.regen.success=&a已重新生成 世界 '{world}'！
+mv-core.regen.success=&a已重新生成世界 '{world}'！
 
 # /mv reload
 mv-core.reload.description=重新加载所有 Multiverse 模块的配置文件。
@@ -153,7 +154,7 @@ mv-core.reload.success=&a重新加载完成！
 
 # /mv remove
 mv-core.remove.description=从 Multiverse 中卸载某个世界并从 worlds.yml 中移除。这不会删除世界的文件夹。
-mv-core.remove.world.description=你想要从MV认知中移除的世界。
+mv-core.remove.world.description=你想要从 Multiverse 认知中移除的世界。
 mv-core.remove.success=&a已移除世界 '{world}'！
 
 # /mv
@@ -164,10 +165,10 @@ mv-core.root.help=&a查看 &f/mv help&a 了解可以执行的指令。
 mv-core.setspawn.description=为某个特定的世界设置出生点。
 mv-core.setspawn.location.description=新出生点的位置。
 mv-core.setspawn.world.description=需要设置出生点的目标世界（默认为玩家的当前世界）
-mv-core.setspawn.unsafe=&c新的生成位置不安全！如果这是有意为之，你可以通过使用&6--unsafe&c标志来禁用安全检查。
-mv-core.setspawn.success=&a成功在&6{world}&a中将生成点设置为&6{location}&a！
-mv-core.setspawn.failed=&c在&6{world}&c中将生成点设置为&6{location}&c时失败。{error}
-mv-core.setspawn.notmvworld=&c无法为&c{world}设置生成点，因为它不是一个Multiverse世界。
+mv-core.setspawn.unsafe=&c新出生点不安全！如果是有意为之，你可以通过使用 &6--unsafe&c 标志来禁用安全检查。
+mv-core.setspawn.success=&a成功在 &6{world}&a 中将出生点设置为 &6{location}&a！
+mv-core.setspawn.failed=&c在 &6{world}&c 中将出生点设置为 &6{location}&c 时失败。{error}
+mv-core.setspawn.notmvworld=&c无法为 &c{world} 设置出生点，因为它不是一个 Multiverse 世界。
 
 # /mv spawn
 mv-core.spawn.description=传送某个特定的玩家到他们所在世界的出生点。
@@ -184,7 +185,7 @@ mv-core.teleport.success=已传送 {player} 到 {destination}。
 mv-core.teleport.failed=传送 {player} 到 {destination}失败。{reason}
 
 # /mv unload
-mv-core.unload.description=从 Multiverse 中卸载某个世界。这不会移除世界的文件夹。这不会将它从配置文件中移除。
+mv-core.unload.description=从 Multiverse 中卸载某个世界。这“不会”移除世界的文件夹。这“不会”将它从配置文件中移除。
 mv-core.unload.world.description=你想要卸载的世界名称。
 mv-core.unload.unloading=正在卸载世界 '{world}'……
 mv-core.unload.success=&a已卸载 '{world}'！
@@ -196,7 +197,7 @@ mv-core.usage.description=显示 Multiverse-Core 指令的用法。
 mv-core.version.description=显示版本和作者。
 mv-core.version.mv=Multiverse Core 版本 &fv{version}
 mv-core.version.authors=Multiverse Core 作者 &f{authors}
-mv-core.version.secretcode=特征码: &fFRN002
+mv-core.version.secretcode=特征码： &fFRN002
 
 # /mv who
 # /mv whoall
@@ -205,7 +206,7 @@ mv-core.who.all.description=列出所有世界的玩家
 mv-core.who.world.description=需要列出玩家的世界名称
 mv-core.who.flags.description=筛选 - 仅显示匹配的条目。页码 - 查看的页面序号。
 mv-core.who.empty=&7&o空
-mv-core.who.header=&b====[ 多世界玩家列表 ]====
+mv-core.who.header=&b====[ Multiverse世界玩家列表 ]====
 
 # /mv worldborder
 mv-core.worldborder.center.nothingchanged=&c无变化。世界边界的中心在世界 '&6{world}&c' 中已经有相同的设置。
@@ -214,8 +215,8 @@ mv-core.worldborder.center.success=&r已设置世界 '&6{world}&r' 边界的中
 mv-core.worldborder.damageamount.nothingchanged=&c无变化。世界边界的伤害在世界 '&6{world}&c' 中已经有相同的设置。
 mv-core.worldborder.damageamount.success=&r已设置世界 '&6{world}&r' 的边界伤害为每秒每格 {amount} 点伤害。
 
