5.9.0 Release

Remove rewriter overrides in AbstractProtocol (#4913 )
Fix profile with multiple properties of the same key in 1.20.5->1.20.3 (#4909 )
2026-11-04 08:52:10 -05:00 · 2026-04-19 15:36:05 +02:00 · 2026-04-19 08:30:13 +02:00 · 2026-04-17 22:33:28 +02:00 · 2026-04-17 14:44:57 +02:00 · 2026-04-15 20:31:15 +02:00
270 changed files with 5741 additions and 2420 deletions
@@ -15,7 +15,7 @@ jobs:
      with:
        persist-credentials: false
    - name: Set up Gradle
-      uses: gradle/actions/setup-gradle@f29f5a9d7b09a7c6b29859002d29d24e1674c884 # 5.0.1
+      uses: gradle/actions/setup-gradle@39e147cb9de83bb9910b8ef8bd7fff0ee20fcd6f # 6.0.1
    - name: Set up JDK 17
      uses: actions/setup-java@be666c2fcd27ec809703dec50e508c2fdc7f6654 # 5.2.0
      with:
@@ -27,7 +27,7 @@ jobs:
    - name: Upload Artifacts to GitHub
      # Only upload on the preview repository as there is no CI job for it.
      if: ${{ github.repository == 'ViaVersion/ViaVersionDev' && github.ref_name == 'preview' }}
-      uses: actions/upload-artifact@b7c566a772e6b6bfb58ed0dc250532a479d7789f # 6.0.0
+      uses: actions/upload-artifact@bbbca2ddaa5d8feaa63e36b76fdaad77386f024f # 7.0.0
      with:
        name: Artifacts
        path: build/libs/
@@ -20,7 +20,7 @@ jobs:
        with:
          persist-credentials: false
      - name: Set up Gradle
-        uses: gradle/actions/setup-gradle@f29f5a9d7b09a7c6b29859002d29d24e1674c884 # 5.0.1
+        uses: gradle/actions/setup-gradle@39e147cb9de83bb9910b8ef8bd7fff0ee20fcd6f # 6.0.1
      - name: Set up JDK 17
        uses: actions/setup-java@be666c2fcd27ec809703dec50e508c2fdc7f6654 # 5.2.0
        with:
@@ -19,6 +19,8 @@ classes/
 *.ipr
 *.iws

+benchmark/
+
 # VSCode

 .settings/
@@ -7,11 +7,15 @@
 **Allows the connection of higher client versions to lower server versions -
 it works on any platform you can think of.**

-The base ViaVersion jar runs on Paper and Velocity. We also have projects integrating ViaVersion to run
-on Fabric, Forge, Sponge, or as a standalone proxy to join from basically any client version on
-any server version from the past decade. **See [HERE](https://viaversion.com) for an overview of the different Via\* projects.**
+The base ViaVersion jar runs on [Paper](https://papermc.io/software/paper/)
+and [Velocity](https://papermc.io/software/velocity/). We also have projects integrating ViaVersion to run
+on [Fabric](https://github.com/ViaVersion/ViaFabric), [Forge](https://github.com/ViaVersion/ViaForge), [Bungee](https://github.com/ViaVersion/ViaBungee), [Sponge](https://github.com/ViaVersion/ViaSponge),
+or as [a standalone proxy](https://github.com/ViaVersion/ViaProxy) to join from basically any client version on
+any server version from the past decade. **See [HERE](https://viaversion.com) for an overview of the different Via\*
+projects.**

-Note that ViaVersion will be able to **run best on either Paper servers or through [ViaFabricPlus](https://github.com/ViaVersion/ViaFabricPlus?tab=readme-ov-file#viafabricplus)** due to having
+Note that ViaVersion will be able to **run best on either Paper servers or
+through [ViaFabricPlus](https://github.com/ViaVersion/ViaFabricPlus?tab=readme-ov-file#viafabricplus)** due to having
 direct access to client/server state and more extensive API.

 Supported Versions:
@@ -22,10 +26,16 @@ Supported Versions:

 Snapshot support
 --------
-**ViaVersion will only be released a few days *after* a Minecraft update** unless the protocol changes of the update were trivial. If you want early-access, usually days or even weeks before the final release, you can subscribe to either:
- [GitHub Sponsors](https://github.com/sponsors/kennytv/sponsorships?sponsor=kennytv&tier_id=385613&preview=false) (preferred option. Use the `/verify` command on this Discord after), or alternatively
- [Patreon](https://www.patreon.com/kennytv/membership) (see the highest tier and make sure to link Patreon to your Discord account under Settings->Connections)
-  This also includes access to a private repository with the code, which will be pushed to the public repository after the given delay on a Minecraft update.
+**ViaVersion will only be released a few days *after* a Minecraft update** unless the protocol changes of the update
+were trivial. If you want early-access, usually days or even weeks before the final release, you can subscribe to
+either:
+
+- [GitHub Sponsors](https://github.com/sponsors/kennytv/sponsorships?sponsor=kennytv&tier_id=385613&preview=false) (
+  preferred option. Use the `/verify` command on this Discord after), or alternatively
+- [Patreon](https://www.patreon.com/kennytv/membership) (see the highest tier and make sure to link Patreon to your
+  Discord account under Settings->Connections)
+  This also includes access to a private repository with the code, which will be pushed to the public repository after
+  the given delay on a Minecraft update.

 Releases/Dev Builds
 --------
@@ -89,7 +99,8 @@ You need JDK 17 or newer to build ViaVersion.

 Mapping Files
 --------------
-Mapping files are generated and managed in our [Mappings repository](https://github.com/ViaVersion/Mappings). The generated mapping output is stored [here](./common/src/main/resources/assets/viaversion).
+Mapping files are generated and managed in our [Mappings repository](https://github.com/ViaVersion/Mappings). The
+generated mapping output is stored [here](./common/src/main/resources/assets/viaversion).

