Clock API and level clock overrides

paper-api/src/generated/java/io/papermc/paper/registry/keys/TimelineKeys.java

@@ -0,0 +1,68 @@
+package io.papermc.paper.registry.keys;
+
+import static net.kyori.adventure.key.Key.key;
+
+import io.papermc.paper.annotation.GeneratedClass;
+import io.papermc.paper.registry.RegistryKey;
+import io.papermc.paper.registry.TypedKey;
+import io.papermc.paper.world.Timeline;
+import net.kyori.adventure.key.Key;
+import org.jspecify.annotations.NullMarked;
+
+/**
+ * Vanilla keys for {@link RegistryKey#TIMELINE}.
+ *
+ * @apiNote The fields provided here are a direct representation of
+ * what is available from the vanilla game source. They may be
+ * changed (including removals) on any Minecraft version
+ * bump, so cross-version compatibility is not provided on the
+ * same level as it is on most of the other API.
+ */
+@SuppressWarnings({
+        "unused",
+        "SpellCheckingInspection"
+})
+@NullMarked
+@GeneratedClass
+public final class TimelineKeys {
+    /**
+     * {@code minecraft:day}
+     *
+     * @apiNote This field is version-dependant and may be removed in future Minecraft versions
+     */
+    public static final TypedKey<Timeline> DAY = create(key("day"));
+
+    /**
+     * {@code minecraft:early_game}
+     *
+     * @apiNote This field is version-dependant and may be removed in future Minecraft versions
+     */
+    public static final TypedKey<Timeline> EARLY_GAME = create(key("early_game"));
+
+    /**
+     * {@code minecraft:moon}
+     *
+     * @apiNote This field is version-dependant and may be removed in future Minecraft versions
+     */
+    public static final TypedKey<Timeline> MOON = create(key("moon"));
+
+    /**
+     * {@code minecraft:villager_schedule}
+     *
+     * @apiNote This field is version-dependant and may be removed in future Minecraft versions
+     */
+    public static final TypedKey<Timeline> VILLAGER_SCHEDULE = create(key("villager_schedule"));
+
+    private TimelineKeys() {
+    }
+
+    /**
+     * Creates a typed key for {@link Timeline} in the registry {@code minecraft:timeline}.
+     *
+     * @param key the value's key in the registry
+     * @return a new typed key
+     */
+    public static TypedKey<Timeline> create(final Key key) {
+        return TypedKey.create(RegistryKey.TIMELINE, key);
+    }
+}

paper-api/src/generated/java/io/papermc/paper/registry/keys/WorldClockKeys.java

@@ -0,0 +1,54 @@
+package io.papermc.paper.registry.keys;
+
+import static net.kyori.adventure.key.Key.key;
+
+import io.papermc.paper.annotation.GeneratedClass;
+import io.papermc.paper.registry.RegistryKey;
+import io.papermc.paper.registry.TypedKey;
+import io.papermc.paper.world.WorldClock;
+import net.kyori.adventure.key.Key;
+import org.jspecify.annotations.NullMarked;
+
+/**
+ * Vanilla keys for {@link RegistryKey#WORLD_CLOCK}.
+ *
+ * @apiNote The fields provided here are a direct representation of
+ * what is available from the vanilla game source. They may be
+ * changed (including removals) on any Minecraft version
+ * bump, so cross-version compatibility is not provided on the
+ * same level as it is on most of the other API.
+ */
+@SuppressWarnings({
+        "unused",
+        "SpellCheckingInspection"
+})
+@NullMarked
+@GeneratedClass
+public final class WorldClockKeys {
+    /**
+     * {@code minecraft:overworld}
+     *
+     * @apiNote This field is version-dependant and may be removed in future Minecraft versions
+     */
+    public static final TypedKey<WorldClock> OVERWORLD = create(key("overworld"));
+
+    /**
+     * {@code minecraft:the_end}
+     *
+     * @apiNote This field is version-dependant and may be removed in future Minecraft versions
+     */
+    public static final TypedKey<WorldClock> THE_END = create(key("the_end"));
+
+    private WorldClockKeys() {
+    }
+
+    /**
+     * Creates a typed key for {@link WorldClock} in the registry {@code minecraft:world_clock}.
+     *
+     * @param key the value's key in the registry
+     * @return a new typed key
+     */
+    public static TypedKey<WorldClock> create(final Key key) {
+        return TypedKey.create(RegistryKey.WORLD_CLOCK, key);
+    }
+}

paper-api/src/generated/java/io/papermc/paper/registry/keys/tags/TimelineTagKeys.java

@@ -0,0 +1,68 @@
+package io.papermc.paper.registry.keys.tags;
+
+import static net.kyori.adventure.key.Key.key;
+
+import io.papermc.paper.annotation.GeneratedClass;
+import io.papermc.paper.registry.RegistryKey;
+import io.papermc.paper.registry.tag.TagKey;
+import io.papermc.paper.world.Timeline;
+import net.kyori.adventure.key.Key;
+import org.jspecify.annotations.NullMarked;
+
+/**
+ * Vanilla tag keys for {@link RegistryKey#TIMELINE}.
+ *
+ * @apiNote The fields provided here are a direct representation of
+ * what is available from the vanilla game source. They may be
+ * changed (including removals) on any Minecraft version
+ * bump, so cross-version compatibility is not provided on the
+ * same level as it is on most of the other API.
+ */
+@SuppressWarnings({
+        "unused",
+        "SpellCheckingInspection"
+})
+@NullMarked
+@GeneratedClass
+public final class TimelineTagKeys {
+    /**
+     * {@code #minecraft:in_end}
+     *
+     * @apiNote This field is version-dependant and may be removed in future Minecraft versions
+     */
+    public static final TagKey<Timeline> IN_END = create(key("in_end"));
+
+    /**
+     * {@code #minecraft:in_nether}
+     *
+     * @apiNote This field is version-dependant and may be removed in future Minecraft versions
+     */
+    public static final TagKey<Timeline> IN_NETHER = create(key("in_nether"));
+
+    /**
+     * {@code #minecraft:in_overworld}
+     *
+     * @apiNote This field is version-dependant and may be removed in future Minecraft versions
+     */
+    public static final TagKey<Timeline> IN_OVERWORLD = create(key("in_overworld"));
+
+    /**
+     * {@code #minecraft:universal}
+     *
+     * @apiNote This field is version-dependant and may be removed in future Minecraft versions
+     */
+    public static final TagKey<Timeline> UNIVERSAL = create(key("universal"));
+
+    private TimelineTagKeys() {
+    }
+
+    /**
+     * Creates a tag key for {@link Timeline} in the registry {@code minecraft:timeline}.
+     *
+     * @param key the tag key's key
+     * @return a new tag key
+     */
+    public static TagKey<Timeline> create(final Key key) {
+        return TagKey.create(RegistryKey.TIMELINE, key);
+    }
+}

paper-api/src/main/java/io/papermc/paper/registry/RegistryKey.java

@@ -3,6 +3,8 @@ package io.papermc.paper.registry;
 import io.papermc.paper.datacomponent.DataComponentType;
 import io.papermc.paper.dialog.Dialog;
 import io.papermc.paper.registry.tag.TagKey;
+import io.papermc.paper.world.Timeline;
+import io.papermc.paper.world.WorldClock;
 import net.kyori.adventure.key.Key;
 import net.kyori.adventure.key.KeyPattern;
 import net.kyori.adventure.key.Keyed;
@@ -251,6 +253,16 @@ public sealed interface RegistryKey<T> extends Keyed permits RegistryKeyImpl {
      * @see io.papermc.paper.registry.keys.DialogKeys
      */
     RegistryKey<Dialog> DIALOG = create("dialog");
+    /**
+     * Data-driven registry for world clocks.
+     * @see io.papermc.paper.registry.keys.WorldClockKeys
+     */
+    RegistryKey<WorldClock> WORLD_CLOCK = create("world_clock");
+    /**
+     * Data-driven registry for timelines.
+     * @see io.papermc.paper.registry.keys.TimelineKeys
+     */
+    RegistryKey<Timeline> TIMELINE = create("timeline");
 
 
     /* ******************* *

paper-api/src/main/java/io/papermc/paper/registry/data/TimelineRegistryEntry.java

@@ -0,0 +1,103 @@
+package io.papermc.paper.registry.data;
+
+import io.papermc.paper.registry.RegistryBuilder;
+import io.papermc.paper.registry.TypedKey;
+import io.papermc.paper.world.Timeline;
+import io.papermc.paper.world.WorldClock;
+import java.util.Map;
+import java.util.OptionalInt;
+import net.kyori.adventure.key.Key;
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.Contract;
+import org.jetbrains.annotations.Range;
+
+/**
+ * A data-centric version-specific registry entry for the {@link Timeline} type.
+ */
+@ApiStatus.Experimental
+@ApiStatus.NonExtendable
+public interface TimelineRegistryEntry {
+
+    /**
+     * Gets the clock that drives this timeline.
+     *
+     * @return the clock
+     */
+    @Contract(pure = true)
+    TypedKey<WorldClock> clock();
+
+    /**
+     * Gets the timeline period, if any.
+     *
+     * @return the timeline period
+     */
+    @Contract(pure = true)
+    OptionalInt periodTicks();
+
+    /**
+     * Gets the time markers defined by this timeline.
+     *
+     * @return the time markers
+     */
+    @Contract(pure = true)
+    Map<Key, TimeMarker> timeMarkers();
+
+    /**
+     * A mutable builder for the {@link TimelineRegistryEntry} plugins may change in applicable registry events.
+     * <p>
+     * The following values are required for each builder:
+     * <ul>
+     *     <li>{@link #clock(TypedKey)}</li>
+     * </ul>
+     */
+    @ApiStatus.Experimental
+    @ApiStatus.NonExtendable
+    interface Builder extends TimelineRegistryEntry, RegistryBuilder<Timeline> {
+
+        /**
+         * Sets the clock that drives this timeline.
+         *
+         * @param clock the clock
+         * @return this builder
+         */
+        @Contract(value = "_ -> this", mutates = "this")
+        Builder clock(TypedKey<WorldClock> clock);
+
+        /**
+         * Sets the timeline period.
+         *
+         * @param periodTicks the period in ticks
+         * @return this builder
+         */
+        @Contract(value = "_ -> this", mutates = "this")
+        Builder periodTicks(@Range(from = 1, to = Integer.MAX_VALUE) int periodTicks);
+
+        /**
+         * Clears the timeline period.
+         *
+         * @return this builder
+         */
+        @Contract(value = "-> this", mutates = "this")
+        Builder clearPeriodTicks();
+
+        /**
+         * Adds or replaces a time marker on this timeline.
+         *
+         * @param key the time marker key
+         * @param ticks the marker tick
+         * @param showInCommands whether the marker should be suggested in commands
+         * @return this builder
+         */
+        @Contract(value = "_, _, _ -> this", mutates = "this")
+        Builder addTimeMarker(Key key, @Range(from = 0, to = Integer.MAX_VALUE) int ticks, boolean showInCommands);
+    }
+
+    /**
+     * A time marker defined by a timeline.
+     *
+     * @param ticks the tick this marker occurs on
+     * @param showInCommands whether the marker should be suggested in commands
+     */
+    record TimeMarker(@Range(from = 0, to = Integer.MAX_VALUE) int ticks, boolean showInCommands) {
+    }
+}

paper-api/src/main/java/io/papermc/paper/registry/data/WorldClockRegistryEntry.java