-mv-core.worldborder.damagebuffer.nothingchanged=&c无变化。世界边界伤害的缓冲在世界 '&6{world}&c' 中已经有相同的设置。
-mv-core.worldborder.damagebuffer.success=&r已设置世界 '&6{world}&r' 边界伤害的缓冲为 {distance} 格。
+mv-core.worldborder.damagebuffer.nothingchanged=&c无变化。世界边界伤害的缓冲区在世界 '&6{world}&c' 中已经有相同的设置。
+mv-core.worldborder.damagebuffer.success=&r已设置世界 '&6{world}&r' 边界伤害的缓冲区为 {distance} 格。
 
 mv-core.worldborder.get.size=&r世界 '&6{world}&r' 的边界宽度目前为 {size} 格。
 
@@ -232,7 +233,7 @@ mv-core.worldborder.warningtime.success=&r已设置世界 '&6{world}&r' 的边
 
 # commands error
 mv-core.commands.error.playersonly=&c该指令仅玩家可以使用。
-mv-core.commands.error.multiverseworldonly=&c该指令仅可以在多世界中使用。
+mv-core.commands.error.multiverseworldonly=&c该指令仅可以在Multiverse世界中使用。
 
 # entry check
 mv-core.entrycheck.blacklisted='{world}' 在黑名单中。
@@ -242,29 +243,29 @@ mv-core.entrycheck.exceedplayerlimit=该世界已经达到最大玩家数量限
 mv-core.entrycheck.noworldaccess=你没有权限进入该世界。
 
 # economy
-mv-core.economy.item.deposit=&a{price}&f已存入你的背包。
-mv-core.economy.item.withdraw=&f你已被收取&a{price}。
-mv-core.economy.vault.deposit=&2{price}&f已存入你的账户。
-mv-core.economy.vault.withdraw=&f你已被收取&2{price}。
+mv-core.economy.item.deposit=&a{price}&f 已存入你的背包。
+mv-core.economy.item.withdraw=&f你已被收取 &a{price}。
+mv-core.economy.vault.deposit=&2{price}&f 已存入你的账户。
+mv-core.economy.vault.withdraw=&f你已被收取 &2{price}。
 
 # multiverse parse destination failure reason
 mv-core.destination.anchor.failurereason.anchornotfound=&c锚点 '&6{anchor}&c' 不存在！
 mv-core.destination.bed.failurereason.playernotfound=&玩家 '&6{player}&c' 不存在或不在线！如果想传送到自己的床，使用 'playerbed'。
-mv-core.destination.cannon.failurereason.invalidformat=&c大炮目标格式是：&6ca:worldname:x,y,z:pitch:yaw:speed
-mv-core.destination.exact.failurereason.invalidformat=&c精确目标格式是：&6e:worldname:x,y,z:pitch:yaw
+mv-core.destination.cannon.failurereason.invalidformat=&c大炮目标格式是： &6ca:worldname:x,y,z:pitch:yaw:speed
+mv-core.destination.exact.failurereason.invalidformat=&c精确目标格式是： &6e:worldname:x,y,z:pitch:yaw
 mv-core.destination.player.failurereason.playernotfound=&c玩家 '&6{player}&c' 不存在或不在线！
-mv-core.destination.shared.failurereason.invalidcoordinatesformat=你必须指定一个具有以下格式有效的坐标：&6{x},{y},{z}
-mv-core.destination.shared.failurereason.invalidnumberformat=给定的值不是一个有效的数字。{error}。
+mv-core.destination.shared.failurereason.invalidcoordinatesformat=你必须指定一个具有以下格式有效的坐标： &6{x},{y},{z}
+mv-core.destination.shared.failurereason.invalidnumberformat=无效的目标输入。{error}。
 mv-core.destination.shared.failurereason.worldnotfound=&c世界 '&6{world}&c' 不存在或着未被加载！
-mv-core.destination.parse.failurereason.invaliddestinationid=无效的目标ID：{id}。有效的目标ID有：{ids}
+mv-core.destination.parse.failurereason.invaliddestinationid=无效的目标ID： {id}。有效的目标ID有： {ids}
 