 Resources
 --------
@@ -1,6 +1,6 @@
 /*
 * This file is part of ViaVersion - https://github.com/ViaVersion/ViaVersion
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * Copyright (C) 2016-2026 ViaVersion and contributors
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
@@ -37,6 +37,7 @@ public interface ViaVersionCommand {
    /**
     * Removes a subcommand by name, can be used to unload default subcommands which are not supported
     * on the platform.
+     *
     * @param name Subcommand name
     */
    void removeSubCommand(String name);
@@ -0,0 +1,123 @@
+/*
+ * This file is part of ViaVersion - https://github.com/ViaVersion/ViaVersion
+ * Copyright (C) 2016-2026 ViaVersion and contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+package com.viaversion.viaversion.api.data;
+
+import com.google.common.base.Preconditions;
+import com.viaversion.viaversion.api.data.MappingDataLoader.IdentifiersPair;
+import com.viaversion.viaversion.util.Key;
+import it.unimi.dsi.fastutil.objects.Object2IntMap;
+import org.checkerframework.checker.nullness.qual.Nullable;
+
+public class FullIdentityMappings implements FullMappings {
+    private static final String[] EMPTY_ARRAY = new String[0];
+    private final Object2IntMap<String> stringToId;
+    private final String[] idToString;
+    private final Mappings mappings;
+
+    public FullIdentityMappings(final IdentifiersPair identifiersPair, final Mappings mappings) {
+        Preconditions.checkNotNull(mappings, "Mappings cannot be null");
+        this.mappings = mappings;
+        this.stringToId = FullMappingsBase.toInverseMap(identifiersPair.unmapped());
+        this.idToString = identifiersPair.unmapped().toArray(EMPTY_ARRAY);
+    }
+
+    private FullIdentityMappings(final Object2IntMap<String> stringToId, final String[] idToString, final Mappings mappings) {
+        this.stringToId = stringToId;
+        this.idToString = idToString;
+        this.mappings = mappings;
+    }
+
+    @Override
+    public int id(final String identifier) {
+        return stringToId.getInt(Key.stripMinecraftNamespace(identifier));
+    }
+
+    @Override
+    public int mappedId(final String mappedIdentifier) {
+        return id(mappedIdentifier);
+    }
+
+    @Override
+    public String identifier(final int id) {
+        if (id < 0 || id >= idToString.length) {
+            return null;
+        }
+        final String identifier = idToString[id];
+        return Key.namespaced(identifier);
+    }
+
+    @Override
+    public @Nullable String identifier(final String mappedIdentifier) {
+        final int mappedId = mappedId(mappedIdentifier);
+        if (mappedId == -1) {
+            return null;
+        }
+        final int id = mappings.inverse().getNewId(mappedId);
+        return id != -1 ? identifier(id) : null;
+    }
+
+    @Override
+    public @Nullable String mappedIdentifier(final int mappedId) {
+        return identifier(mappedId);
+    }
+
+    @Override
+    public @Nullable String mappedIdentifier(final String identifier) {
+        return identifier(identifier);
+    }
+
+    @Override
+    public int getNewId(int id) {
+        return mappings.getNewId(id);
+    }
+
+    @Override
+    public void setNewId(int id, int mappedId) {
+        mappings.setNewId(id, mappedId);
+    }
+
+    @Override
+    public int size() {
+        return mappings.size();
+    }
+
+    @Override
+    public int mappedSize() {
+        return mappings.mappedSize();
+    }
+
+    @Override
+    public boolean isIdentity() {
+        return true;
+    }
+
+    @Override
+    public boolean isIntIdIdentity() {
+        return true;
+    }
+
+    @Override
+    public FullMappings inverse() {
+        return new FullIdentityMappings(stringToId, idToString, mappings.inverse());
+    }
+}
@@ -77,6 +77,14 @@ public interface FullMappings extends BiMappings {
     */
    @Nullable String mappedIdentifier(String identifier);

+    /**
+     * Returns whether the int id mappings are identity mappings.
+     *
+     * @return whether the int id mappings are identity mappings
+     * @see #isIdentity()
+     */
+    boolean isIntIdIdentity();
+
    @Override
    FullMappings inverse();
 }
@@ -23,6 +23,7 @@
 package com.viaversion.viaversion.api.data;

 import com.google.common.base.Preconditions;
+import com.viaversion.viaversion.api.data.MappingDataLoader.IdentifiersPair;
 import com.viaversion.viaversion.util.Key;
 import it.unimi.dsi.fastutil.objects.Object2IntMap;
 import it.unimi.dsi.fastutil.objects.Object2IntOpenHashMap;
@@ -37,13 +38,13 @@ public class FullMappingsBase implements FullMappings {
    private final String[] mappedIdToString;
    private final Mappings mappings;

-    public FullMappingsBase(final List<String> unmappedIdentifiers, final List<String> mappedIdentifiers, final Mappings mappings) {
+    public FullMappingsBase(final IdentifiersPair identifiersPair, final Mappings mappings) {
        Preconditions.checkNotNull(mappings, "Mappings cannot be null");
        this.mappings = mappings;
-        this.stringToId = toInverseMap(unmappedIdentifiers);
-        this.mappedStringToId = toInverseMap(mappedIdentifiers);
-        this.idToString = unmappedIdentifiers.toArray(EMPTY_ARRAY);
-        this.mappedIdToString = mappedIdentifiers.toArray(EMPTY_ARRAY);
+        this.stringToId = toInverseMap(identifiersPair.unmapped());
+        this.idToString = identifiersPair.unmapped().toArray(EMPTY_ARRAY);
+        this.mappedStringToId = toInverseMap(identifiersPair.mapped());
+        this.mappedIdToString = identifiersPair.mapped().toArray(EMPTY_ARRAY);
    }

    private FullMappingsBase(final Object2IntMap<String> stringToId, final Object2IntMap<String> mappedStringToId, final String[] idToString, final String[] mappedIdToString, final Mappings mappings) {
@@ -54,7 +55,11 @@ public class FullMappingsBase implements FullMappings {
        this.mappings = mappings;
    }

-    private static Object2IntMap<String> toInverseMap(final List<String> list) {
+    public static FullMappings of(final IdentifiersPair identifiersPair, final Mappings mappings) {
+        return mappings.isIdentity() && identifiersPair.identity() ? new FullIdentityMappings(identifiersPair, mappings) : new FullMappingsBase(identifiersPair, mappings);
+    }
+
+    static Object2IntMap<String> toInverseMap(final List<String> list) {
        final Object2IntMap<String> map = new Object2IntOpenHashMap<>(list.size());
        map.defaultReturnValue(-1);
        for (int i = 0; i < list.size(); i++) {
@@ -135,6 +140,11 @@ public class FullMappingsBase implements FullMappings {
        return mappings.mappedSize();
    }

+    @Override
+    public boolean isIntIdIdentity() {
+        return mappings.isIdentity();
+    }
+
    @Override
    public FullMappings inverse() {
        return new FullMappingsBase(mappedStringToId, stringToId, mappedIdToString, idToString, mappings.inverse());
@@ -38,4 +38,9 @@ public record IdentityMappings(int size, int mappedSize) implements Mappings {
    public Mappings inverse() {
        return new IdentityMappings(mappedSize, size);
    }
+
+    @Override
+    public boolean isIdentity() {
+        return true;
+    }
 }
@@ -170,6 +170,8 @@ public interface MappingData {

    @Nullable FullMappings getRecipeSerializerMappings();