@@ -0,0 +1,21 @@
+package io.papermc.paper.registry.data;
+
+import io.papermc.paper.registry.RegistryBuilder;
+import io.papermc.paper.world.WorldClock;
+import org.jetbrains.annotations.ApiStatus;
+
+/**
+ * A data-centric version-specific registry entry for the {@link WorldClock} type.
+ */
+@ApiStatus.Experimental
+@ApiStatus.NonExtendable
+public interface WorldClockRegistryEntry {
+
+    /**
+     * A mutable builder for the {@link WorldClockRegistryEntry} plugins may change in applicable registry events.
+     */
+    @ApiStatus.Experimental
+    @ApiStatus.NonExtendable
+    interface Builder extends WorldClockRegistryEntry, RegistryBuilder<WorldClock> {
+    }
+}

paper-api/src/main/java/io/papermc/paper/registry/event/RegistryEvents.java

@@ -14,9 +14,13 @@ import io.papermc.paper.registry.data.InstrumentRegistryEntry;
 import io.papermc.paper.registry.data.JukeboxSongRegistryEntry;
 import io.papermc.paper.registry.data.PaintingVariantRegistryEntry;
 import io.papermc.paper.registry.data.PigVariantRegistryEntry;
+import io.papermc.paper.registry.data.TimelineRegistryEntry;
 import io.papermc.paper.registry.data.WolfVariantRegistryEntry;
+import io.papermc.paper.registry.data.WorldClockRegistryEntry;
 import io.papermc.paper.registry.data.ZombieNautilusVariantRegistryEntry;
 import io.papermc.paper.registry.data.dialog.DialogRegistryEntry;
+import io.papermc.paper.world.Timeline;
+import io.papermc.paper.world.WorldClock;
 import org.bukkit.Art;
 import org.bukkit.GameEvent;
 import org.bukkit.JukeboxSong;
@@ -56,6 +60,8 @@ public final class RegistryEvents {
     public static final RegistryEventProvider<Pig.Variant, PigVariantRegistryEntry.Builder> PIG_VARIANT = create(RegistryKey.PIG_VARIANT);
     public static final RegistryEventProvider<ZombieNautilus.Variant, ZombieNautilusVariantRegistryEntry.Builder> ZOMBIE_NAUTILUS_VARIANT = create(RegistryKey.ZOMBIE_NAUTILUS_VARIANT);
     public static final RegistryEventProvider<Dialog, DialogRegistryEntry.Builder> DIALOG = create(RegistryKey.DIALOG);
+    public static final RegistryEventProvider<WorldClock, WorldClockRegistryEntry.Builder> WORLD_CLOCK = create(RegistryKey.WORLD_CLOCK);
+    public static final RegistryEventProvider<Timeline, TimelineRegistryEntry.Builder> TIMELINE = create(RegistryKey.TIMELINE);
     // End generate - RegistryEvents
 
     private RegistryEvents() {

paper-api/src/main/java/io/papermc/paper/world/Timeline.java

@@ -0,0 +1,11 @@
+package io.papermc.paper.world;
+
+import org.bukkit.Keyed;
+import org.jetbrains.annotations.ApiStatus;
+
+/**
+ * Represents a timeline that can apply world attributes or define time markers for a {@link WorldClock}.
+ */
+@ApiStatus.Experimental
+public interface Timeline extends Keyed {
+}

paper-api/src/main/java/io/papermc/paper/world/WorldClock.java

@@ -0,0 +1,11 @@
+package io.papermc.paper.world;
+
+import org.bukkit.Keyed;
+import org.jetbrains.annotations.ApiStatus;
+
+/**
+ * Represents a world clock.
+ */
+@ApiStatus.Experimental
+public interface WorldClock extends Keyed {
+}

paper-api/src/main/java/org/bukkit/Server.java

@@ -16,6 +16,7 @@ import java.util.UUID;
 import java.util.function.Consumer;
 import java.util.logging.Logger;
 import io.papermc.paper.configuration.ServerConfiguration;
+import io.papermc.paper.world.WorldClock;
 import net.kyori.adventure.text.Component;
 import net.kyori.adventure.text.minimessage.MiniMessage;
 import net.kyori.adventure.text.minimessage.tag.resolver.TagResolver;
@@ -165,6 +166,85 @@ public interface Server extends PluginMessageRecipient, net.kyori.adventure.audi
     @NotNull
     public Collection<? extends Player> getOnlinePlayers();
 
+    /**
+     * Gets the relative in-game time of the specified clock.
+     * <p>
+     * The relative time is analogous to hours * 1000
+     *
+     * @param clock the clock
+     * @return The current relative time
+     * @see #getFullTime(WorldClock) Returns an absolute time of the clock
+     */
+    public long getTime(@NotNull WorldClock clock);
+
+    /**
+     * Sets the relative in-game time of the specified clock.
+     * <p>
+     * The relative time is analogous to hours * 1000
+     * <p>
+     * Note that setting the relative time below the current relative time
+     * will actually move the clock forward a day. If you require to rewind
+     * time, please see {@link #setFullTime(WorldClock, long)}
+     *
+     * @param clock the clock
+     * @param time The new relative time to set the clock to (in hours*1000)
+     * @see #setFullTime(WorldClock, long) Sets the absolute time of a specific clock
+     */
+    public void setTime(@NotNull WorldClock clock, long time);
+
+    /**
+     * Gets the full in-game time of the specified clock.
+     *
+     * @param clock the clock
+     * @return The current absolute time
+     * @see #getTime(WorldClock) Returns a relative time of the clock
+     */
+    public long getFullTime(@NotNull WorldClock clock);
+
+    /**
+     * Sets the in-game time of the specified clock.
+     * <p>
+     * Note that this sets the full time of the clock, which may cause adverse
+     * effects such as breaking redstone clocks and any scheduled events
+     *
+     * @param clock the clock
+     * @param time The new absolute time to set this clock to
+     * @see #setTime(WorldClock, long) Sets the relative time of a specific clock
+     */
+    public void setFullTime(@NotNull WorldClock clock, long time);
+
+    /**
+     * Gets whether the specified clock is paused.
+     *
+     * @param clock the clock
+     * @return whether the clock is paused
+     */
+    public boolean isClockPaused(@NotNull WorldClock clock);
+
+    /**
+     * Sets whether the specified clock is paused.
+     *
+     * @param clock the clock
+     * @param paused whether the clock is paused
+     */
+    public void setClockPaused(@NotNull WorldClock clock, boolean paused);
+
+    /**
+     * Gets the rate of the specified clock.
+     *
+     * @param clock the clock
+     * @return the clock rate
+     */
+    public float getClockRate(@NotNull WorldClock clock);
+
+    /**
+     * Sets the rate of the specified clock.
+     *
+     * @param clock the clock
+     * @param rate the clock rate
+     */
+    public void setClockRate(@NotNull WorldClock clock, float rate);
+
     /**
      * Get the maximum amount of players which can login to this server.
      *

paper-api/src/main/java/org/bukkit/World.java

@@ -1,6 +1,8 @@
 package org.bukkit;
 
 import io.papermc.paper.raytracing.PositionedRayTraceConfigurationBuilder;
+import io.papermc.paper.world.Timeline;
+import io.papermc.paper.world.WorldClock;
 import java.io.File;
 import java.nio.file.Path;
 import java.util.ArrayList;
@@ -2071,8 +2073,10 @@ public interface World extends RegionAccessor, WorldInfo, PluginMessageRecipient
      *
      * @param time The new relative time to set the in-game time to (in
      *     hours*1000)
-     * @see #setFullTime(long) Sets the absolute time of this world
+     * @see Server#setTime(WorldClock, long) Sets the relative time of a specific clock
+     * @deprecated use {@link Server#setTime(WorldClock, long)} with {@link #getClock()} instead
      */
+    @Deprecated(since = "26.1")
     public void setTime(long time);
 
     /**
@@ -2090,13 +2094,31 @@ public interface World extends RegionAccessor, WorldInfo, PluginMessageRecipient
      * effects such as breaking redstone clocks and any scheduled events
      *
      * @param time The new absolute time to set this world to
-     * @see #setTime(long) Sets the relative time of this world
-     * @deprecated all overworlds share the same world clock by default now
+     * @see Server#setFullTime(WorldClock, long) Sets the absolute time of a specific clock
+     * @deprecated use {@link Server#setFullTime(WorldClock, long)} with {@link #getClock()} instead
      * @throws IllegalArgumentException if this world does not have a world clock (e.g. the nether)
      */
-    @Deprecated // TODO world clock API with links to it
+    @Deprecated(since = "26.1")
     public void setFullTime(long time);
 
+    /**
+     * Gets the clock of this world.
+     * <p>
+     * This may be a world-specific override of the dimension type's clock.
+     *
+     * @return the clock, or null if this world does not have one
+     */
+    @Nullable
+    public WorldClock getClock();
+
+    /**
+     * Gets the timelines applied by this world's dimension type.
+     *
+     * @return the timelines
+     */
+    @NotNull
+    public List<Timeline> getTimelines();
+
     // Paper start
 
     /**

paper-api/src/main/java/org/bukkit/WorldCreator.java

@@ -1,6 +1,13 @@
 package org.bukkit;
 
 import com.google.common.base.Preconditions;
+import io.papermc.paper.registry.RegistryKey;
+import io.papermc.paper.registry.TypedKey;
+import io.papermc.paper.world.Timeline;
+import io.papermc.paper.world.WorldClock;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
 import java.util.Random;
 import org.bukkit.command.CommandSender;
 import org.bukkit.generator.BiomeProvider;
@@ -25,6 +32,8 @@ public class WorldCreator {
     private String generatorSettings = "";
     private boolean hardcore = false;
     private boolean bonusChest = false;
+    private TypedKey<WorldClock> clock = null;
+    private List<TypedKey<Timeline>> timelines = null;
 
     /**
      * Creates an empty WorldCreationOptions for the given world name.
@@ -152,6 +161,8 @@ public class WorldCreator {
         generateStructures = world.canGenerateStructures();
         hardcore = world.isHardcore();
         bonusChest = world.hasBonusChest();
+        clock = world.getClock() == null ? null : TypedKey.create(RegistryKey.WORLD_CLOCK, world.getClock().getKey());
+        timelines = world.getTimelines().stream().map(timeline -> TypedKey.create(RegistryKey.TIMELINE, timeline.getKey())).toList();
 
         return this;
     }
@@ -175,6 +186,8 @@ public class WorldCreator {
         generatorSettings = creator.generatorSettings();
         hardcore = creator.hardcore();
         bonusChest = creator.bonusChest();
+        clock = creator.clock();
+        timelines = creator.timelines() == null ? null : new ArrayList<>(creator.timelines());
 
         return this;
     }
@@ -513,6 +526,56 @@ public class WorldCreator {
         return bonusChest;
     }
 
+    /**
+     * Sets the clock that will be used by this world.
+     * <p>
+     * If unset, the clock from the selected environment's dimension type will be used.
+     * If set, this overrides the selected environment dimension type's clock.
+     *
+     * @param clock the clock, or null to use the environment default
+     * @return This object, for chaining
+     */
+    @NotNull
+    public WorldCreator clock(@Nullable TypedKey<WorldClock> clock) {
+        this.clock = clock;
+        return this;
+    }
+
+    /**
+     * Gets the clock override that will be used by this world.
+     *
+     * @return the clock override, or null to use the environment default
+     */
+    @Nullable
+    public TypedKey<WorldClock> clock() {
+        return this.clock;
+    }
+
+    /**
+     * Sets the timelines that will be used by this world's dimension type.
+     * <p>
+     * If unset, the timelines from the selected environment's dimension type will be used.
+     * Passing an empty collection will create or load the world with no timelines.
+     *
+     * @param timelines the timelines, or null to use the environment default
+     * @return This object, for chaining
+     */
+    @NotNull
+    public WorldCreator timelines(@Nullable Collection<TypedKey<Timeline>> timelines) {
+        this.timelines = timelines == null ? null : new ArrayList<>(timelines);
+        return this;
+    }
+
+    /**
+     * Gets the timeline overrides that will be used by this world's dimension type.
+     *
+     * @return the timeline overrides, or null to use the environment default
+     */
+    @Nullable
+    public List<TypedKey<Timeline>> timelines() {
+        return this.timelines == null ? null : List.copyOf(this.timelines);
+    }
+
     /**
      * Creates a world with the specified options.
      * <p>

paper-api/src/main/java/org/bukkit/event/world/ClockTimeSkipEvent.java

@@ -0,0 +1,110 @@
+package org.bukkit.event.world;
+
+import io.papermc.paper.world.WorldClock;
+import org.bukkit.event.Cancellable;
+import org.bukkit.event.Event;
+import org.bukkit.event.HandlerList;
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Called when the time skips for a world clock.
+ * <p>
+ * If the event is cancelled the time will not change.
+ */
+public class ClockTimeSkipEvent extends Event implements Cancellable {
+
+    private static final HandlerList HANDLER_LIST = new HandlerList();
+
+    private final WorldClock clock;
+    private final SkipReason skipReason;
+    private long skipAmount;
+
+    private boolean cancelled;
+
+    @ApiStatus.Internal
+    public ClockTimeSkipEvent(@NotNull WorldClock clock, @NotNull SkipReason skipReason, long skipAmount) {
+        this.clock = clock;
+        this.skipReason = skipReason;
+        this.skipAmount = skipAmount;
+    }
+
+    /**
+     * Gets the clock whose time is changing.
+     *
+     * @return the clock, or null if the change does not target a specific clock
+     */
+    @NotNull
+    public WorldClock getClock() {
+        return this.clock;
+    }
+
+    /**
+     * Gets the reason why the time has skipped.
+     *
+     * @return a SkipReason value detailing why the time has skipped
+     */
+    @NotNull
+    public SkipReason getSkipReason() {
+        return this.skipReason;
+    }
+
+    /**
+     * Gets the amount of time that was skipped.
+     *
+     * @return Amount of time skipped
+     */
+    public long getSkipAmount() {
+        return this.skipAmount;
+    }
+
+    /**
+     * Sets the amount of time to skip.
+     *
+     * @param skipAmount Amount of time to skip
+     */
+    public void setSkipAmount(long skipAmount) {
+        this.skipAmount = skipAmount;
+    }
+
+    @Override
+    public boolean isCancelled() {
+        return this.cancelled;
+    }
+
+    @Override
+    public void setCancelled(boolean cancel) {
+        this.cancelled = cancel;
+    }
+
+    @NotNull
+    @Override
+    public HandlerList getHandlers() {
+        return HANDLER_LIST;
+    }
+
+    @NotNull
+    public static HandlerList getHandlerList() {
+        return HANDLER_LIST;
+    }
+
+    /**
+     * An enum specifying the reason the time skipped.
+     */
+    public enum SkipReason {
+
+        /**
+         * When time is changed using the vanilla /time command.
+         */
+        COMMAND,
+        /**
+         * When time is changed by a plugin.
+         */
+        CUSTOM,
+        /**
+         * When time is changed by all players sleeping in their beds and the
+         * night skips.
+         */
+        NIGHT_SKIP
+    }
+}

paper-api/src/main/java/org/bukkit/event/world/TimeSkipEvent.java

@@ -1,7 +1,7 @@
 package org.bukkit.event.world;
 