 # teleport failure reason
 mv-core.teleportfailurereason.null.destination=目标无效！
 mv-core.teleportfailurereason.null.location=位置无效！
-mv-core.teleportfailurereason.null.world=&c位置所在的世界无效！
-mv-core.teleportfailurereason.unsafe.location=位置是不安全的！使用 `--unsafe` 忽视该问题。
-mv-core.teleportfailurereason.teleport.failed=出于某些拒绝了该传送。
-mv-core.teleportfailurereason.teleport.failed.exception=在传送过程中出现了一个错误。查看控制台获取更多信息。
+mv-core.teleportfailurereason.null.world=&c目标世界没有加载或者不存在！
+mv-core.teleportfailurereason.unsafe.location=位置被认为是不安全的！如果是有意为之，使用 `--unsafe` 强制执行。
+mv-core.teleportfailurereason.teleport.failed=传送被拒绝。请确保其他插件没有阻止传送，并查看服务器的日志获得错误信息。
+mv-core.teleportfailurereason.teleport.failed.exception=在传送过程中出现了一个错误。查看服务器日志获取更多信息。
 mv-core.teleportfailurereason.event.cancelled=传送被另一个插件取消了。
 
 # world manager result
@@ -272,7 +273,8 @@ mv-core.cloneworld.invalidworldname=世界 '{world}' 包含无效的字符！
 mv-core.cloneworld.worldexistfolder=世界 '{world}' 已经存在于服务器的文件中！在复制前你需要先删除它。
 mv-core.cloneworld.worldexistunloaded=世界 '{world}' 已经存在并且未被加载！在复制前你需要先删除它。
 mv-core.cloneworld.worldexistloaded=世界 '{world}' 已经存在！在复制前你需要先删除它。
-mv-core.cloneworld.copyfailed=复制世界到 '{world}' 失败：{error}\n&f查看控制台获取更多信息。
+mv-core.cloneworld.fromworldfolderinvalid=源世界 '{world}' 文件夹的内容似乎不是一个有效的世界！请确保它包含正确的世界数据和区域文件夹结构。
+mv-core.cloneworld.copyfailed=复制世界到 '{world}' 失败： {error}\n&f查看控制台获取更多信息。
 
 mv-core.createworld.invalidworldname=世界 '{world}' 包含无效的字符！
 mv-core.createworld.worldexistfolder=世界 '{world}' 已经存在于服务器的文件中！&f  如果你想要导入它，输入 '&a/mv import {world} <environment>&f'。
@@ -280,35 +282,37 @@ mv-core.createworld.worldexistunloaded=世界 '{world}' 已经存在, 但是未
 mv-core.createworld.worldexistloaded=世界 '{world}' 已经存在！
 
 mv-core.deleteworld.worldnonexistent=世界 '{world}' 不存在！
-mv-core.deleteworld.loadfailed=不能加载世界 '{world}'，请确认世界文件夹是否存在。&f 你可以执行 '&a/mv remove {world}&f' 将它从 Multiverse 中移除，或者使用 '&a/mv load {world}&f' 尝试重新加载。
-mv-core.deleteworld.worldfoldernotfound=世界 '{world}' folder not found！
-mv-core.deleteworld.failedtodeletefolder=删除世界 '{world}' 的文件夹失败：{error}\n&f查看控制台获取更多信息。
+mv-core.deleteworld.loadfailed=不能加载世界 '{world}'，请确认世界文件夹是否被删除或者损坏。&f 你可以执行 '&a/mv remove {world}&f' 将它从 Multiverse 中移除，或者使用 '&a/mv load {world}&f' 尝试重新加载。
+mv-core.deleteworld.worldfoldernotfound=&c无法定位 '{world}' 文件夹！&f 你可以执行 '&a/mv remove {world}&c' 将它从 Multiverse 中移除，如果存在，也可以手动删除文件夹。
+mv-core.deleteworld.failedtodeletefolder=删除世界 '{world}' 的文件夹失败： {error}\n&f查看控制台获取更多信息。
 
 mv-core.importworld.invalidworldname=世界 '{world}' 包含无效的字符！
 mv-core.importworld.worldexistunloaded=世界 '{world}' 已经存在, 但是未被加载！&f 如果你想要加载它，输入 '&a/mv load {world}&f'。
 mv-core.importworld.worldexistloaded=世界 '{world}' 已经存在！
-mv-core.importworld.worldfolderinvalid=世界 '{world}' 文件夹的内容看上去不像是一个有效的世界！
+mv-core.importworld.worldfolderinvalid=世界 '{world}' 文件夹的内容似乎不是一个有效的世界！请确保它包含正确的世界数据和区域文件夹结构。\n&c如果服务器软件对世界文件夹的处理方式不同，或者你确信世界是有效的，使用 '&3--skip-folder-check&c' 标志。
+mv-core.importworld.bukkitenvironmentmismatch=环境不匹配！&f 世界 '{world}' 已经用环境 '{bukkitEnvironment}' 加载，但 Multiverse 正在尝试用环境 '{mvEnvironment}' 导入它。
 