+    @Nullable FullMappings getSlotDisplayMappings();
+
    @Nullable FullMappings getDataComponentSerializerMappings();

    default @Nullable FullMappings getFullMappings(final MappingType mappingType) {
@@ -26,6 +26,7 @@ import com.viaversion.nbt.tag.CompoundTag;
 import com.viaversion.nbt.tag.IntArrayTag;
 import com.viaversion.nbt.tag.Tag;
 import com.viaversion.viaversion.api.Via;
+import com.viaversion.viaversion.api.data.MappingDataLoader.IdentifiersPair;
 import com.viaversion.viaversion.api.minecraft.RegistryType;
 import com.viaversion.viaversion.api.minecraft.TagData;
 import it.unimi.dsi.fastutil.ints.IntOpenHashSet;
@@ -45,6 +46,7 @@ public class MappingDataBase implements MappingData {
    protected FullMappings entityMappings;
    protected FullMappings recipeSerializerMappings;
    protected FullMappings itemDataSerializerMappings;
+    protected FullMappings slotDisplayMappings;
    protected FullMappings attributeMappings;
    protected FullMappings blockEntityMappings;
    protected ParticleMappings particleMappings;
@@ -89,19 +91,19 @@ public class MappingDataBase implements MappingData {

            entityMappings = loadFullMappings(data, unmappedIdentifierData, mappedIdentifierData, "entities");
            argumentTypeMappings = loadFullMappings(data, unmappedIdentifierData, mappedIdentifierData, "argumenttypes");
+            slotDisplayMappings = loadFullMappings(data, unmappedIdentifierData, mappedIdentifierData, "slot_displays");
            recipeSerializerMappings = loadFullMappings(data, unmappedIdentifierData, mappedIdentifierData, "recipe_serializers");
            itemDataSerializerMappings = loadFullMappings(data, unmappedIdentifierData, mappedIdentifierData, "data_component_type");
            attributeMappings = loadFullMappings(data, unmappedIdentifierData, mappedIdentifierData, "attributes");
            blockEntityMappings = loadFullMappings(data, unmappedIdentifierData, mappedIdentifierData, "blockentities");

-            final List<String> unmappedParticles = identifiersFromGlobalIds(unmappedIdentifierData, "particles");
-            final List<String> mappedParticles = identifiersFromGlobalIds(mappedIdentifierData, "particles");
-            if (unmappedParticles != null && mappedParticles != null) {
+            final IdentifiersPair particleIdentifiers = identifiersFromGlobalIds(unmappedIdentifierData, mappedIdentifierData, "particles");
+            if (particleIdentifiers != null) {
                Mappings particleMappings = loadMappings(data, "particles");
                if (particleMappings == null) {
-                    particleMappings = new IdentityMappings(unmappedParticles.size(), mappedParticles.size());
+                    particleMappings = new IdentityMappings(particleIdentifiers.unmapped().size(), particleIdentifiers.mapped().size());
                }
-                this.particleMappings = new ParticleMappings(unmappedParticles, mappedParticles, particleMappings);
+                this.particleMappings = new ParticleMappings(particleIdentifiers, particleMappings);
            }
        } else {
            // Might not have identifiers in older versions
@@ -130,6 +132,10 @@ public class MappingDataBase implements MappingData {
        return MappingDataLoader.INSTANCE.identifiersFromGlobalIds(mappingsTag, key);
    }

+    protected @Nullable IdentifiersPair identifiersFromGlobalIds(final CompoundTag unmappedTag, final CompoundTag mappedTag, final String key) {
+        return MappingDataLoader.INSTANCE.identifiersFromGlobalIds(unmappedTag, mappedTag, key);
+    }
+
    protected @Nullable CompoundTag readMappingsFile(final String name) {
        return MappingDataLoader.INSTANCE.loadNBT(name);
    }
@@ -156,14 +162,12 @@ public class MappingDataBase implements MappingData {
            return null;
        }

-        final List<String> unmappedIdentifiers = identifiersFromGlobalIds(unmappedIdentifiersTag, key);
-        final List<String> mappedIdentifiers = identifiersFromGlobalIds(mappedIdentifiersTag, key);
+        final IdentifiersPair identifiersPair = identifiersFromGlobalIds(unmappedIdentifiersTag, mappedIdentifiersTag, key);
        Mappings mappings = loadBiMappings(data, key); // Load as bi-mappings to keep the inverse cached
        if (mappings == null) {
-            mappings = new IdentityMappings(unmappedIdentifiers.size(), mappedIdentifiers.size());
+            mappings = new IdentityMappings(identifiersPair.unmapped().size(), identifiersPair.mapped().size());
        }
-
-        return new FullMappingsBase(unmappedIdentifiers, mappedIdentifiers, mappings);
+        return FullMappingsBase.of(identifiersPair, mappings);
    }

    protected @Nullable BiMappings loadBiMappings(final CompoundTag data, final String key) {
@@ -335,6 +339,11 @@ public class MappingDataBase implements MappingData {
        return recipeSerializerMappings;
    }

+    @Override
+    public @Nullable FullMappings getSlotDisplayMappings() {
+        return slotDisplayMappings;
+    }
+
    @Override
    public @Nullable IntSet changedBlocks() {
        return changedBlocks;
@@ -81,8 +81,9 @@ public class MappingDataLoader {
        for (final Map.Entry<String, Tag> entry : globalIdentifiers.entrySet()) {
            //noinspection unchecked
            final ListTag<StringTag> value = (ListTag<StringTag>) entry.getValue();
-            final String[] array = new String[value.size()];
-            for (int i = 0, size = value.size(); i < size; i++) {
+            final int size = value.size();
+            final String[] array = new String[size];
+            for (int i = 0; i < size; i++) {
                array[i] = value.get(i).getValue();
            }
            GLOBAL_IDENTIFIER_INDEXES.put(entry.getKey(), array);
@@ -272,13 +273,60 @@ public class MappingDataLoader {

    public @Nullable List<String> identifiersFromGlobalIds(final CompoundTag mappingsTag, final String key) {
        final Mappings mappings = loadMappings(mappingsTag, key);
-        if (mappings == null) {
+        return mappings != null ? identifiers(mappings, key) : null;
+
+    }
+
+    /**
+     * Returns a pair of identifier lists, also keeping track of whether the two lists are equal.
+     *
+     * @param unmappedTag unmapped mappings tag
+     * @param mappedTag   mapped mappings tag
+     * @param key         mappings key
+     * @return pair of identifier lists
+     */
+    public @Nullable IdentifiersPair identifiersFromGlobalIds(final CompoundTag unmappedTag, final CompoundTag mappedTag, final String key) {
+        final Mappings unmapped = loadMappings(unmappedTag, key);
+        if (unmapped == null) {
            return null;
        }