+import io.papermc.paper.world.WorldClock;
 import org.bukkit.World;
-import org.bukkit.event.Cancellable;
 import org.bukkit.event.HandlerList;
 import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
@@ -11,59 +11,26 @@ import org.jetbrains.annotations.NotNull;
  * <p>
  * If the event is cancelled the time will not change.
  */
-// TODO - snapshot - 26.1 API needed for clock!
-public class TimeSkipEvent extends WorldEvent implements Cancellable {
+public class TimeSkipEvent extends ClockTimeSkipEvent {
 
     private static final HandlerList HANDLER_LIST = new HandlerList();
 
-    private final SkipReason skipReason;
-    private long skipAmount;
-
-    private boolean cancelled;
+    private final World world;
 
     @ApiStatus.Internal
-    public TimeSkipEvent(@NotNull World world, @NotNull SkipReason skipReason, long skipAmount) {
-        super(world);
-        this.skipReason = skipReason;
-        this.skipAmount = skipAmount;
+    public TimeSkipEvent(@NotNull World world, @NotNull WorldClock clock, @NotNull SkipReason skipReason, long skipAmount) {
+        super(clock, skipReason, skipAmount);
+        this.world = world;
     }
 
     /**
-     * Gets the reason why the time has skipped.
+     * Returns the world that time is skipped in.
      *
-     * @return a SkipReason value detailing why the time has skipped
+     * @return world that time is skipped in
      */
     @NotNull
-    public SkipReason getSkipReason() {
-        return this.skipReason;
-    }
-
-    /**
-     * Gets the amount of time that was skipped.
-     *
-     * @return Amount of time skipped
-     */
-    public long getSkipAmount() {
-        return this.skipAmount;
-    }
-
-    /**
-     * Sets the amount of time to skip.
-     *
-     * @param skipAmount Amount of time to skip
-     */
-    public void setSkipAmount(long skipAmount) {
-        this.skipAmount = skipAmount;
-    }
-
-    @Override
-    public boolean isCancelled() {
-        return this.cancelled;
-    }
-
-    @Override
-    public void setCancelled(boolean cancel) {
-        this.cancelled = cancel;
+    public World getWorld() {
+        return world;
     }
 
     @NotNull
@@ -76,24 +43,4 @@ public class TimeSkipEvent extends WorldEvent implements Cancellable {
     public static HandlerList getHandlerList() {
         return HANDLER_LIST;
     }
-
-    /**
-     * An enum specifying the reason the time skipped.
-     */
-    public enum SkipReason {
-
-        /**
-         * When time is changed using the vanilla /time command.
-         */
-        COMMAND,
-        /**
-         * When time is changed by a plugin.
-         */
-        CUSTOM,
-        /**
-         * When time is changed by all players sleeping in their beds and the
-         * night skips.
-         */
-        NIGHT_SKIP
-    }
 }

paper-generator/src/main/java/io/papermc/generator/registry/RegistryEntries.java

@@ -17,9 +17,13 @@ import io.papermc.paper.registry.data.JukeboxSongRegistryEntry;
 import io.papermc.paper.registry.data.PaintingVariantRegistryEntry;
 import io.papermc.paper.registry.data.PigVariantRegistryEntry;
 import io.papermc.paper.registry.data.SoundEventRegistryEntry;
+import io.papermc.paper.registry.data.TimelineRegistryEntry;
 import io.papermc.paper.registry.data.WolfVariantRegistryEntry;
+import io.papermc.paper.registry.data.WorldClockRegistryEntry;
 import io.papermc.paper.registry.data.ZombieNautilusVariantRegistryEntry;
 import io.papermc.paper.registry.data.dialog.DialogRegistryEntry;
+import io.papermc.paper.world.Timeline;
+import io.papermc.paper.world.WorldClock;
 import java.lang.reflect.Field;
 import java.lang.reflect.Modifier;
 import java.lang.reflect.Type;
@@ -65,6 +69,7 @@ import net.minecraft.world.item.alchemy.Potions;
 import net.minecraft.world.item.enchantment.Enchantments;
 import net.minecraft.world.item.equipment.trim.TrimMaterials;
 import net.minecraft.world.item.equipment.trim.TrimPatterns;
+import net.minecraft.world.clock.WorldClocks;
 import net.minecraft.world.level.biome.Biomes;
 import net.minecraft.world.level.block.Blocks;
 import net.minecraft.world.level.block.entity.BannerPatterns;
@@ -72,6 +77,7 @@ import net.minecraft.world.level.gamerules.GameRules;
 import net.minecraft.world.level.levelgen.structure.BuiltinStructures;
 import net.minecraft.world.level.material.Fluids;
 import net.minecraft.world.level.saveddata.maps.MapDecorationTypes;
+import net.minecraft.world.timeline.Timelines;
 import org.bukkit.Art;
 import org.bukkit.Fluid;
 import org.bukkit.GameEvent;
@@ -201,7 +207,9 @@ public final class RegistryEntries {
         entry(Registries.PIG_VARIANT, PigVariants.class, Pig.Variant.class).writableApiRegistryBuilder(PigVariantRegistryEntry.Builder.class, "PaperPigVariantRegistryEntry.PaperBuilder"),
         entry(Registries.PIG_SOUND_VARIANT, PigSoundVariants.class, Pig.SoundVariant.class),
         entry(Registries.ZOMBIE_NAUTILUS_VARIANT, ZombieNautilusVariants.class, ZombieNautilus.Variant.class).writableApiRegistryBuilder(ZombieNautilusVariantRegistryEntry.Builder.class, "PaperZombieNautilusVariantRegistryEntry.PaperBuilder"),
-        entry(Registries.DIALOG, Dialogs.class, Dialog.class, "Paper").allowDirect().writableApiRegistryBuilder(DialogRegistryEntry.Builder.class, "PaperDialogRegistryEntry.PaperBuilder")
+        entry(Registries.DIALOG, Dialogs.class, Dialog.class, "Paper").allowDirect().writableApiRegistryBuilder(DialogRegistryEntry.Builder.class, "PaperDialogRegistryEntry.PaperBuilder"),
+        entry(Registries.WORLD_CLOCK, WorldClocks.class, WorldClock.class).writableApiRegistryBuilder(WorldClockRegistryEntry.Builder.class, "PaperWorldClockRegistryEntry.PaperBuilder").delayed(),
+        entry(Registries.TIMELINE, Timelines.class, Timeline.class).writableApiRegistryBuilder(TimelineRegistryEntry.Builder.class, "PaperTimelineRegistryEntry.PaperBuilder").delayed()
     );
 
     public static final List<RegistryEntry<?>> API_ONLY = List.of(

paper-server/patches/features/0001-Moonrise-optimisation-patches.patch

@@ -23838,7 +23838,7 @@ index 3c1490ac7c259da04031db2f170e0c0a5f512191..470d7c770ae9d045b97e2df145cfe3cf
          }
      }
 diff --git a/net/minecraft/server/MinecraftServer.java b/net/minecraft/server/MinecraftServer.java
-index ceb6d955ef275802e549fb9d3e653cc3dda92dad..b4bd3b788a86458ece580693baf164195b730e22 100644
+index 2d9106648f8921ef60c2a24e166d17eb8ce01b48..cea3bd30d326ece39298262401681d77fe064464 100644
 --- a/net/minecraft/server/MinecraftServer.java
 +++ b/net/minecraft/server/MinecraftServer.java
 @@ -191,7 +191,7 @@ import net.minecraft.world.scores.ScoreboardSaveData;
@@ -27004,7 +27004,7 @@ index de75dda2e6f17f0ae6e7f6a5620fd3eac9d389e5..6774d12d04fa848624fb8bf7a3c2b8bc
          List<Entity> passengers = this.entity.getPassengers();
          if (!passengers.equals(this.lastPassengers)) {
 diff --git a/net/minecraft/server/level/ServerLevel.java b/net/minecraft/server/level/ServerLevel.java
-index bc545cb3fc519aa1f5136e420264fea2239fc4c1..3cd2fcc38f3989bb5124ba5bc2f4597103e7a111 100644
+index e17e391862a6b888ed0d0a3c4ab136d9ac47375d..ed52a5e099b74b71ae05f21a4ad0d01dee9c2a60 100644
 --- a/net/minecraft/server/level/ServerLevel.java
 +++ b/net/minecraft/server/level/ServerLevel.java
 @@ -182,7 +182,7 @@ import net.minecraft.world.waypoints.WaypointTransmitter;
@@ -27420,7 +27420,7 @@ index bc545cb3fc519aa1f5136e420264fea2239fc4c1..3cd2fcc38f3989bb5124ba5bc2f45971
          this.getCraftServer().addWorld(this.getWorld()); // CraftBukkit
      }
  
-@@ -607,8 +865,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
+@@ -615,8 +873,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
                                  profiler.push("checkDespawn");
                                  entity.checkDespawn();
                                  profiler.pop();
@@ -27430,7 +27430,7 @@ index bc545cb3fc519aa1f5136e420264fea2239fc4c1..3cd2fcc38f3989bb5124ba5bc2f45971
                                      Entity vehicle = entity.getVehicle();
                                      if (vehicle != null) {
                                          if (!vehicle.isRemoved() && vehicle.hasPassenger(entity)) {
-@@ -632,7 +889,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
+@@ -640,7 +897,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
          }
  
          profiler.push("entityManagement");
@@ -27439,7 +27439,7 @@ index bc545cb3fc519aa1f5136e420264fea2239fc4c1..3cd2fcc38f3989bb5124ba5bc2f45971
          profiler.pop();
          profiler.push("debugSynchronizers");
          if (this.debugSynchronizers.hasAnySubscriberFor(DebugSubscriptions.NEIGHBOR_UPDATES)) {
-@@ -649,7 +906,10 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
+@@ -657,7 +914,10 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
  
      @Override
      public boolean shouldTickBlocksAt(final long chunkPos) {
@@ -27451,7 +27451,7 @@ index bc545cb3fc519aa1f5136e420264fea2239fc4c1..3cd2fcc38f3989bb5124ba5bc2f45971
      }
  
      protected void tickTime() {
-@@ -673,7 +933,60 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
+@@ -681,7 +941,60 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
          this.players.stream().filter(LivingEntity::isSleeping).collect(Collectors.toList()).forEach(player -> player.stopSleepInBed(false, false));
      }
  
@@ -27512,7 +27512,7 @@ index bc545cb3fc519aa1f5136e420264fea2239fc4c1..3cd2fcc38f3989bb5124ba5bc2f45971
          ChunkPos chunkPos = chunk.getPos();
          int minX = chunkPos.getMinBlockX();
          int minZ = chunkPos.getMinBlockZ();
-@@ -682,7 +995,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
+@@ -690,7 +1003,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
  
          if (!this.paperConfig().environment.disableIceAndSnow) { // Paper - Option to disable ice and snow
          for (int i = 0; i < tickSpeed; i++) {
@@ -27521,7 +27521,7 @@ index bc545cb3fc519aa1f5136e420264fea2239fc4c1..3cd2fcc38f3989bb5124ba5bc2f45971
                  this.tickPrecipitation(this.getBlockRandomPos(minX, 0, minZ, 15));
              }
          }
-@@ -690,31 +1003,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
+@@ -698,31 +1011,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
  
          profiler.popPush("tickBlocks");
          if (tickSpeed > 0) {
@@ -27554,7 +27554,7 @@ index bc545cb3fc519aa1f5136e420264fea2239fc4c1..3cd2fcc38f3989bb5124ba5bc2f45971
          }
  
          profiler.pop();
-@@ -1037,6 +1326,12 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
+@@ -1045,6 +1334,12 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
          if (fluidState.is(type)) {
              fluidState.tick(this, pos, blockState);
          }
@@ -27567,7 +27567,7 @@ index bc545cb3fc519aa1f5136e420264fea2239fc4c1..3cd2fcc38f3989bb5124ba5bc2f45971
      }
  
      private void tickBlock(final BlockPos pos, final Block type) {
-@@ -1044,6 +1339,12 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
+@@ -1052,6 +1347,12 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
          if (state.is(type)) {
              state.tick(this, pos, this.random);
          }
@@ -27580,7 +27580,7 @@ index bc545cb3fc519aa1f5136e420264fea2239fc4c1..3cd2fcc38f3989bb5124ba5bc2f45971
      }
  