 mv-core.loadworld.worldalreadyloading=世界 '{world}' 已经正在加载！请稍后……
 mv-core.loadworld.worldnonexistent=世界 '{world}' 不存在！使用 '&a/mv create {world} <environment>&f' 来创建。
 mv-core.loadworld.worldexistfolder=世界 '{world}' 已经存在于服务器的文件中, 但是未被 Multiverse 识别！&f 如果你想要导入它，输入 '&a/mv import {world} <environment>&f'。
-mv-core.loadworld.worldexistloaded=世界 '{world}' 已经存在！
+mv-core.loadworld.worldexistloaded=世界 '{world}' 已经加载！
+mv-core.loadworld.bukkitenvironmentmismatch=环境不匹配！&f 世界 '{world}' 已经用环境 '{bukkitEnvironment}' 加载，但 Multiverse 正在尝试用环境 '{mvEnvironment}' 加载它。
 
 mv-core.removeworld.worldnonexistent=世界 '{world}' 不存在！
 
 mv-core.unloadworld.worldalreadyunloading=世界 '{world}' 已经在卸载！ 请稍后……
 mv-core.unloadworld.worldnonexistent=世界 '{world}' 不存在！
 mv-core.unloadworld.worldunloaded=世界 '{world}' 已经卸载！
-mv-core.unloadworld.bukkitunloadfailed=Bukkit 卸载世界 '{world}' 失败：{error}
+mv-core.unloadworld.bukkitunloadfailed=Bukkit 卸载世界 '{world}' 失败： {error}
 
 mv-core.worldcreator.invalidbiomeprovider=&c无效的生物群系 '&6{biome}&c'！{error}\n&c查看控制台获取更多信息。
 mv-core.worldcreator.invalidchunkgenerator=&c无效的区块生成器 '&6{generator}&c'！ {error}\n&c这更像是生成器插件的问题，而不是 Multiverse。查看控制台获取更多信息。
-mv-core.worldcreator.bukkitcreationfailed=&cBukkit 创建世界 '{world}' 失败：{error}\n&c查看控制台获取更多信息。
+mv-core.worldcreator.bukkitcreationfailed=&cBukkit 创建世界 '{world}' 失败： {error}\n&c查看控制台获取更多信息。
 
 # queue command result
 mv-core.queuecommand.nocommandinqueue=&c你没有任何指令在列队中。
 mv-core.queuecommand.invalidotp=&c无效的 OTP 数字 '&6{otp}&c'。请重试……
-mv-core.queuecommand.commandexecutionerror=&c在处理列队中命令时发生了错误：{error}\n&f查看控制台获取更多信息。
+mv-core.queuecommand.commandexecutionerror=&c在处理列队中命令时发生了错误： {error}\n&f查看控制台获取更多信息。
 
 # content display messages
 mv-core.contentdisplay.nocontent=&c没有可显示的内容
@@ -322,7 +326,12 @@ mv-core.contentdisplay.null=&7&o错误
 mv-core.exception.multiverseworld.createnull=创建的世界返回为null！
 mv-core.exception.multiverseworld.unloaddefaultworld=&c你不能卸载默认的世界！世界 &6{world}&c 是定义在 server.properties '&6level-name&c' 中的默认世界。
 mv-core.exception.multiverseworld.unloadplayersinworld=&c目前仍然有 &6{count}&c 位玩家在世界中！在命令中使用 '&6--remove-players&c' 标签将所有的玩家从世界中移除。
-mv-core.exception.multiverseworld.unloaderror=&c在卸载世界 &6{world}&c 过程中出现了一个位置的错误。\n&c查看控制台获取更多信息。
+mv-core.exception.multiverseworld.unloaderror=&c在卸载世界 &6{world}&c 过程中出现了一个未知的错误。\n&c查看控制台获取更多信息。
+
+# multiverse position parse exception
+mv-core.exception.positionparse.invaliddirection=&c无效的方向字符串格式： {format}。预期的格式： <pitch>:<yaw>
+mv-core.exception.positionparse.invalidcoordinates=&c无效的坐标格式： {format}。预期的格式： <x>,<y>,<z>
+mv-core.exception.positionparse.invalidnumber=&c无效的数字格式： {number}。预期为一个数字值。
 