+        final Mappings mapped = loadMappings(mappedTag, key);
+        if (mapped == null) {
+            return null;
+        }
+
+        final int size = unmapped.size();
+        if (size != mapped.size()) {
+            return new IdentifiersPair(identifiers(unmapped, key), identifiers(mapped, key), false);
+        }
+
+        // Small optimization to only load one array and reduce loading for full mappings
+        final List<String> unmappedIdentifiers = new ArrayList<>(size);
+        final List<String> mappedIdentifiers = new ArrayList<>(size);
+        boolean identity = true;
+        for (int i = 0; i < size; i++) {
+            final int unmappedGlobalId = unmapped.getNewId(i);
+            final int mappedGlobalId = mapped.getNewId(i);
+            final String unmappedIdentifier = identifierFromGlobalId(key, unmappedGlobalId);
+            if (unmappedGlobalId == mappedGlobalId) {
+                unmappedIdentifiers.add(unmappedIdentifier);
+                mappedIdentifiers.add(unmappedIdentifier);
+                continue;
+            }
+
+            identity = false;
+            unmappedIdentifiers.add(unmappedIdentifier);
+            mappedIdentifiers.add(identifierFromGlobalId(key, mappedGlobalId));
+        }
+        return identity ? new IdentifiersPair(unmappedIdentifiers) : new IdentifiersPair(unmappedIdentifiers, mappedIdentifiers);
+    }
+
+    private List<String> identifiers(final Mappings mappings, final String key) {
        final List<String> identifiers = new ArrayList<>(mappings.size());
        for (int i = 0; i < mappings.size(); i++) {
-            identifiers.add(identifierFromGlobalId(key, mappings.getNewId(i)));
+            final int globalId = mappings.getNewId(i);
+            identifiers.add(identifierFromGlobalId(key, globalId));
        }
        return identifiers;
    }
@@ -342,4 +390,15 @@ public class MappingDataLoader {

        T create(V mappings, int mappedSize);
    }
+
+    public record IdentifiersPair(List<String> unmapped, List<String> mapped, boolean identity) {
+
+        public IdentifiersPair(final List<String> unmapped, final List<String> mapped) {
+            this(unmapped, mapped, false);
+        }
+
+        public IdentifiersPair(final List<String> identifiers) {
+            this(identifiers, identifiers, true);
+        }
+    }
 }
@@ -22,6 +22,8 @@
 */
 package com.viaversion.viaversion.api.data;

+import org.checkerframework.checker.nullness.qual.Nullable;
+
 public interface Mappings {

    /**
@@ -84,4 +86,40 @@ public interface Mappings {
     * @return mappings with keys and values swapped
     */
    Mappings inverse();
+
+
+    /**
+     * Returns whether the mappings are unchanged identity mappings.
+     *
+     * @return whether the mappings are unchanged identity mappings
+     */
+    default boolean isIdentity() {
+        return false;
+    }
+
+    /**
+     * Returns whether the mappings null or identity mappings.
+     *
+     * @param mappings mappings
+     * @return whether the mappings are identity mappings
+     * @see #isFullIdentity(Mappings)
+     */
+    static boolean isIntIdIdentity(@Nullable final Mappings mappings) {
+        if (mappings == null) {
+            return true;
+        }
+        return mappings instanceof FullMappings fullMappings ? fullMappings.isIntIdIdentity() : mappings.isIdentity();
+    }
+
+    /**
+     * Returns whether the mappings null or full identity mappings.
+     * Stronger than {@link #isIntIdIdentity(Mappings)}, but equal to that if not {@link FullMappings}.
+     *
+     * @param mappings mappings
+     * @return whether the mappings are full identity mappings
+     * @see #isIntIdIdentity(Mappings)
+     */
+    static boolean isFullIdentity(@Nullable final Mappings mappings) {
+        return mappings == null || mappings.isIdentity();
+    }
 }
@@ -22,16 +22,16 @@
 */
 package com.viaversion.viaversion.api.data;

+import com.viaversion.viaversion.api.data.MappingDataLoader.IdentifiersPair;
 import it.unimi.dsi.fastutil.ints.IntArrayList;
 import it.unimi.dsi.fastutil.ints.IntList;
-import java.util.List;

 public class ParticleMappings extends FullMappingsBase {
    private final IntList itemParticleIds = new IntArrayList(4);
    private final IntList blockParticleIds = new IntArrayList(4);

-    public ParticleMappings(final List<String> unmappedIdentifiers, final List<String> mappedIdentifiers, final Mappings mappings) {
-        super(unmappedIdentifiers, mappedIdentifiers, mappings);
+    public ParticleMappings(final IdentifiersPair identifiersPair, final Mappings mappings) {
+        super(identifiersPair, mappings);
        addBlockParticle("block");
        addBlockParticle("falling_dust");
        addBlockParticle("block_marker");
@@ -31,8 +31,8 @@ import org.checkerframework.checker.nullness.qual.Nullable;
 * Represents an animal variant (e.g. for cows, pigs, chickens).
 *
 * @param modelType model type id
- * @param texture texture path
- * @param biomes biomes this variant can spawn in, if limited to specific biomes
+ * @param texture   texture path
+ * @param biomes    biomes this variant can spawn in, if limited to specific biomes
 */
 public record AnimalVariant(int modelType, String texture, @Nullable HolderSet biomes) {

@@ -38,7 +38,7 @@ public interface EitherHolder<T> {
    /**
     * Returns an indirect holder via the resource key.
     *
-     * @param key  the resource key
+     * @param key the resource key
     * @param <T> the type of the value
     * @return a new holder with the given resource key
     */
@@ -22,6 +22,7 @@
 */
 package com.viaversion.viaversion.api.minecraft;

+import com.google.common.base.Preconditions;
 import com.viaversion.nbt.tag.ListTag;
 import com.viaversion.nbt.tag.StringTag;
 import com.viaversion.nbt.tag.Tag;
@@ -40,6 +41,7 @@ public interface HolderSet {
     * @return a new holder set
     */
    static HolderSet of(final String tagKey) {
+        Preconditions.checkNotNull(tagKey);
        return new HolderSetImpl.Tag(tagKey);
    }

@@ -50,6 +52,7 @@ public interface HolderSet {
     * @return a new holder set
     */
    static HolderSet of(final int[] ids) {
+        Preconditions.checkNotNull(ids);
        return new HolderSetImpl.Ids(ids);
    }

@@ -34,7 +34,9 @@ public enum RegistryType implements RegistryKey {
    FLUID("fluid"),
    ENTITY("entity_type"),
    GAME_EVENT("game_event"),
-    ENCHANTMENT("enchantment");
+    ENCHANTMENT("enchantment"),
+    DAMAGE_TYPE("damage_type"),
+    BANNER_PATTERN("banner_pattern");

    private static final Map<String, RegistryType> MAP = new HashMap<>();
    private static final RegistryType[] VALUES = values();
@@ -61,6 +61,17 @@ public interface ChunkSection {

    void setNonAirBlocksCount(int nonAirBlocksCount);