      // Paper start - log detailed entity tick information
-@@ -1128,6 +1429,11 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
+@@ -1136,6 +1437,11 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
      }
  
      public void save(final @Nullable ProgressListener progressListener, final boolean flush, final boolean noSave) {
@@ -27592,7 +27592,7 @@ index bc545cb3fc519aa1f5136e420264fea2239fc4c1..3cd2fcc38f3989bb5124ba5bc2f45971
          ServerChunkCache chunkSource = this.getChunkSource();
          if (!noSave) {
              new org.bukkit.event.world.WorldSaveEvent(this.getWorld()).callEvent(); // CraftBukkit
-@@ -1140,13 +1446,18 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
+@@ -1148,13 +1454,18 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
                  progressListener.progressStage(Component.translatable("menu.savingChunks"));
              }
  
@@ -27616,7 +27616,7 @@ index bc545cb3fc519aa1f5136e420264fea2239fc4c1..3cd2fcc38f3989bb5124ba5bc2f45971
      }
  
      private void saveLevelData(final boolean sync) {
-@@ -1267,7 +1578,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
+@@ -1275,7 +1586,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
              this.removePlayerImmediately((ServerPlayer)existing, Entity.RemovalReason.DISCARDED);
          }
  
@@ -27625,7 +27625,7 @@ index bc545cb3fc519aa1f5136e420264fea2239fc4c1..3cd2fcc38f3989bb5124ba5bc2f45971
      }
  
      // CraftBukkit start
-@@ -1298,7 +1609,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
+@@ -1306,7 +1617,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
              }
              // CraftBukkit end
  
@@ -27634,7 +27634,7 @@ index bc545cb3fc519aa1f5136e420264fea2239fc4c1..3cd2fcc38f3989bb5124ba5bc2f45971
          }
      }
  
-@@ -1309,7 +1620,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
+@@ -1317,7 +1628,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
  
      public boolean tryAddFreshEntityWithPassengers(final Entity entity, final org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason reason) {
          // CraftBukkit end
@@ -27643,7 +27643,7 @@ index bc545cb3fc519aa1f5136e420264fea2239fc4c1..3cd2fcc38f3989bb5124ba5bc2f45971
              return false;
          } else {
              this.addFreshEntityWithPassengers(entity, reason); // CraftBukkit
-@@ -2103,7 +2414,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
+@@ -2111,7 +2422,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
                  }
              }
  
@@ -27652,7 +27652,7 @@ index bc545cb3fc519aa1f5136e420264fea2239fc4c1..3cd2fcc38f3989bb5124ba5bc2f45971
              output.write(String.format(Locale.ROOT, "block_entity_tickers: %d\n", this.blockEntityTickers.size()));
              output.write(String.format(Locale.ROOT, "block_ticks: %d\n", this.getBlockTicks().count()));
              output.write(String.format(Locale.ROOT, "fluid_ticks: %d\n", this.getFluidTicks().count()));
-@@ -2121,13 +2432,13 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
+@@ -2129,13 +2440,13 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
          Path chunks = rootDir.resolve("chunks.csv");
  
          try (Writer output = Files.newBufferedWriter(chunks)) {
@@ -27668,7 +27668,7 @@ index bc545cb3fc519aa1f5136e420264fea2239fc4c1..3cd2fcc38f3989bb5124ba5bc2f45971
          }
  
          Path entities = rootDir.resolve("entities.csv");
-@@ -2222,8 +2533,8 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
+@@ -2230,8 +2541,8 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
              Locale.ROOT,
              "players: %s, entities: %s [%s], block_entities: %d [%s], block_ticks: %d, fluid_ticks: %d, chunk_source: %s",
              this.players.size(),
@@ -27679,7 +27679,7 @@ index bc545cb3fc519aa1f5136e420264fea2239fc4c1..3cd2fcc38f3989bb5124ba5bc2f45971
              this.blockEntityTickers.size(),
              getTypeCount(this.blockEntityTickers, TickingBlockEntity::getType),
              this.getBlockTicks().count(),
-@@ -2256,15 +2567,25 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
+@@ -2264,15 +2575,25 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
      @Override
      public LevelEntityGetter<Entity> getEntities() {
          org.spigotmc.AsyncCatcher.catchOp("Chunk getEntities call"); // Spigot
@@ -27708,7 +27708,7 @@ index bc545cb3fc519aa1f5136e420264fea2239fc4c1..3cd2fcc38f3989bb5124ba5bc2f45971
      }
  
      public void startTickingChunk(final LevelChunk levelChunk) {
-@@ -2281,8 +2602,8 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
+@@ -2289,8 +2610,8 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
  
      public void waitForEntities(final ChunkPos centerChunk, final int radius) {
          List<ChunkPos> chunks = ChunkPos.rangeClosed(centerChunk, radius).toList();
@@ -27719,7 +27719,7 @@ index bc545cb3fc519aa1f5136e420264fea2239fc4c1..3cd2fcc38f3989bb5124ba5bc2f45971
  
              for (ChunkPos chunk : chunks) {
                  if (!this.areEntitiesLoaded(chunk.pack())) {
-@@ -2303,28 +2624,38 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
+@@ -2311,28 +2632,38 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
      @Override
      public void close() throws IOException {
          super.close();
@@ -27764,7 +27764,7 @@ index bc545cb3fc519aa1f5136e420264fea2239fc4c1..3cd2fcc38f3989bb5124ba5bc2f45971
      }
  
      public boolean anyPlayerCloseEnoughForSpawning(final BlockPos pos) {
-@@ -2341,7 +2672,10 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
+@@ -2349,7 +2680,10 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
      }
  
      public boolean canSpawnEntitiesInChunk(final ChunkPos pos) {
@@ -27776,7 +27776,7 @@ index bc545cb3fc519aa1f5136e420264fea2239fc4c1..3cd2fcc38f3989bb5124ba5bc2f45971
      }
  
      @Override
-@@ -2389,7 +2723,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
+@@ -2397,7 +2731,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
      public CrashReportCategory fillReportDetails(final CrashReport report) {
          CrashReportCategory category = super.fillReportDetails(report);
          WeatherData weatherData = this.getWeatherData();
@@ -30053,7 +30053,7 @@ index e07a7bda45146686a6ac2d20507df9fc8630514f..f84e651e2a34e76a0a71993332e4be1b
  
      // Paper start - Affects Spawning API
 diff --git a/net/minecraft/world/level/Level.java b/net/minecraft/world/level/Level.java
-index 81c3f9f04040b6cfa014ce55e517bd9b374ec252..0958fe0438c3e934b885acf78a0f8003ef8bb694 100644
+index 506efca7cec0e268f03c6c070d69afbc853aaf03..995b51d859316c6128b30d930e58dd47224514b2 100644
 --- a/net/minecraft/world/level/Level.java
 +++ b/net/minecraft/world/level/Level.java
 @@ -87,6 +87,7 @@ import net.minecraft.world.level.storage.LevelData;
@@ -30941,7 +30941,7 @@ index 81c3f9f04040b6cfa014ce55e517bd9b374ec252..0958fe0438c3e934b885acf78a0f8003
  
      public <T extends Entity> boolean hasEntities(final EntityTypeTest<Entity, T> type, final AABB bb, final Predicate<? super T> selector) {
          Profiler.get().incrementCounter("hasEntities");
-@@ -1465,13 +2169,7 @@ public abstract class Level implements LevelAccessor, AutoCloseable {
+@@ -1469,13 +2173,7 @@ public abstract class Level implements LevelAccessor, AutoCloseable {
  
      // Paper start - allow patching this logic
      public final int getEntityCount() {

paper-server/patches/features/0005-Entity-Activation-Range-2.0.patch

@@ -354,10 +354,10 @@ index 0000000000000000000000000000000000000000..ce6b57eeeeb1bd652f4bb53c19dcfbc0
 +    }
 +}
 diff --git a/net/minecraft/server/level/ServerLevel.java b/net/minecraft/server/level/ServerLevel.java
-index 3cd2fcc38f3989bb5124ba5bc2f4597103e7a111..6d847ff3646b27fe9bc75e792d813a7f611ab3e5 100644
+index ed52a5e099b74b71ae05f21a4ad0d01dee9c2a60..9f43d29aa4fecb03d6ef49e71e4de846dca187de 100644
 --- a/net/minecraft/server/level/ServerLevel.java
 +++ b/net/minecraft/server/level/ServerLevel.java
-@@ -857,6 +857,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
+@@ -865,6 +865,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
                  profiler.pop();
              }
  
@@ -365,7 +365,7 @@ index 3cd2fcc38f3989bb5124ba5bc2f4597103e7a111..6d847ff3646b27fe9bc75e792d813a7f
              this.entityTickList
                  .forEach(
                      entity -> {
-@@ -1373,12 +1374,15 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
+@@ -1381,12 +1382,15 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
          entity.totalEntityAge++; // Paper - age-like counter for all entities
          profiler.push(entity.typeHolder()::getRegisteredName);
          profiler.incrementCounter("tickNonPassenger");
@@ -382,7 +382,7 @@ index 3cd2fcc38f3989bb5124ba5bc2f4597103e7a111..6d847ff3646b27fe9bc75e792d813a7f
          }
          // Paper start - log detailed entity tick information
          } finally {
-@@ -1389,7 +1393,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
+@@ -1397,7 +1401,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
          // Paper end - log detailed entity tick information
      }
  
@@ -391,7 +391,7 @@ index 3cd2fcc38f3989bb5124ba5bc2f4597103e7a111..6d847ff3646b27fe9bc75e792d813a7f
          if (entity.isRemoved() || entity.getVehicle() != vehicle) {
              entity.stopRiding();
          } else if (entity instanceof Player || this.entityTickList.contains(entity)) {
-@@ -1399,12 +1403,21 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
+@@ -1407,12 +1411,21 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
              ProfilerFiller profiler = Profiler.get();
              profiler.push(entity.typeHolder()::getRegisteredName);
              profiler.incrementCounter("tickPassenger");
@@ -816,7 +816,7 @@ index 3a590d4dc980a2912e9cc043d8c8db4cf9d60803..06ab7c48b18c03af494ab10fc2b584ce
 +
  }
 diff --git a/net/minecraft/world/level/Level.java b/net/minecraft/world/level/Level.java
-index 0958fe0438c3e934b885acf78a0f8003ef8bb694..31c7223d2d01573c24d4ad83737fa2c2752db028 100644
+index 995b51d859316c6128b30d930e58dd47224514b2..329aef0e55664fbdd98c84d4d7cee74cd633e9c3 100644
 --- a/net/minecraft/world/level/Level.java
 +++ b/net/minecraft/world/level/Level.java
 @@ -155,6 +155,12 @@ public abstract class Level implements LevelAccessor, AutoCloseable, ca.spottedl

paper-server/patches/features/0016-Add-Alternate-Current-redstone-implementation.patch

@@ -2326,7 +2326,7 @@ index 0000000000000000000000000000000000000000..298076a0db4e6ee6e4775ac43bf749d9
 +    }
 +}
 diff --git a/net/minecraft/server/level/ServerLevel.java b/net/minecraft/server/level/ServerLevel.java
-index 6d847ff3646b27fe9bc75e792d813a7f611ab3e5..cfc30654917703a9278143a2c36d37eb719ee061 100644
+index 9f43d29aa4fecb03d6ef49e71e4de846dca187de..2e76ab96c66fd39b5e6619c3dbc75559d5c9b04a 100644
 --- a/net/minecraft/server/level/ServerLevel.java
 +++ b/net/minecraft/server/level/ServerLevel.java
 @@ -232,6 +232,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
@@ -2337,7 +2337,7 @@ index 6d847ff3646b27fe9bc75e792d813a7f611ab3e5..cfc30654917703a9278143a2c36d37eb
  
      @Override
      public @Nullable LevelChunk getChunkIfLoaded(int x, int z) {
-@@ -2766,6 +2767,13 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
+@@ -2774,6 +2775,13 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
          return this.debugSynchronizers;
      }
  