 # generic
 mv-core.generic.success=成功！

src/main/resources/plugin.yml

@@ -1,7 +1,8 @@
 name: Multiverse-Core
 main: org.mvplugins.multiverse.core.MultiverseCore
 authors: ['dumptruckman', 'Rigby', 'fernferret', 'lithium3141', 'main--', 'benwoo1110', 'Zax71']
-website: 'https://dev.bukkit.org/projects/multiverse-core'
+website: 'https://modrinth.com/plugin/multiverse-core'
+description: 'The original Bukkit Multi-World Plugin!'
 softdepend: ['Vault', 'PlaceholderAPI']
 api-version: 1.13
 version: ${version}

src/test/java/org/mvplugins/multiverse/core/config/node/MapConfigNodeTest.kt

@@ -0,0 +1,54 @@
+package org.mvplugins.multiverse.core.config.node
+
+import io.vavr.control.Try
+import kotlin.test.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertTrue
+
+class MapConfigNodeTest {
+
+    @Test
+    fun `MapConfigNode parses from string with defaults`() {
+        val node: MapConfigNode<String, Int> =
+            MapConfigNode.mapBuilder("my-map", String::class.java, Int::class.javaObjectType).build()
+        val expected: Map<String, Int> = mapOf("key1" to 1, "key2" to 2)
+
+        assertEquals(
+            expected,
+            node.parseFromString("key1=1;key2=2").get()
+        )
+        assertEquals(emptyMap(), node.parseFromString("  ").get())
+    }
+
+    @Test
+    fun `MapConfigNode default serializer converts values by key and value type`() {
+        val node: MapConfigNode<String, Int> =
+            MapConfigNode.mapBuilder("my-map", String::class.java, Int::class.javaObjectType).build()
+        val serializer = node.serializer
+        val expected: Map<String, Int> = mapOf("alpha" to 4, "beta" to 8)
+        val rawMap: Map<String, Any> = mapOf("alpha" to "4", "beta" to 8)
+
+        val deserialized = serializer!!.deserialize(rawMap, node.type)
+        assertEquals(expected, deserialized)
+
+        val serialized = serializer.serialize(expected, node.type)
+        assertEquals(expected, serialized)
+    }
+
+    @Test
+    fun `MapConfigNode key and value validators are used for node validation`() {
+        val node: MapConfigNode<String, Int> =
+            MapConfigNode.mapBuilder("my-map", String::class.java, Int::class.javaObjectType)
+            .keyValidator { key ->
+                if (key.startsWith("k")) Try.success(null) else Try.failure(IllegalArgumentException("invalid key"))
+            }
+            .valueValidator { value ->
+                if (value >= 0) Try.success(null) else Try.failure(IllegalArgumentException("invalid value"))
+            }
+            .build()
+
+        assertTrue(node.validate(mapOf("key" to 1)).isSuccess)
+        assertTrue(node.validate(mapOf("bad" to 1)).isFailure)
+        assertTrue(node.validate(mapOf("key" to -1)).isFailure)
+    }
+}

src/test/java/org/mvplugins/multiverse/core/inject/InjectionTest.kt

@@ -77,7 +77,7 @@ class InjectionTest : TestWithMockBukkit() {
     @Test
     fun `Commands are available as services`() {
         val commands = serviceLocator.getAllActiveServices(CoreCommand::class.java)
-        assertEquals(57, commands.size)
+        assertEquals(58, commands.size)
     }
 
     @Test

src/test/java/org/mvplugins/multiverse/core/mock/MVServerMock.java

@@ -39,6 +39,8 @@ public class MVServerMock extends ServerMock {
         world.getWorldFolder().mkdirs();
         createFile(new File(world.getWorldFolder(), "uid.dat"));
         createFile(new File(world.getWorldFolder(), "level.dat"));
+        new File(world.getWorldFolder(), "region").mkdir();
+        new File(world.getWorldFolder(), "data").mkdir();
         addWorld(world);
         return world;
     }

src/test/java/org/mvplugins/multiverse/core/utils/StringFormatterTest.kt

@@ -2,6 +2,7 @@ package org.mvplugins.multiverse.core.utils
 
 import kotlin.test.Test
 import kotlin.test.assertEquals
+import kotlin.test.assertNull
 
 class StringFormatterTest {
     @Test
@@ -42,5 +43,22 @@ class StringFormatterTest {
             "test",
             StringFormatter.quoteMultiWordString("test")
         )
+        assertNull(StringFormatter.quoteMultiWordString(null))
+    }
+
+    @Test
+    fun `StringFormatter parseCSVMap`() {
+        assertEquals(
+            emptyMap<String, String>(),
+            StringFormatter.parseCSVMap("")
+        )
+        assertEquals(
+            mapOf("key" to "value"),
+            StringFormatter.parseCSVMap("key=value")
+        )
+        assertEquals(
+            mapOf("key1" to "value1", "key2" to "value2", "key3" to "value3"),
+            StringFormatter.parseCSVMap("key1=value1,key2=value2,key3=value3")
+        )
     }
 }