+    /**
+     * Returns the number of fluid blocks in this section.
+     * <p>
+     * Available with versions 26.1+.
+     *
+     * @return fluid blocks in this section
+     */
+    int getFluidCount();
+
+    void setFluidCount(int fluidCount);
+
    /**
     * Returns whether this section holds light data.
     * Only true for &lt; 1.14 chunks.
@@ -30,6 +30,7 @@ public class ChunkSectionImpl implements ChunkSection {
    private final EnumMap<PaletteType, DataPalette> palettes = new EnumMap<>(PaletteType.class);
    private ChunkSectionLight light;
    private int nonAirBlocksCount;
+    private int fluidCount;

    public ChunkSectionImpl() {
    }
@@ -58,6 +59,16 @@ public class ChunkSectionImpl implements ChunkSection {
        this.nonAirBlocksCount = nonAirBlocksCount;
    }

+    @Override
+    public int getFluidCount() {
+        return fluidCount;
+    }
+
+    @Override
+    public void setFluidCount(final int fluidCount) {
+        this.fluidCount = fluidCount;
+    }
+
    @Override
    public @Nullable ChunkSectionLight getLight() {
        return light;
@@ -163,7 +163,7 @@ public final class DataPaletteImpl implements DataPalette {
        }
    }

-    private class ByteChunkData implements ChunkData {
+    private final class ByteChunkData implements ChunkData {
        private final byte[] data;

        public ByteChunkData(int size) {
@@ -187,7 +187,7 @@ public final class DataPaletteImpl implements DataPalette {
        }
    }

-    private static class ShortChunkData implements ChunkData {
+    private static final class ShortChunkData implements ChunkData {
        private final short[] data;