@@ -2352,10 +2352,10 @@ index 6d847ff3646b27fe9bc75e792d813a7f611ab3e5..cfc30654917703a9278143a2c36d37eb
          return toLevel.dimension() != Level.NETHER || this.getGameRules().get(GameRules.ALLOW_ENTERING_NETHER_USING_PORTALS);
      }
 diff --git a/net/minecraft/world/level/Level.java b/net/minecraft/world/level/Level.java
-index 31c7223d2d01573c24d4ad83737fa2c2752db028..8df070a7135411806d42ea692b566c4d8389a47b 100644
+index 329aef0e55664fbdd98c84d4d7cee74cd633e9c3..b9e07d5bd36993c5ac83b843866fabbea71c4281 100644
 --- a/net/minecraft/world/level/Level.java
 +++ b/net/minecraft/world/level/Level.java
-@@ -2152,6 +2152,17 @@ public abstract class Level implements LevelAccessor, AutoCloseable, ca.spottedl
+@@ -2156,6 +2156,17 @@ public abstract class Level implements LevelAccessor, AutoCloseable, ca.spottedl
          return this.palettedContainerFactory;
      }
  

paper-server/patches/features/0020-Incremental-chunk-and-player-saving.patch

@@ -5,7 +5,7 @@ Subject: [PATCH] Incremental chunk and player saving
 
 
 diff --git a/net/minecraft/server/MinecraftServer.java b/net/minecraft/server/MinecraftServer.java
-index def29f67aa4d901fd61cb546f65b763b3da09131..a3edf217dd2ffce19dc1111402975ba12bb86bad 100644
+index 9a014a1a198293c9ce02354d8128cb19666055b8..c6691f02a1b2c1540b959fcc07eb8390906541ec 100644
 --- a/net/minecraft/server/MinecraftServer.java
 +++ b/net/minecraft/server/MinecraftServer.java
 @@ -958,7 +958,7 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
@@ -94,10 +94,10 @@ index def29f67aa4d901fd61cb546f65b763b3da09131..a3edf217dd2ffce19dc1111402975ba1
          ProfilerFiller profiler = Profiler.get();
          this.server.spark.executeMainThreadTasks(); // Paper - spark
 diff --git a/net/minecraft/server/level/ServerLevel.java b/net/minecraft/server/level/ServerLevel.java
-index cfc30654917703a9278143a2c36d37eb719ee061..78021db10860396fef4eb2e01926fbad123916fa 100644
+index 2e76ab96c66fd39b5e6619c3dbc75559d5c9b04a..b4a3c61a370939db94d57a911cfa5cfa1008a93a 100644
 --- a/net/minecraft/server/level/ServerLevel.java
 +++ b/net/minecraft/server/level/ServerLevel.java
-@@ -1441,6 +1441,15 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
+@@ -1449,6 +1449,15 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
      public boolean mayInteract(final Entity entity, final BlockPos pos) {
          return !(entity instanceof Player player && (this.server.isUnderSpawnProtection(this, pos, player) || !this.getWorldBorder().isWithinBounds(pos)));
      }

paper-server/patches/features/0029-Optimize-Hoppers.patch

@@ -48,7 +48,7 @@ index 0000000000000000000000000000000000000000..24a2090e068ad3c0d08705050944abdf
 +    }
 +}
 diff --git a/net/minecraft/server/MinecraftServer.java b/net/minecraft/server/MinecraftServer.java
-index 2b6717833b56c3e33f3ac656a376dd5c841dc1bc..2142757965b7345a011a92de08038473fa8ae320 100644
+index fbd70bcdc2efb42505fd5b3e5a6f703782c4060d..000943733f07cef2e508f78aadf5d28dec70e90c 100644
 --- a/net/minecraft/server/MinecraftServer.java
 +++ b/net/minecraft/server/MinecraftServer.java
 @@ -1836,6 +1836,7 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa

paper-server/patches/features/0030-Anti-Xray.patch

@@ -155,7 +155,7 @@ index a94e6ca1d396b6b0781de5d550c4a804274ee003..a1018e9ca9dfb978d6e6633577abd7d5
  
      private ClientboundLevelChunkWithLightPacket(final RegistryFriendlyByteBuf input) {
 diff --git a/net/minecraft/server/level/ServerLevel.java b/net/minecraft/server/level/ServerLevel.java
-index 78021db10860396fef4eb2e01926fbad123916fa..3f02da2014ed8e4169f4bb819b4d9e61154b7b06 100644
+index b4a3c61a370939db94d57a911cfa5cfa1008a93a..be0e0b3a70bde1e2217ba4d3f90031e243d86941 100644
 --- a/net/minecraft/server/level/ServerLevel.java
 +++ b/net/minecraft/server/level/ServerLevel.java
 @@ -630,7 +630,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
@@ -209,7 +209,7 @@ index b69bcaa1e27a4fbe9a9568f3c9e1843167abe1f5..9218322801c41657c00928ef90b0de99
          }
          // Paper end - Send empty chunk
 diff --git a/net/minecraft/world/level/Level.java b/net/minecraft/world/level/Level.java
-index 06451a21c4bfbcd95063f96246013d63f65af8a3..e34e901dce06c6bc6060418593010dcfb38e9396 100644
+index 630aec19b88a519fa4ec382fb2f5e9aebda59208..f765bc3d805de16909b0407da633208bb0dd9edc 100644
 --- a/net/minecraft/world/level/Level.java
 +++ b/net/minecraft/world/level/Level.java
 @@ -145,6 +145,7 @@ public abstract class Level implements LevelAccessor, AutoCloseable, ca.spottedl

paper-server/patches/sources/net/minecraft/gametest/framework/GameTestHelper.java.patch

@@ -0,0 +1,11 @@
+--- a/net/minecraft/gametest/framework/GameTestHelper.java
++++ b/net/minecraft/gametest/framework/GameTestHelper.java
+@@ -929,7 +_,7 @@
+ 
+     public void setTime(final long ticks) {
+         ServerLevel level = this.getLevel();
+-        Holder<WorldClock> clock = level.dimensionType().defaultClock().orElseThrow();
++        Holder<WorldClock> clock = level.getClock().orElseThrow();
+         level.clockManager().setTotalTicks(clock, ticks);
+     }
+ 

paper-server/patches/sources/net/minecraft/server/MinecraftServer.java.patch

@@ -1534,7 +1534,7 @@
                  player.connection.send(new ClientboundEntityEventPacket(player, event));
              }
          } else if (rule == GameRules.LIMITED_CRAFTING || rule == GameRules.IMMEDIATE_RESPAWN) {
-@@ -2131,19 +_,21 @@
+@@ -2131,18 +_,19 @@
                  ? ClientboundGameEventPacket.LIMITED_CRAFTING
                  : ClientboundGameEventPacket.IMMEDIATE_RESPAWN;
              ClientboundGameEventPacket packet = new ClientboundGameEventPacket(eventType, (Boolean)value ? 1.0F : 0.0F);
@@ -1556,10 +1556,8 @@
 -            this.updateMobSpawningFlags();
 +            level.setSpawnSettings(level.isSpawningMonsters()); // Paper - per-world game rules
          } else if (rule == GameRules.ADVANCE_TIME) {
-+            // TODO - snapshot - time handling
              this.getPlayerList().broadcastAll(this.clockManager().createFullSyncPacket());
          }
-     }
 @@ -2157,12 +_,14 @@
          return this.savedDataStorage;
      }

paper-server/patches/sources/net/minecraft/server/commands/TimeCommand.java.patch

@@ -1,67 +1,56 @@
 --- a/net/minecraft/server/commands/TimeCommand.java
 +++ b/net/minecraft/server/commands/TimeCommand.java
-@@ -170,23 +_,61 @@
+@@ -169,16 +_,24 @@
+         }
      }
  
++    // Paper start - time skip event
      private static int setTotalTicks(final CommandSourceStack source, final Holder<WorldClock> clock, final int totalTicks) {
-+        // Paper start
-+        // TODO - snapshot - 26.1
-+        for (net.minecraft.server.level.ServerLevel level : io.papermc.paper.configuration.GlobalConfiguration.get().commands.timeCommandAffectsAllWorlds ? source.getServer().getAllLevels() : java.util.List.of(source.getLevel())) {
-+            long currentTime = level.clockManager().getTotalTicks(clock);
-+            org.bukkit.event.world.TimeSkipEvent event = new org.bukkit.event.world.TimeSkipEvent(level.getWorld(), org.bukkit.event.world.TimeSkipEvent.SkipReason.COMMAND, totalTicks - currentTime);
-+            if (event.callEvent()) {
-+                level.clockManager().setTotalTicks(clock, currentTime + event.getSkipAmount());
-+            }
-+        }
-+        // Paper end
          ServerClockManager clockManager = source.getServer().clockManager();
 -        clockManager.setTotalTicks(clock, totalTicks);
-+        // clockManager.setTotalTicks(clock, totalTicks);
++        long currentTotalTicks = clockManager.getTotalTicks(clock);
++        org.bukkit.event.world.ClockTimeSkipEvent event = org.bukkit.craftbukkit.event.CraftEventFactory.callTimeSkipEvent(clock, totalTicks - currentTotalTicks);
++        if (event.callEvent()) {
++            clockManager.setTotalTicks(clock, currentTotalTicks + event.getSkipAmount());
++        }
          source.sendSuccess(() -> Component.translatable("commands.time.set.absolute", clock.getRegisteredName(), totalTicks), true);
          return totalTicks;
      }
  
      private static int addTime(final CommandSourceStack source, final Holder<WorldClock> clock, final int time) {
-+        // Paper start
-+        // TODO - snapshot - 26.1
-+        for (net.minecraft.server.level.ServerLevel level : io.papermc.paper.configuration.GlobalConfiguration.get().commands.timeCommandAffectsAllWorlds ? source.getServer().getAllLevels() : java.util.List.of(source.getLevel())) {
-+            org.bukkit.event.world.TimeSkipEvent event = new org.bukkit.event.world.TimeSkipEvent(level.getWorld(), org.bukkit.event.world.TimeSkipEvent.SkipReason.COMMAND, time);;
-+            if (event.callEvent()) {
-+                level.clockManager().addTicks(clock, event.getSkipAmount());
-+            }
-+        }
-+        // Paper end
          ServerClockManager clockManager = source.getServer().clockManager();
 -        clockManager.addTicks(clock, time);
-+        // Paper - move up
++        org.bukkit.event.world.ClockTimeSkipEvent event = org.bukkit.craftbukkit.event.CraftEventFactory.callTimeSkipEvent(clock, time);
++        if (event.callEvent()) {
++            clockManager.addTicks(clock, event.getSkipAmount());
++        }
          long totalTicks = clockManager.getTotalTicks(clock);
          source.sendSuccess(() -> Component.translatable("commands.time.set.absolute", clock.getRegisteredName(), totalTicks), true);
          return wrapTime(totalTicks);
-     }
+@@ -186,9 +_,16 @@
  
      private static int setTimeToTimeMarker(final CommandSourceStack source, final Holder<WorldClock> clock, final ResourceKey<ClockTimeMarker> timeMarkerId) throws CommandSyntaxException {
-+        // Paper start
-+        // TODO - snapshot - 26.1
-+        boolean foundMarker = false;
-+        for (net.minecraft.server.level.ServerLevel level : io.papermc.paper.configuration.GlobalConfiguration.get().commands.timeCommandAffectsAllWorlds ? source.getServer().getAllLevels() : java.util.List.of(source.getLevel())) {
-+            java.util.OptionalLong targetTime = level.clockManager().getTotalTicksToTimeMarker(clock, timeMarkerId);
-+            if (targetTime.isEmpty()) {
-+                continue;
-+            }
-+
-+            foundMarker = true;
-+            long currentTime = level.clockManager().getTotalTicks(clock);
-+            long delta = targetTime.getAsLong() - currentTime;
-+            org.bukkit.event.world.TimeSkipEvent event = new org.bukkit.event.world.TimeSkipEvent(level.getWorld(), org.bukkit.event.world.TimeSkipEvent.SkipReason.COMMAND, delta);
-+            if (event.callEvent()) {
-+                level.clockManager().setTotalTicks(clock, currentTime + event.getSkipAmount());
-+            }
-+        }
-+        // Paper end
-+
          ServerClockManager clockManager = source.getServer().clockManager();
 -        if (!clockManager.moveToTimeMarker(clock, timeMarkerId)) {
-+        if (!foundMarker) { // Paper
++        java.util.OptionalLong targetTime = clockManager.getTotalTicksToTimeMarker(clock, timeMarkerId);
++        if (targetTime.isEmpty()) {
              throw ERROR_NO_TIME_MARKER_FOUND.create(clock.getRegisteredName(), timeMarkerId);
          } else {
++            final long currentTime = clockManager.getTotalTicks(clock);
++            final org.bukkit.event.world.ClockTimeSkipEvent event = org.bukkit.craftbukkit.event.CraftEventFactory.callTimeSkipEvent(clock, targetTime.getAsLong() - currentTime);
++            if (event.callEvent()) {
++                clockManager.setTotalTicks(clock, currentTime + event.getSkipAmount());
++            }
++            // Paper end - time skip event
              source.sendSuccess(
+                 () -> Component.translatable("commands.time.set.time_marker", clock.getRegisteredName(), timeMarkerId.identifier().toString()), true
+             );
+@@ -214,7 +_,7 @@
+ 
+     private static Holder<WorldClock> getDefaultClock(final CommandSourceStack source) throws CommandSyntaxException {
+         Holder<DimensionType> dimensionType = source.getLevel().dimensionTypeRegistration();
+-        return dimensionType.value().defaultClock().orElseThrow(() -> ERROR_NO_DEFAULT_CLOCK.create(dimensionType.getRegisteredName()));
++        return source.getLevel().getClock().orElseThrow(() -> ERROR_NO_DEFAULT_CLOCK.create(dimensionType.getRegisteredName())); // Paper - clock override
+     }
+ 
+     private interface ClockGetter {

paper-server/patches/sources/net/minecraft/server/level/ServerLevel.java.patch

@@ -262,24 +262,42 @@
  
      @Deprecated
      @VisibleForTesting
-@@ -354,11 +_,24 @@
+@@ -326,6 +_,13 @@
+     }
+ 
+     @Override
++    public Optional<Holder<WorldClock>> getClock() {
++        return this.serverLevelData.clock()
++            .<Holder<WorldClock>>map(clock -> this.registryAccess().lookupOrThrow(Registries.WORLD_CLOCK).getOrThrow(clock))
++            .or(() -> this.dimensionType().defaultClock());
++    }
++
++    @Override
+     public EnvironmentAttributeSystem environmentAttributes() {
+         return this.environmentAttributes;
+     }
+@@ -353,12 +_,26 @@
+ 
          int percentage = this.getGameRules().get(GameRules.PLAYERS_SLEEPING_PERCENTAGE);
          if (this.sleepStatus.areEnoughSleeping(percentage) && this.sleepStatus.areEnoughDeepSleeping(percentage, this.players)) {
-             Optional<Holder<WorldClock>> defaultClock = this.dimensionType().defaultClock();
-+            org.bukkit.event.world.TimeSkipEvent event = null; // Paper - time skip event
-             if (this.getGameRules().get(GameRules.ADVANCE_TIME) && defaultClock.isPresent()) {
+-            Optional<Holder<WorldClock>> defaultClock = this.dimensionType().defaultClock();
+-            if (this.getGameRules().get(GameRules.ADVANCE_TIME) && defaultClock.isPresent()) {
 -                this.server.clockManager().moveToTimeMarker(defaultClock.get(), ClockTimeMarkers.WAKE_UP_FROM_SLEEP);
++            Optional<Holder<WorldClock>> clock = this.getClock();
++            org.bukkit.event.world.TimeSkipEvent event = null; // Paper - time skip event
++            if (this.getGameRules().get(GameRules.ADVANCE_TIME) && clock.isPresent()) {
 +                // Paper start - time skip event
-+                long currentTime = this.server.clockManager().getTotalTicks(defaultClock.get());
-+                long delta = this.server.clockManager().getTotalTicksToTimeMarker(defaultClock.get(), ClockTimeMarkers.WAKE_UP_FROM_SLEEP).orElse(0L) - currentTime;
++                long currentTime = this.server.clockManager().getTotalTicks(clock.get());
++                long delta = this.server.clockManager().getTotalTicksToTimeMarker(clock.get(), ClockTimeMarkers.WAKE_UP_FROM_SLEEP).orElse(0L) - currentTime;
 +                event = new org.bukkit.event.world.TimeSkipEvent(
 +                    this.getWorld(),
-+                    org.bukkit.event.world.TimeSkipEvent.SkipReason.NIGHT_SKIP,
++                    org.bukkit.craftbukkit.CraftWorldClock.minecraftHolderToBukkit(clock.get()),
++                    org.bukkit.event.world.ClockTimeSkipEvent.SkipReason.NIGHT_SKIP,
 +                    delta
 +                );
 +
 +                if (event.callEvent()) {
-+                    this.server.clockManager().setTotalTicks(defaultClock.get(), currentTime + event.getSkipAmount()); // TODO - snapshot - per world time
++                    this.server.clockManager().setTotalTicks(clock.get(), currentTime + event.getSkipAmount());
 +                }
 +                // Paper end - time skip event
              }

paper-server/patches/sources/net/minecraft/world/clock/ServerClockManager.java.patch

@@ -27,10 +27,18 @@
          this.setDirty();
  
          for (ServerLevel level : this.server.getAllLevels()) {
-@@ -126,7 +_,23 @@
-         return this.getInstance(definition).totalTicks;
+@@ -127,12 +_,29 @@
      }
  
+     public ClientboundSetTimePacket createFullSyncPacket() {
++        // TODO - snapshot: 26.1 per-player time
+         return new ClientboundSetTimePacket(this.getGameTime(), Util.mapValues(this.clocks, clock -> clock.packNetworkState(this.server)));
+     }
+ 
+     private long getGameTime() {
+         return this.server.overworld().getGameTime();
+     }
++
 +    // Paper start
 +    // TODO - snapshot: just make the inner class, fields and getter public
 +    public boolean isPaused(final Holder<WorldClock> definition) {
@@ -44,10 +52,8 @@
 +    public float rate(final Holder<WorldClock> definition) {
 +        return this.getInstance(definition).rate;
 +    }
-+    // Paper end
 +
-     public ClientboundSetTimePacket createFullSyncPacket() {
-+        // TODO - snapshot: 26.1 per-player time
-         return new ClientboundSetTimePacket(this.getGameTime(), Util.mapValues(this.clocks, clock -> clock.packNetworkState(this.server)));
-     }
++    // Paper end
  
+     public boolean isAtTimeMarker(final Holder<WorldClock> clock, final ResourceKey<ClockTimeMarker> timeMarkerId) {
+         ServerClockManager.ClockInstance clockInstance = this.getInstance(clock);

paper-server/patches/sources/net/minecraft/world/entity/ai/village/VillageSiege.java.patch

@@ -1,5 +1,16 @@
 --- a/net/minecraft/world/entity/ai/village/VillageSiege.java
 +++ b/net/minecraft/world/entity/ai/village/VillageSiege.java
+@@ -34,8 +_,8 @@
+     @Override
+     public void tick(final ServerLevel level, final boolean spawnEnemies) {
+         if (!level.isBrightOutside() && spawnEnemies) {
+-            Optional<Holder<WorldClock>> defaultClock = level.dimensionType().defaultClock();
+-            if (defaultClock.isPresent() && level.clockManager().isAtTimeMarker(defaultClock.get(), ClockTimeMarkers.ROLL_VILLAGE_SIEGE)) {
++            Optional<Holder<WorldClock>> clock = level.getClock();
++            if (clock.isPresent() && level.clockManager().isAtTimeMarker(clock.get(), ClockTimeMarkers.ROLL_VILLAGE_SIEGE)) {
+                 this.siegeState = level.getRandom().nextInt(10) == 0 ? VillageSiege.State.SIEGE_TONIGHT : VillageSiege.State.SIEGE_DONE;
+             }
+ 
 @@ -102,11 +_,12 @@
                  zombie.finalizeSpawn(level, level.getCurrentDifficultyAt(zombie.blockPosition()), EntitySpawnReason.EVENT, null);
              } catch (Exception var5) {

paper-server/patches/sources/net/minecraft/world/level/Level.java.patch

@@ -528,6 +528,26 @@
              this.getChunkAt(pos).addAndRegisterBlockEntity(blockEntity);
          }
      }
+@@ -883,7 +_,7 @@
+     }
+ 
+     public long getDefaultClockTime() {
+-        return this.getClockTimeTicks(this.dimensionType().defaultClock());
++        return this.getClockTimeTicks(this.getClock());
+     }
+ 
+     private long getClockTimeTicks(final Optional<? extends Holder<WorldClock>> clock) {
+@@ -1032,6 +_,10 @@
+         return this.dimensionTypeRegistration;
+     }
+ 
++    public Optional<Holder<WorldClock>> getClock() {
++        return this.dimensionType().defaultClock();
++    }
++
+     public ResourceKey<Level> dimension() {
+         return this.dimension;
+     }
 @@ -1110,7 +_,8 @@
          BLOCK("block"),
          MOB("mob"),

paper-server/patches/sources/net/minecraft/world/timeline/Timeline.java.patch

@@ -0,0 +1,23 @@
+--- a/net/minecraft/world/timeline/Timeline.java
++++ b/net/minecraft/world/timeline/Timeline.java
+@@ -49,7 +_,7 @@
+     public static final Codec<Timeline> NETWORK_CODEC = DIRECT_CODEC.xmap(Timeline::filterSyncableTracks, Timeline::filterSyncableTracks);
+     private final Holder<WorldClock> clock;
+     private final Optional<Integer> periodTicks;
+-    private final Map<EnvironmentAttribute<?>, AttributeTrack<?, ?>> tracks;
++    public final Map<EnvironmentAttribute<?>, AttributeTrack<?, ?>> tracks;
+     private final Map<ResourceKey<ClockTimeMarker>, Timeline.TimeMarkerInfo> timeMarkers;
+ 
+     private static Timeline filterSyncableTracks(final Timeline timeline) {
+@@ -179,6 +_,11 @@
+             KeyframeTrack.Builder<Argument> argumentTrack = new KeyframeTrack.Builder<>();
+             builder.accept(argumentTrack);
+             this.tracks.put(attribute, new AttributeTrack<>(modifier, argumentTrack.build()));
++            return this;
++        }
++
++        public Timeline.Builder addTracks(final Map<EnvironmentAttribute<?>, AttributeTrack<?, ?>> tracks) {
++            this.tracks.putAll(tracks);
+             return this;
+         }
+ 

paper-server/src/main/java/io/papermc/paper/registry/PaperRegistries.java

@@ -19,12 +19,16 @@ import io.papermc.paper.registry.data.PaperJukeboxSongRegistryEntry;
 import io.papermc.paper.registry.data.PaperPaintingVariantRegistryEntry;
 import io.papermc.paper.registry.data.PaperPigVariantRegistryEntry;
 import io.papermc.paper.registry.data.PaperSoundEventRegistryEntry;
+import io.papermc.paper.registry.data.PaperTimelineRegistryEntry;
 import io.papermc.paper.registry.data.PaperWolfVariantRegistryEntry;
+import io.papermc.paper.registry.data.PaperWorldClockRegistryEntry;
 import io.papermc.paper.registry.data.PaperZombieNautilusVariantRegistryEntry;
 import io.papermc.paper.registry.data.dialog.PaperDialogRegistryEntry;
 import io.papermc.paper.registry.entry.RegistryEntry;
 import io.papermc.paper.registry.entry.RegistryEntryMeta;
 import io.papermc.paper.registry.tag.TagKey;
+import io.papermc.paper.world.Timeline;
+import io.papermc.paper.world.WorldClock;
 import java.util.Collections;
 import java.util.IdentityHashMap;
 import java.util.List;
@@ -52,6 +56,8 @@ import org.bukkit.craftbukkit.CraftGameRule;
 import org.bukkit.craftbukkit.CraftJukeboxSong;
 import org.bukkit.craftbukkit.CraftMusicInstrument;
 import org.bukkit.craftbukkit.CraftSound;
+import org.bukkit.craftbukkit.CraftTimeline;
+import org.bukkit.craftbukkit.CraftWorldClock;
 import org.bukkit.craftbukkit.attribute.CraftAttribute;
 import org.bukkit.craftbukkit.block.CraftBiome;
 import org.bukkit.craftbukkit.block.CraftBlockType;
@@ -146,6 +152,8 @@ public final class PaperRegistries {
             start(Registries.PIG_SOUND_VARIANT, RegistryKey.PIG_SOUND_VARIANT).craft(Pig.SoundVariant.class, CraftPig.CraftSoundVariant::new).build(),
             start(Registries.ZOMBIE_NAUTILUS_VARIANT, RegistryKey.ZOMBIE_NAUTILUS_VARIANT).craft(ZombieNautilus.Variant.class, CraftZombieNautilus.CraftVariant::new).writable(PaperZombieNautilusVariantRegistryEntry.PaperBuilder::new),
             start(Registries.DIALOG, RegistryKey.DIALOG).craft(Dialog.class, PaperDialog::new, true).writable(PaperDialogRegistryEntry.PaperBuilder::new),
+            start(Registries.WORLD_CLOCK, RegistryKey.WORLD_CLOCK).craft(WorldClock.class, CraftWorldClock::new).writable(PaperWorldClockRegistryEntry.PaperBuilder::new).delayed(),
+            start(Registries.TIMELINE, RegistryKey.TIMELINE).craft(Timeline.class, CraftTimeline::new).writable(PaperTimelineRegistryEntry.PaperBuilder::new).delayed(),
 
             // api-only
             start(Registries.ENTITY_TYPE, RegistryKey.ENTITY_TYPE).apiOnly(PaperSimpleRegistry::entityType),

paper-server/src/main/java/io/papermc/paper/registry/data/PaperTimelineRegistryEntry.java