        public ShortChunkData(byte[] data) {
@@ -53,7 +53,7 @@ public interface CodecContext {
         * Returns the key for a stored mapping type and its numeric id.
         *
         * @param mappingType mapping type
-         * @param id numeric id
+         * @param id          numeric id
         * @return the key
         */
        Key key(MappingData.MappingType mappingType, int id);
@@ -62,7 +62,7 @@ public interface CodecContext {
         * Returns the numeric id for a stored mapping type and its identifier.
         *
         * @param mappingType mapping type
-         * @param identifier identifier
+         * @param identifier  identifier
         * @return the numeric id, or -1 if not found
         */
        int id(MappingData.MappingType mappingType, String identifier);
@@ -75,7 +75,7 @@ public interface CodecContext {
         * Returns the key for a client-synchronized registry element.
         *
         * @param registry registry key
-         * @param id numeric id
+         * @param id       numeric id
         * @return the key
         */
        Key registryKey(String registry, int id);
@@ -81,12 +81,12 @@ public interface Ops {
        /**
         * Writes the given value or default value if the value is null.
         *
-         * @param key map key
-         * @param type type of the value
+         * @param key   map key
+         * @param type  type of the value
         * @param value the value to write, or null
-         * @param def default value to write if the value is null
+         * @param def   default value to write if the value is null
+         * @param <V>   value type
         * @return self
-         * @param <V> value type
         */
        default <V> MapSerializer write(final String key, final Type<V> type, @Nullable final V value, final V def) {
            write(Types.STRING, key, type, value != null ? value : def);
@@ -96,11 +96,11 @@ public interface Ops {
        /**
         * Writes the given value if it is not null.
         *
-         * @param key map key
-         * @param type type of the value
+         * @param key   map key
+         * @param type  type of the value
         * @param value the value to write, or null
+         * @param <V>   value type
         * @return self
-         * @param <V> value type
         */
        default <V> MapSerializer writeOptional(final String key, final Type<V> type, @Nullable final V value) {
            if (value != null) {
@@ -112,12 +112,12 @@ public interface Ops {
        /**
         * Writes the given value if it is not null and not equal to the default value.
         *
-         * @param key map key
-         * @param type type of the value
+         * @param key   map key
+         * @param type  type of the value
         * @param value the value to write, or null
-         * @param def default value to compare against
+         * @param def   default value to compare against
+         * @param <V>   value type
         * @return self
-         * @param <V> value type
         */
        default <V> MapSerializer writeOptional(final String key, final Type<V> type, @Nullable final V value, final V def) {
            if (value != null && !Objects.deepEquals(value, def)) {
@@ -37,6 +37,7 @@ import com.viaversion.viaversion.api.minecraft.data.version.StructuredDataKeys1_
 import com.viaversion.viaversion.api.minecraft.data.version.StructuredDataKeys1_21_5;
 import com.viaversion.viaversion.api.minecraft.item.data.AdventureModePredicate;
 import com.viaversion.viaversion.api.minecraft.item.data.ArmorTrim;
+import com.viaversion.viaversion.api.minecraft.item.data.ArmorTrimMaterial;
 import com.viaversion.viaversion.api.minecraft.item.data.AttackRange;
 import com.viaversion.viaversion.api.minecraft.item.data.AttributeModifiers1_20_5;
 import com.viaversion.viaversion.api.minecraft.item.data.AttributeModifiers1_21;
@@ -47,7 +48,8 @@ import com.viaversion.viaversion.api.minecraft.item.data.BlockStateProperties;
 import com.viaversion.viaversion.api.minecraft.item.data.BlocksAttacks;
 import com.viaversion.viaversion.api.minecraft.item.data.Consumable1_21_2;
 import com.viaversion.viaversion.api.minecraft.item.data.CustomModelData1_21_4;
-import com.viaversion.viaversion.api.minecraft.item.data.DamageResistant;
+import com.viaversion.viaversion.api.minecraft.item.data.DamageResistant1_21_2;
+import com.viaversion.viaversion.api.minecraft.item.data.DamageResistant26_1;
 import com.viaversion.viaversion.api.minecraft.item.data.DamageType;
 import com.viaversion.viaversion.api.minecraft.item.data.DeathProtection;
 import com.viaversion.viaversion.api.minecraft.item.data.DebugStickState;
@@ -65,12 +67,14 @@ import com.viaversion.viaversion.api.minecraft.item.data.Instrument1_20_5;
 import com.viaversion.viaversion.api.minecraft.item.data.Instrument1_21_2;
 import com.viaversion.viaversion.api.minecraft.item.data.ItemModel;
 import com.viaversion.viaversion.api.minecraft.item.data.JukeboxPlayable;
+import com.viaversion.viaversion.api.minecraft.item.data.JukeboxPlayable.JukeboxSong;
 import com.viaversion.viaversion.api.minecraft.item.data.KineticWeapon;
 import com.viaversion.viaversion.api.minecraft.item.data.LockCode;
 import com.viaversion.viaversion.api.minecraft.item.data.LodestoneTracker;
 import com.viaversion.viaversion.api.minecraft.item.data.PiercingWeapon;
 import com.viaversion.viaversion.api.minecraft.item.data.PotDecorations;
 import com.viaversion.viaversion.api.minecraft.item.data.PotionContents;
+import com.viaversion.viaversion.api.minecraft.item.data.ProvidesBannerPatterns;
 import com.viaversion.viaversion.api.minecraft.item.data.ProvidesTrimMaterial;
 import com.viaversion.viaversion.api.minecraft.item.data.Repairable;
 import com.viaversion.viaversion.api.minecraft.item.data.SuspiciousStewEffect;
@@ -98,8 +102,8 @@ import com.viaversion.viaversion.util.Unit;
 * Holds data component keys.
 *
 * @param identifier string identifier
- * @param type data type
- * @param <T> data type
+ * @param type       data type
+ * @param <T>        data type
 * @see VersionedTypes
 */
 public record StructuredDataKey<T>(String identifier, Type<T> type) {
@@ -113,7 +117,8 @@ public record StructuredDataKey<T>(String identifier, Type<T> type) {
    public static final StructuredDataKey<Unit> UNBREAKABLE1_21_5 = new StructuredDataKey<>("unbreakable", Types.EMPTY);
    public static final StructuredDataKey<Tag> CUSTOM_NAME = new StructuredDataKey<>("custom_name", Types.TEXT_COMPONENT_TAG);
    public static final StructuredDataKey<Float> MINIMUM_ATTACK_CHARGE = new StructuredDataKey<>("minimum_attack_charge", Types.FLOAT);
-    public static final StructuredDataKey<DamageType> DAMAGE_TYPE = new StructuredDataKey<>("damage_type", DamageType.TYPE);
+    public static final StructuredDataKey<DamageType> DAMAGE_TYPE1_21_11 = new StructuredDataKey<>("damage_type", DamageType.TYPE1_21_11);
+    public static final StructuredDataKey<Integer> DAMAGE_TYPE26_1 = new StructuredDataKey<>("damage_type", new SynchronizedRegistryValueType(RegistryKey.of("damage_type")));
    public static final StructuredDataKey<Tag> ITEM_NAME = new StructuredDataKey<>("item_name", Types.TEXT_COMPONENT_TAG);
    public static final StructuredDataKey<ItemModel> ITEM_MODEL = new StructuredDataKey<>("item_model", ItemModel.TYPE);
    public static final StructuredDataKey<Tag[]> LORE = new StructuredDataKey<>("lore", new ArrayType<>(Types.TEXT_COMPONENT_TAG, 256));
@@ -142,7 +147,8 @@ public record StructuredDataKey<T>(String identifier, Type<T> type) {
    public static final StructuredDataKey<Consumable1_21_2> CONSUMABLE1_21_2 = new StructuredDataKey<>("consumable", Consumable1_21_2.TYPE);
    public static final StructuredDataKey<UseCooldown> USE_COOLDOWN = new StructuredDataKey<>("use_cooldown", UseCooldown.TYPE);
    public static final StructuredDataKey<Unit> FIRE_RESISTANT = new StructuredDataKey<>("fire_resistant", Types.EMPTY);
-    public static final StructuredDataKey<DamageResistant> DAMAGE_RESISTANT = new StructuredDataKey<>("damage_resistant", DamageResistant.TYPE);
+    public static final StructuredDataKey<DamageResistant1_21_2> DAMAGE_RESISTANT1_21_2 = new StructuredDataKey<>("damage_resistant", DamageResistant1_21_2.TYPE);
+    public static final StructuredDataKey<DamageResistant26_1> DAMAGE_RESISTANT26_1 = new StructuredDataKey<>("damage_resistant", DamageResistant26_1.TYPE);
    public static final StructuredDataKey<ToolProperties> TOOL1_20_5 = new StructuredDataKey<>("tool", ToolProperties.TYPE1_20_5);
    public static final StructuredDataKey<ToolProperties> TOOL1_21_5 = new StructuredDataKey<>("tool", ToolProperties.TYPE1_21_5);