@@ -0,0 +1,101 @@
+package io.papermc.paper.registry.data;
+
+import io.papermc.paper.adventure.PaperAdventure;
+import io.papermc.paper.registry.PaperRegistries;
+import io.papermc.paper.registry.PaperRegistryBuilder;
+import io.papermc.paper.registry.TypedKey;
+import io.papermc.paper.registry.data.util.Conversions;
+import io.papermc.paper.world.WorldClock;
+import java.util.LinkedHashMap;
+import java.util.Map;
+import java.util.OptionalInt;
+import net.kyori.adventure.key.Key;
+import net.minecraft.core.Holder;
+import net.minecraft.resources.ResourceKey;
+import net.minecraft.world.timeline.Timeline;
+import org.jetbrains.annotations.Range;
+import org.jspecify.annotations.Nullable;
+
+import static io.papermc.paper.registry.data.util.Checks.asArgument;
+import static io.papermc.paper.registry.data.util.Checks.asArgumentMin;
+import static io.papermc.paper.registry.data.util.Checks.asConfigured;
+
+public class PaperTimelineRegistryEntry implements TimelineRegistryEntry {
+
+    protected final Conversions conversions;
+    protected @Nullable Timeline internal;
+    protected @Nullable Holder<net.minecraft.world.clock.WorldClock> clock;
+    protected OptionalInt periodTicks = OptionalInt.empty();
+    protected final Map<Key, TimeMarker> timeMarkers = new LinkedHashMap<>();
+
+    public PaperTimelineRegistryEntry(final Conversions conversions, final @Nullable Timeline internal) {
+        this.conversions = conversions;
+        this.internal = internal;
+
+        if (internal == null) {
+            return;
+        }
+        this.clock = internal.clock();
+        internal.periodTicks().ifPresent(period -> this.periodTicks = OptionalInt.of(period));
+        internal.registerTimeMarkers((key, marker) -> this.timeMarkers.put(PaperAdventure.asAdventure(key.identifier()), new TimeMarker(marker.ticks(), marker.showInCommands())));
+    }
+
+    @Override
+    public TypedKey<WorldClock> clock() {
+        return PaperRegistries.fromNms(asConfigured(this.clock, "clock").unwrapKey().orElseThrow());
+    }
+
+    @Override
+    public OptionalInt periodTicks() {
+        return this.periodTicks;
+    }
+
+    @Override
+    public Map<Key, TimeMarker> timeMarkers() {
+        return Map.copyOf(this.timeMarkers);
+    }
+
+    public static final class PaperBuilder extends PaperTimelineRegistryEntry implements TimelineRegistryEntry.Builder, PaperRegistryBuilder<Timeline, io.papermc.paper.world.Timeline> {
+
+        public PaperBuilder(final Conversions conversions, final @Nullable Timeline internal) {
+            super(conversions, internal);
+        }
+
+        @Override
+        public Builder clock(final TypedKey<WorldClock> clock) {
+            this.clock = this.conversions.getReferenceHolder(PaperRegistries.toNms(asArgument(clock, "clock")));
+            return this;
+        }
+
+        @Override
+        public Builder periodTicks(final @Range(from = 1, to = Integer.MAX_VALUE) int periodTicks) {
+            this.periodTicks = OptionalInt.of(asArgumentMin(periodTicks, "periodTicks", 1));
+            return this;
+        }
+
+        @Override
+        public Builder clearPeriodTicks() {
+            this.periodTicks = OptionalInt.empty();
+            return this;
+        }
+
+        @Override
+        public Builder addTimeMarker(final Key key, final @Range(from = 0, to = Integer.MAX_VALUE) int ticks, final boolean showInCommands) {
+            this.timeMarkers.put(asArgument(key, "key"), new TimeMarker(asArgumentMin(ticks, "ticks", 0), showInCommands));
+            return this;
+        }
+
+        @Override
+        public Timeline build() {
+            final Timeline.Builder builder = Timeline.builder(asConfigured(this.clock, "clock"));
+            if (this.periodTicks.isPresent()) {
+                builder.setPeriodTicks(this.periodTicks.getAsInt());
+            }
+            if (this.internal != null) {
+                builder.addTracks(this.internal.tracks);
+            }
+            this.timeMarkers.forEach((key, marker) -> builder.addTimeMarker(ResourceKey.create(net.minecraft.world.clock.ClockTimeMarkers.ROOT_ID, PaperAdventure.asVanilla(key)), marker.ticks(), marker.showInCommands()));
+            return builder.build();
+        }
+    }
+}

paper-server/src/main/java/io/papermc/paper/registry/data/PaperWorldClockRegistryEntry.java

@@ -0,0 +1,24 @@
+package io.papermc.paper.registry.data;
+
+import io.papermc.paper.registry.PaperRegistryBuilder;
+import io.papermc.paper.registry.data.util.Conversions;
+import net.minecraft.world.clock.WorldClock;
+import org.jspecify.annotations.Nullable;
+
+public class PaperWorldClockRegistryEntry implements WorldClockRegistryEntry {
+
+    public PaperWorldClockRegistryEntry(final Conversions ignoredConversions, final @Nullable WorldClock ignoredInternal) {
+    }
+
+    public static final class PaperBuilder extends PaperWorldClockRegistryEntry implements WorldClockRegistryEntry.Builder, PaperRegistryBuilder<WorldClock, io.papermc.paper.world.WorldClock> {
+
+        public PaperBuilder(final Conversions conversions, final @Nullable WorldClock internal) {
+            super(conversions, internal);
+        }
+
+        @Override
+        public WorldClock build() {
+            return new WorldClock();
+        }
+    }
+}

paper-server/src/main/java/io/papermc/paper/world/saveddata/PaperLevelOverrides.java

@@ -3,11 +3,14 @@ package io.papermc.paper.world.saveddata;
 import com.mojang.serialization.Codec;
 import com.mojang.serialization.Dynamic;
 import com.mojang.serialization.codecs.RecordCodecBuilder;
+import java.util.Optional;
 import net.minecraft.core.BlockPos;
+import net.minecraft.core.registries.Registries;
 import net.minecraft.resources.Identifier;
 import net.minecraft.resources.ResourceKey;
 import net.minecraft.util.Mth;
 import net.minecraft.util.datafix.DataFixTypes;
+import net.minecraft.world.clock.WorldClock;
 import net.minecraft.world.Difficulty;
 import net.minecraft.world.level.GameType;
 import net.minecraft.world.level.Level;
@@ -28,7 +31,8 @@ public final class PaperLevelOverrides extends SavedData implements ServerLevelD
         Codec.LONG.fieldOf("game_time").forGetter(levelOverrides -> levelOverrides.gameTime),
         Codec.BOOL.fieldOf("initialized").forGetter(levelOverrides -> levelOverrides.initialized),
         LEGACY_GAME_TYPE_CODEC.fieldOf("game_type").forGetter(levelOverrides -> levelOverrides.gameType),
-        LevelSettings.DifficultySettings.CODEC.fieldOf("difficulty_settings").forGetter(levelOverrides -> levelOverrides.difficultySettings)
+        LevelSettings.DifficultySettings.CODEC.fieldOf("difficulty_settings").forGetter(levelOverrides -> levelOverrides.difficultySettings),
+        ResourceKey.codec(Registries.WORLD_CLOCK).optionalFieldOf("clock").forGetter(levelOverrides -> levelOverrides.clock)
     ).apply(instance, PaperLevelOverrides::new));
     public static final SavedDataType<PaperLevelOverrides> TYPE = new SavedDataType<>(
         Identifier.fromNamespaceAndPath(Identifier.PAPER_NAMESPACE, "level_overrides"),
@@ -42,11 +46,12 @@ public final class PaperLevelOverrides extends SavedData implements ServerLevelD
     private boolean initialized;
     private GameType gameType;
     private LevelSettings.DifficultySettings difficultySettings;
+    private Optional<ResourceKey<WorldClock>> clock;
     private transient @Nullable PrimaryLevelData rootData;
     private transient ResourceKey<Level> dimension = Level.OVERWORLD;
 
     private PaperLevelOverrides() {
-        this(RespawnData.DEFAULT, 0L, false, GameType.SURVIVAL, LevelSettings.DifficultySettings.DEFAULT);
+        this(RespawnData.DEFAULT, 0L, false, GameType.SURVIVAL, LevelSettings.DifficultySettings.DEFAULT, Optional.empty());
     }
 
     private PaperLevelOverrides(
@@ -54,13 +59,15 @@ public final class PaperLevelOverrides extends SavedData implements ServerLevelD
         final long gameTime,
         final boolean initialized,
         final GameType gameType,
-        final LevelSettings.DifficultySettings difficultySettings
+        final LevelSettings.DifficultySettings difficultySettings,
+        final Optional<ResourceKey<WorldClock>> clock
     ) {
         this.respawnData = respawnData.normalized();
         this.gameTime = gameTime;
         this.initialized = initialized;
         this.gameType = gameType;
         this.difficultySettings = difficultySettings;
+        this.clock = clock;
     }
 
     public static PaperLevelOverrides createFromLiveLevelData(final PrimaryLevelData rootData) {
@@ -69,7 +76,8 @@ public final class PaperLevelOverrides extends SavedData implements ServerLevelD
             rootData.getGameTime(),
             false,
             rootData.getGameType(),
-            new LevelSettings.DifficultySettings(rootData.getDifficulty(), rootData.isHardcore(), rootData.isDifficultyLocked())
+            new LevelSettings.DifficultySettings(rootData.getDifficulty(), rootData.isHardcore(), rootData.isDifficultyLocked()),
+            Optional.empty()
         );
     }
 
@@ -82,7 +90,8 @@ public final class PaperLevelOverrides extends SavedData implements ServerLevelD
             levelData.get("Time").asLong(0L),
             levelData.get("initialized").asBoolean(true),
             GameType.byId(levelData.get("GameType").asInt(GameType.SURVIVAL.getId())),
-            levelData.get("difficulty_settings").read(LevelSettings.DifficultySettings.CODEC).result().orElse(LevelSettings.DifficultySettings.DEFAULT)
+            levelData.get("difficulty_settings").read(LevelSettings.DifficultySettings.CODEC).result().orElse(LevelSettings.DifficultySettings.DEFAULT),
+            Optional.empty()
         );
     }
 
@@ -113,6 +122,18 @@ public final class PaperLevelOverrides extends SavedData implements ServerLevelD
         }
     }
 
+    public Optional<ResourceKey<WorldClock>> clock() {
+        return this.clock;
+    }
+
+    public void setClock(final @Nullable ResourceKey<WorldClock> clock) {
+        final Optional<ResourceKey<WorldClock>> newClock = Optional.ofNullable(clock);
+        if (!this.clock.equals(newClock)) {
+            this.clock = newClock;
+            this.setDirty();
+        }
+    }
+
     public void setDifficultyLocked(final boolean difficultyLocked) {
         if (this.difficultySettings.locked() != difficultyLocked) {
             this.setDifficultySettings(new LevelSettings.DifficultySettings(this.difficultySettings.difficulty(), this.difficultySettings.hardcore(), difficultyLocked));

paper-server/src/main/java/org/bukkit/craftbukkit/CraftServer.java

@@ -13,7 +13,9 @@ import com.mojang.brigadier.exceptions.CommandSyntaxException;
 import io.papermc.paper.configuration.GlobalConfiguration;
 import io.papermc.paper.configuration.PaperServerConfiguration;
 import io.papermc.paper.configuration.ServerConfiguration;
+import io.papermc.paper.registry.PaperRegistries;
 import io.papermc.paper.world.PaperWorldLoader;
+import io.papermc.paper.world.WorldClock;
 import io.papermc.paper.world.migration.WorldFolderMigration;
 import io.papermc.paper.world.saveddata.PaperLevelOverrides;
 import it.unimi.dsi.fastutil.objects.Object2IntOpenHashMap;
@@ -45,6 +47,7 @@ import java.util.logging.Level;
 import java.util.logging.Logger;
 import java.util.stream.Collectors;
 import javax.imageio.ImageIO;
+import net.minecraft.SharedConstants;
 import net.md_5.bungee.api.chat.BaseComponent;
 import net.minecraft.Optionull;
 import net.minecraft.advancements.AdvancementHolder;
@@ -52,6 +55,8 @@ import net.minecraft.commands.CommandSourceStack;
 import net.minecraft.commands.Commands;
 import net.minecraft.commands.arguments.EntityArgument;
 import net.minecraft.core.BlockPos;
+import net.minecraft.core.Holder;
+import net.minecraft.core.HolderSet;
 import net.minecraft.core.RegistryAccess;
 import net.minecraft.core.registries.BuiltInRegistries;
 import net.minecraft.core.registries.Registries;
@@ -99,6 +104,7 @@ import net.minecraft.world.level.CustomSpawner;
 import net.minecraft.world.level.GameType;
 import net.minecraft.world.level.biome.BiomeManager;
 import net.minecraft.world.level.block.Block;
+import net.minecraft.world.level.dimension.DimensionType;
 import net.minecraft.world.level.dimension.LevelStem;
 import net.minecraft.world.level.levelgen.PatrolSpawner;
 import net.minecraft.world.level.levelgen.PhantomSpawner;
@@ -211,6 +217,7 @@ import org.bukkit.entity.SpawnCategory;
 import org.bukkit.event.inventory.InventoryType;
 import org.bukkit.event.server.BroadcastMessageEvent;
 import org.bukkit.event.server.ServerLoadEvent;
+import org.bukkit.event.world.ClockTimeSkipEvent;
 import org.bukkit.event.world.WorldUnloadEvent;
 import org.bukkit.generator.BiomeProvider;
 import org.bukkit.generator.ChunkGenerator;
@@ -908,6 +915,58 @@ public final class CraftServer implements Server {
         return new ArrayList<World>(this.worlds.values());
     }
 
+    @Override
+    public long getTime(final WorldClock clock) {
+        long time = this.getFullTime(clock) % SharedConstants.TICKS_PER_GAME_DAY;
+        if (time < 0) time += SharedConstants.TICKS_PER_GAME_DAY;
+        return time;
+    }
+
+    @Override
+    public void setTime(final WorldClock clock, final long time) {
+        long margin = (time - this.getFullTime(clock)) % SharedConstants.TICKS_PER_GAME_DAY;
+        if (margin < 0) margin += SharedConstants.TICKS_PER_GAME_DAY;
+        this.setFullTime(clock, this.getFullTime(clock) + margin);
+    }
+
+    @Override
+    public long getFullTime(final WorldClock clock) {
+        return this.console.clockManager().getTotalTicks(CraftWorldClock.bukkitToMinecraftHolder(clock));
+    }
+
+    @Override
+    public void setFullTime(final WorldClock clock, final long time) {
+        final Holder<net.minecraft.world.clock.WorldClock> nmsClock = CraftWorldClock.bukkitToMinecraftHolder(clock);
+        final long currentClockTime = this.console.clockManager().getTotalTicks(nmsClock);
+        final ClockTimeSkipEvent event = new ClockTimeSkipEvent(clock, ClockTimeSkipEvent.SkipReason.CUSTOM, time - currentClockTime);
+        this.getPluginManager().callEvent(event);
+        if (event.isCancelled()) {
+            return;
+        }
+
+        this.console.clockManager().setTotalTicks(nmsClock, currentClockTime + event.getSkipAmount());
+    }
+
+    @Override
+    public boolean isClockPaused(final WorldClock clock) {
+        return this.console.clockManager().isPaused(CraftWorldClock.bukkitToMinecraftHolder(clock));
+    }
+
+    @Override
+    public void setClockPaused(final WorldClock clock, final boolean paused) {
+        this.console.clockManager().setPaused(CraftWorldClock.bukkitToMinecraftHolder(clock), paused);
+    }
+
+    @Override
+    public float getClockRate(final WorldClock clock) {
+        return this.console.clockManager().rate(CraftWorldClock.bukkitToMinecraftHolder(clock));
+    }
+
+    @Override
+    public void setClockRate(final WorldClock clock, final float rate) {
+        this.console.clockManager().setRate(CraftWorldClock.bukkitToMinecraftHolder(clock), rate);
+    }
+
     @Override
     public boolean isTickingWorlds() {
         return console.isIteratingOverLevels;
@@ -1267,6 +1326,17 @@ public final class CraftServer implements Server {
         if (customStem == null) {
             throw new IllegalStateException("Missing level stem for world " + name + " using key " + actualDimension);
         }
+        boolean dimensionTypeChanged = false;
+        if (creator.timelines() != null) {
+            customStem = this.createLevelStemWithClockAndTimelines(customStem, creator, this.console.registryAccess());
+            dimensionTypeChanged = true;
+        }
+        WorldGenSettings savedWorldGenSettings = genSettingsFinal;
+        if (dimensionTypeChanged) {
+            final Map<ResourceKey<LevelStem>, LevelStem> dimensions = new LinkedHashMap<>(genSettingsFinal.dimensions().dimensions());
+            dimensions.put(actualDimension, customStem);
+            savedWorldGenSettings = new WorldGenSettings(genSettingsFinal.options(), new WorldDimensions(dimensions));
+        }
 
         WorldInfo worldInfo = new CraftWorldInfo(loadedWorldData.bukkitName(), CraftNamespacedKey.fromMinecraft(dimensionKey.identifier()), genSettingsFinal.options().seed(), primaryLevelData.enabledFeatures(), creator.environment(), customStem.type().value(), customStem.generator(), this.getHandle().getServer().registryAccess(), loadedWorldData.uuid());
         if (biomeProvider == null && chunkGenerator != null) {
@@ -1274,7 +1344,8 @@ public final class CraftServer implements Server {
         }
 
         final SavedDataStorage savedDataStorage = new SavedDataStorage(this.console.storageSource.getDimensionPath(dimensionKey).resolve(LevelResource.DATA.id()), this.console.getFixerUpper(), this.console.registryAccess());
-        savedDataStorage.set(WorldGenSettings.TYPE, new WorldGenSettings(genSettingsFinal.options(), genSettingsFinal.dimensions()));
+        loadedWorldData.levelOverrides().setClock(creator.clock() == null ? null : PaperRegistries.toNms(creator.clock()));
+        savedDataStorage.set(WorldGenSettings.TYPE, savedWorldGenSettings);
         List<CustomSpawner> list = ImmutableList.of(
             new PhantomSpawner(), new PatrolSpawner(), new CatSpawner(), new VillageSiege(), new WanderingTraderSpawner(savedDataStorage)
         );
@@ -1312,6 +1383,33 @@ public final class CraftServer implements Server {
         return serverLevel.getWorld();
     }
 
+    private LevelStem createLevelStemWithClockAndTimelines(final LevelStem stem, final WorldCreator creator, final RegistryAccess registryAccess) {
+        final DimensionType type = stem.type().value();
+        final List<io.papermc.paper.registry.TypedKey<io.papermc.paper.world.Timeline>> timelineKeys = creator.timelines();
+        final HolderSet<net.minecraft.world.timeline.Timeline> timelines = timelineKeys == null
+            ? type.timelines()
+            : HolderSet.direct(timelineKeys.stream().map(key -> registryAccess.lookupOrThrow(Registries.TIMELINE).getOrThrow(PaperRegistries.toNms(key))).toList());
+        final DimensionType newType = new DimensionType(
+            type.hasFixedTime(),
+            type.hasSkyLight(),
+            type.hasCeiling(),
+            type.hasEnderDragonFight(),
+            type.coordinateScale(),
+            type.minY(),
+            type.height(),
+            type.logicalHeight(),
+            type.infiniburn(),
+            type.ambientLight(),
+            type.monsterSettings(),
+            type.skybox(),
+            type.cardinalLightType(),
+            type.attributes(),
+            timelines,
+            type.defaultClock()
+        );
+        return new LevelStem(Holder.direct(newType), stem.generator());
+    }
+
     @Override
     public boolean unloadWorld(String name, boolean save) {
         return this.unloadWorld(this.getWorld(name), save);

paper-server/src/main/java/org/bukkit/craftbukkit/CraftTimeline.java

@@ -0,0 +1,21 @@
+package org.bukkit.craftbukkit;
+
+import io.papermc.paper.registry.HolderableBase;
+import io.papermc.paper.world.Timeline;
+import net.minecraft.core.Holder;
+import net.minecraft.core.registries.Registries;
+
+public class CraftTimeline extends HolderableBase<net.minecraft.world.timeline.Timeline> implements Timeline {
+
+    public static Timeline minecraftHolderToBukkit(final Holder<net.minecraft.world.timeline.Timeline> minecraft) {
+        return CraftRegistry.minecraftHolderToBukkit(minecraft, Registries.TIMELINE);
+    }
+
+    public static Holder<net.minecraft.world.timeline.Timeline> bukkitToMinecraftHolder(final Timeline bukkit) {
+        return CraftRegistry.bukkitToMinecraftHolder(bukkit);
+    }
+
+    public CraftTimeline(final Holder<net.minecraft.world.timeline.Timeline> holder) {
+        super(holder);
+    }
+}

paper-server/src/main/java/org/bukkit/craftbukkit/CraftWorld.java

@@ -13,6 +13,8 @@ import io.papermc.paper.raytracing.PositionedRayTraceConfigurationBuilderImpl;
 import io.papermc.paper.raytracing.RayTraceTarget;
 import io.papermc.paper.registry.RegistryAccess;
 import io.papermc.paper.registry.RegistryKey;
+import io.papermc.paper.world.Timeline;
+import io.papermc.paper.world.WorldClock;
 import it.unimi.dsi.fastutil.objects.Object2IntOpenHashMap;
 import java.nio.file.Path;
 import java.util.ArrayList;
@@ -139,8 +141,6 @@ import org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason;
 import org.bukkit.event.weather.LightningStrikeEvent;
 import org.bukkit.event.weather.ThunderChangeEvent;
 import org.bukkit.event.weather.WeatherChangeEvent;
-import org.bukkit.event.world.SpawnChangeEvent;
-import org.bukkit.event.world.TimeSkipEvent;
 import org.bukkit.generator.BiomeProvider;
 import org.bukkit.generator.BlockPopulator;
 import org.bukkit.generator.ChunkGenerator;
@@ -793,24 +793,31 @@ public class CraftWorld extends CraftRegionAccessor implements World {
 
     @Override
     public long getFullTime() {
-        return this.world.getDefaultClockTime();
+        final WorldClock clock = this.getClock();
+        return clock == null ? 0L : this.server.getFullTime(clock);
     }
 
     @Override
     public void setFullTime(long time) {
-        if (this.world.dimensionType().defaultClock().isEmpty()) {
+        this.server.setFullTime(this.requireDefaultClock(), time);
+    }
+
+    @Override
+    public WorldClock getClock() {
+        return this.world.getClock().map(CraftWorldClock::minecraftHolderToBukkit).orElse(null);
+    }
+
+    @Override
+    public List<Timeline> getTimelines() {
+        return this.world.dimensionType().timelines().stream().map(CraftTimeline::minecraftHolderToBukkit).toList();
+    }
+
+    private WorldClock requireDefaultClock() {
+        final WorldClock clock = this.getClock();
+        if (clock == null) {
             throw new IllegalArgumentException("Cannot set time in world without world clock");
         }
-
-        final long currentClockTime = this.world.getDefaultClockTime();
-        final TimeSkipEvent event = new TimeSkipEvent(this, TimeSkipEvent.SkipReason.CUSTOM, time - currentClockTime);
-        this.server.getPluginManager().callEvent(event);
-        if (event.isCancelled()) {
-            return;
-        }
-
-        // Updates the clock for all players
-        this.world.clockManager().setTotalTicks(this.world.dimensionType().defaultClock().get(), currentClockTime + event.getSkipAmount());
+        return clock;
     }
 
     // Paper start

paper-server/src/main/java/org/bukkit/craftbukkit/CraftWorldClock.java

@@ -0,0 +1,21 @@
+package org.bukkit.craftbukkit;
+
+import io.papermc.paper.registry.HolderableBase;
+import io.papermc.paper.world.WorldClock;
+import net.minecraft.core.Holder;
+import net.minecraft.core.registries.Registries;
+
+public class CraftWorldClock extends HolderableBase<net.minecraft.world.clock.WorldClock> implements WorldClock {
+
+    public static WorldClock minecraftHolderToBukkit(final Holder<net.minecraft.world.clock.WorldClock> minecraft) {
+        return CraftRegistry.minecraftHolderToBukkit(minecraft, Registries.WORLD_CLOCK);
+    }
+
+    public static Holder<net.minecraft.world.clock.WorldClock> bukkitToMinecraftHolder(final WorldClock bukkit) {
+        return CraftRegistry.bukkitToMinecraftHolder(bukkit);
+    }
+
+    public CraftWorldClock(final Holder<net.minecraft.world.clock.WorldClock> holder) {
+        super(holder);
+    }
+}

paper-server/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java

@@ -1537,13 +1537,14 @@ public class CraftPlayer extends CraftHumanEntity implements Player, PluginMessa
         this.getHandle().relativeTime = tickTime;
 
         final ServerLevel level = this.getHandle().level();
-        if (this.getHandle().connection == null || level.dimensionType().defaultClock().isEmpty()) {
+        final java.util.Optional<Holder<WorldClock>> clock = level.getClock();
+        if (this.getHandle().connection == null || clock.isEmpty()) {
             return;
         }
 
         final long gameTime = level.getGameTime();
         final long playerClockTime = this.getHandle().getPlayerTime();
-        final Holder<WorldClock> worldClock = level.dimensionType().defaultClock().get();
+        final Holder<WorldClock> worldClock = clock.get();
         final boolean paused = !this.getHandle().relativeTime || !level.getGameRules().get(GameRules.ADVANCE_TIME) || level.clockManager().isPaused(worldClock);
         final ClockNetworkState clockState = new ClockNetworkState(
             playerClockTime,

paper-server/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java

@@ -261,6 +261,7 @@ import org.bukkit.event.raid.RaidStopEvent;
 import org.bukkit.event.raid.RaidTriggerEvent;
 import org.bukkit.event.vehicle.VehicleCreateEvent;
 import org.bukkit.event.weather.LightningStrikeEvent;
+import org.bukkit.event.world.ClockTimeSkipEvent;
 import org.bukkit.event.world.EntitiesLoadEvent;
 import org.bukkit.event.world.EntitiesUnloadEvent;
 import org.bukkit.event.world.LootGenerateEvent;
@@ -2417,4 +2418,9 @@ public class CraftEventFactory {
         }
         return true;
     }
+
+    public static ClockTimeSkipEvent callTimeSkipEvent(final net.minecraft.core.Holder<net.minecraft.world.clock.WorldClock> clock, final long skipAmount) {
+        final io.papermc.paper.world.WorldClock bukkitClock = org.bukkit.craftbukkit.CraftWorldClock.minecraftHolderToBukkit(clock);
+        return new ClockTimeSkipEvent(bukkitClock, ClockTimeSkipEvent.SkipReason.COMMAND, skipAmount);
+    }
 }