    public static final StructuredDataKey<Weapon> WEAPON = new StructuredDataKey<>("weapon", Weapon.TYPE);
@@ -155,12 +161,15 @@ public record StructuredDataKey<T>(String identifier, Type<T> type) {
    public static final StructuredDataKey<Unit> GLIDER = new StructuredDataKey<>("glider", Types.EMPTY);
    public static final StructuredDataKey<Key> TOOLTIP_STYLE = new StructuredDataKey<>("tooltip_style", Types.IDENTIFIER);
    public static final StructuredDataKey<DeathProtection> DEATH_PROTECTION = new StructuredDataKey<>("death_protection", DeathProtection.TYPE);
-    public static final StructuredDataKey<BlocksAttacks> BLOCKS_ATTACKS = new StructuredDataKey<>("blocks_attacks", BlocksAttacks.TYPE);
+    public static final StructuredDataKey<BlocksAttacks> BLOCKS_ATTACKS1_21_5 = new StructuredDataKey<>("blocks_attacks", BlocksAttacks.TYPE1_21_5);
+    public static final StructuredDataKey<BlocksAttacks> BLOCKS_ATTACKS26_1 = new StructuredDataKey<>("blocks_attacks", BlocksAttacks.TYPE26_1);
    public static final StructuredDataKey<PiercingWeapon> PIERCING_WEAPON = new StructuredDataKey<>("piercing_weapon", PiercingWeapon.TYPE);
    public static final StructuredDataKey<KineticWeapon> KINETIC_WEAPON = new StructuredDataKey<>("kinetic_weapon", KineticWeapon.TYPE);
    public static final StructuredDataKey<SwingAnimation> SWING_ANIMATION = new StructuredDataKey<>("swing_animation", SwingAnimation.TYPE);
+    public static final StructuredDataKey<Integer> ADDITIONAL_TRADE_COST = new StructuredDataKey<>("additional_trade_cost", Types.VAR_INT);
    public static final StructuredDataKey<Enchantments> STORED_ENCHANTMENTS1_20_5 = new StructuredDataKey<>("stored_enchantments", Enchantments.TYPE1_20_5);
    public static final StructuredDataKey<Enchantments> STORED_ENCHANTMENTS1_21_5 = new StructuredDataKey<>("stored_enchantments", Enchantments.TYPE1_21_5);
+    public static final StructuredDataKey<Integer> DYE = new StructuredDataKey<>("dye", EnumTypes.DYE_COLOR);
    public static final StructuredDataKey<DyedColor> DYED_COLOR1_20_5 = new StructuredDataKey<>("dyed_color", DyedColor.TYPE1_20_5);
    public static final StructuredDataKey<DyedColor> DYED_COLOR1_21_5 = new StructuredDataKey<>("dyed_color", DyedColor.TYPE1_21_5);
    public static final StructuredDataKey<Integer> MAP_COLOR = new StructuredDataKey<>("map_color", Types.INT);
@@ -186,11 +195,15 @@ public record StructuredDataKey<T>(String identifier, Type<T> type) {
    public static final StructuredDataKey<Holder<Instrument1_20_5>> INSTRUMENT1_20_5 = new StructuredDataKey<>("instrument", Instrument1_20_5.TYPE);
    public static final StructuredDataKey<Holder<Instrument1_21_2>> INSTRUMENT1_21_2 = new StructuredDataKey<>("instrument", Instrument1_21_2.TYPE);
    public static final StructuredDataKey<EitherHolder<Instrument1_21_2>> INSTRUMENT1_21_5 = new StructuredDataKey<>("instrument", Instrument1_21_2.EITHER_HOLDER_TYPE);
-    public static final StructuredDataKey<ProvidesTrimMaterial> PROVIDES_TRIM_MATERIAL = new StructuredDataKey<>("provides_trim_material", ProvidesTrimMaterial.TYPE);
+    public static final StructuredDataKey<Holder<Instrument1_21_2>> INSTRUMENT26_1 = new StructuredDataKey<>("instrument", Instrument1_21_2.TYPE);
+    public static final StructuredDataKey<ProvidesTrimMaterial> PROVIDES_TRIM_MATERIAL1_21_5 = new StructuredDataKey<>("provides_trim_material", ProvidesTrimMaterial.TYPE);
+    public static final StructuredDataKey<Holder<ArmorTrimMaterial>> PROVIDES_TRIM_MATERIAL26_1 = new StructuredDataKey<>("provides_trim_material", ArmorTrimMaterial.TYPE1_21_5);
    public static final StructuredDataKey<Integer> OMINOUS_BOTTLE_AMPLIFIER = new StructuredDataKey<>("ominous_bottle_amplifier", Types.VAR_INT);
    public static final StructuredDataKey<JukeboxPlayable> JUKEBOX_PLAYABLE1_21 = new StructuredDataKey<>("jukebox_playable", JukeboxPlayable.TYPE1_21);
    public static final StructuredDataKey<JukeboxPlayable> JUKEBOX_PLAYABLE1_21_5 = new StructuredDataKey<>("jukebox_playable", JukeboxPlayable.TYPE1_21_5);
-    public static final StructuredDataKey<Key> PROVIDES_BANNER_PATTERNS = new StructuredDataKey<>("provides_banner_patterns", Types.TAG_KEY);
+    public static final StructuredDataKey<Holder<JukeboxSong>> JUKEBOX_PLAYABLE26_1 = new StructuredDataKey<>("jukebox_playable", JukeboxSong.TYPE);
+    public static final StructuredDataKey<Key> PROVIDES_BANNER_PATTERNS1_21_5 = new StructuredDataKey<>("provides_banner_patterns", Types.TAG_KEY);
+    public static final StructuredDataKey<ProvidesBannerPatterns> PROVIDES_BANNER_PATTERNS26_1 = new StructuredDataKey<>("provides_banner_patterns", ProvidesBannerPatterns.TYPE);
    public static final StructuredDataKey<Tag> RECIPES = new StructuredDataKey<>("recipes", Types.TAG);
    public static final StructuredDataKey<LodestoneTracker> LODESTONE_TRACKER = new StructuredDataKey<>("lodestone_tracker", LodestoneTracker.TYPE);
    public static final StructuredDataKey<FireworkExplosion> FIREWORK_EXPLOSION = new StructuredDataKey<>("firework_explosion", FireworkExplosion.TYPE);
@@ -223,8 +236,10 @@ public record StructuredDataKey<T>(String identifier, Type<T> type) {
    public static final StructuredDataKey<Integer> RABBIT_VARIANT = new StructuredDataKey<>("rabbit/variant", EnumTypes.RABBIT_VARIANT);
    public static final StructuredDataKey<Integer> PIG_VARIANT = new StructuredDataKey<>("pig/variant", new SynchronizedRegistryValueType(RegistryKey.of("pig_variant")));
    public static final StructuredDataKey<Integer> COW_VARIANT = new StructuredDataKey<>("cow/variant", new SynchronizedRegistryValueType(RegistryKey.of("cow_variant")));
-    public static final StructuredDataKey<Either<Integer, String>> CHICKEN_VARIANT = new StructuredDataKey<>("chicken/variant", new SynchronizedRegistryEitherType(RegistryKey.of("chicken_variant")));
-    public static final StructuredDataKey<Either<Integer, String>> ZOMBIE_NAUTILUS_VARIANT = new StructuredDataKey<>("zombie_nautilus/variant", new SynchronizedRegistryEitherType(RegistryKey.of("zombie_nautilus_variant"))); // ???
+    public static final StructuredDataKey<Either<Integer, String>> CHICKEN_VARIANT1_21_5 = new StructuredDataKey<>("chicken/variant", new SynchronizedRegistryEitherType(RegistryKey.of("chicken_variant")));
+    public static final StructuredDataKey<Integer> CHICKEN_VARIANT26_1 = new StructuredDataKey<>("chicken/variant", new SynchronizedRegistryValueType(RegistryKey.of("chicken_variant")));
+    public static final StructuredDataKey<Either<Integer, String>> ZOMBIE_NAUTILUS_VARIANT1_21_11 = new StructuredDataKey<>("zombie_nautilus/variant", new SynchronizedRegistryEitherType(RegistryKey.of("zombie_nautilus_variant"))); // ???
+    public static final StructuredDataKey<Integer> ZOMBIE_NAUTILUS_VARIANT26_1 = new StructuredDataKey<>("zombie_nautilus/variant", new SynchronizedRegistryValueType(RegistryKey.of("zombie_nautilus_variant")));
    public static final StructuredDataKey<Integer> FROG_VARIANT = new StructuredDataKey<>("frog/variant", new SynchronizedRegistryValueType(RegistryKey.of("frog_variant")));
    public static final StructuredDataKey<Integer> HORSE_VARIANT = new StructuredDataKey<>("horse/variant", EnumTypes.HORSE_VARIANT);
    public static final StructuredDataKey<Holder<PaintingVariant>> PAINTING_VARIANT = new StructuredDataKey<>("painting/variant", PaintingVariant.TYPE1_21_2);
@@ -234,6 +249,10 @@ public record StructuredDataKey<T>(String identifier, Type<T> type) {
    public static final StructuredDataKey<Integer> CAT_COLLAR = new StructuredDataKey<>("cat/collar", EnumTypes.DYE_COLOR);
    public static final StructuredDataKey<Integer> SHEEP_COLOR = new StructuredDataKey<>("sheep/color", EnumTypes.DYE_COLOR);
    public static final StructuredDataKey<Integer> SHULKER_COLOR = new StructuredDataKey<>("shulker/color", EnumTypes.DYE_COLOR);
+    public static final StructuredDataKey<Integer> PIG_SOUND_VARIANT = new StructuredDataKey<>("pig/sound_variant", new SynchronizedRegistryValueType(RegistryKey.of("pig_sound_variant")));
+    public static final StructuredDataKey<Integer> COW_SOUND_VARIANT = new StructuredDataKey<>("cow/sound_variant", new SynchronizedRegistryValueType(RegistryKey.of("cow_sound_variant")));
+    public static final StructuredDataKey<Integer> CHICKEN_SOUND_VARIANT = new StructuredDataKey<>("chicken/sound_variant", new SynchronizedRegistryValueType(RegistryKey.of("chicken_sound_variant")));
+    public static final StructuredDataKey<Integer> CAT_SOUND_VARIANT = new StructuredDataKey<>("cat/sound_variant", new SynchronizedRegistryValueType(RegistryKey.of("cat_sound_variant")));

    // These are only safe to use after protocol loading
    public static final StructuredDataKeys1_20_5 V1_20_5 = VersionedTypes.V1_20_5.structuredDataKeys();
@@ -35,9 +35,9 @@ public class StructuredDataKeys1_21_2 extends VersionedStructuredDataKeys {
    public final StructuredDataKey<Item> useRemainder;

    public StructuredDataKeys1_21_2(final VersionedTypesHolder types) {
-        this.container = add("container", new ContainerContentsType(types.item()));
-        this.chargedProjectiles = add("charged_projectiles", types.itemArray());
-        this.bundleContents = add("bundle_contents", types.itemArray());
-        this.useRemainder = add("use_remainder", types.item());
+        this.container = add("container", new ContainerContentsType(types.optionalItemTemplate()));
+        this.chargedProjectiles = add("charged_projectiles", types.itemTemplateArray());
+        this.bundleContents = add("bundle_contents", types.itemTemplateArray());
+        this.useRemainder = add("use_remainder", types.itemTemplate());
    }
 }
@@ -145,13 +145,13 @@ public enum EntityTypes1_14 implements EntityType {
    SHEEP(ABSTRACT_ANIMAL),
    TURTLE(ABSTRACT_ANIMAL),
    FOX(ABSTRACT_ANIMAL),
+    OCELOT(ABSTRACT_ANIMAL),

    COW(ABSTRACT_ANIMAL),
    MOOSHROOM(COW),

    TAMABLE_ANIMAL(ABSTRACT_ANIMAL, null),
    CAT(TAMABLE_ANIMAL),
-    OCELOT(TAMABLE_ANIMAL),
    WOLF(TAMABLE_ANIMAL),
    PARROT(TAMABLE_ANIMAL),

@@ -146,13 +146,13 @@ public enum EntityTypes1_15 implements EntityType {
    BEE(ABSTRACT_ANIMAL),
    TURTLE(ABSTRACT_ANIMAL),
    FOX(ABSTRACT_ANIMAL),
+    OCELOT(ABSTRACT_ANIMAL),

    COW(ABSTRACT_ANIMAL),
    MOOSHROOM(COW),

    TAMABLE_ANIMAL(ABSTRACT_ANIMAL, null),
    CAT(TAMABLE_ANIMAL),
-    OCELOT(TAMABLE_ANIMAL),
    WOLF(TAMABLE_ANIMAL),
    PARROT(TAMABLE_ANIMAL),

@@ -148,13 +148,13 @@ public enum EntityTypes1_16 implements EntityType {
    FOX(ABSTRACT_ANIMAL),
    HOGLIN(ABSTRACT_ANIMAL),
    STRIDER(ABSTRACT_ANIMAL),
+    OCELOT(ABSTRACT_ANIMAL),

    COW(ABSTRACT_ANIMAL),
    MOOSHROOM(COW),

    TAMABLE_ANIMAL(ABSTRACT_ANIMAL, null),
    CAT(TAMABLE_ANIMAL),
-    OCELOT(TAMABLE_ANIMAL),
    WOLF(TAMABLE_ANIMAL),
    PARROT(TAMABLE_ANIMAL),

@@ -148,13 +148,13 @@ public enum EntityTypes1_16_2 implements EntityType {
    FOX(ABSTRACT_ANIMAL),
    HOGLIN(ABSTRACT_ANIMAL),
    STRIDER(ABSTRACT_ANIMAL),
+    OCELOT(ABSTRACT_ANIMAL),

    COW(ABSTRACT_ANIMAL),
    MOOSHROOM(COW),

    TAMABLE_ANIMAL(ABSTRACT_ANIMAL, null),
    CAT(TAMABLE_ANIMAL),
-    OCELOT(TAMABLE_ANIMAL),
    WOLF(TAMABLE_ANIMAL),
    PARROT(TAMABLE_ANIMAL),

@@ -154,13 +154,13 @@ public enum EntityTypes1_17 implements EntityType {
    GOAT(ABSTRACT_ANIMAL),
    HOGLIN(ABSTRACT_ANIMAL),
    STRIDER(ABSTRACT_ANIMAL),
+    OCELOT(ABSTRACT_ANIMAL),

    COW(ABSTRACT_ANIMAL),
    MOOSHROOM(COW),

    TAMABLE_ANIMAL(ABSTRACT_ANIMAL, null),
    CAT(TAMABLE_ANIMAL),
-    OCELOT(TAMABLE_ANIMAL),
    WOLF(TAMABLE_ANIMAL),
    PARROT(TAMABLE_ANIMAL),

@@ -158,13 +158,13 @@ public enum EntityTypes1_19 implements EntityType {
    GOAT(ABSTRACT_ANIMAL),
    HOGLIN(ABSTRACT_ANIMAL),
    STRIDER(ABSTRACT_ANIMAL),
+    OCELOT(ABSTRACT_ANIMAL),

    COW(ABSTRACT_ANIMAL),
    MOOSHROOM(COW),

    TAMABLE_ANIMAL(ABSTRACT_ANIMAL, null),
    CAT(TAMABLE_ANIMAL),
-    OCELOT(TAMABLE_ANIMAL),
    WOLF(TAMABLE_ANIMAL),
    PARROT(TAMABLE_ANIMAL),

@@ -158,13 +158,13 @@ public enum EntityTypes1_19_3 implements EntityType {
    GOAT(ABSTRACT_ANIMAL),
    HOGLIN(ABSTRACT_ANIMAL),
    STRIDER(ABSTRACT_ANIMAL),
+    OCELOT(ABSTRACT_ANIMAL),

    COW(ABSTRACT_ANIMAL),
    MOOSHROOM(COW),

    TAMABLE_ANIMAL(ABSTRACT_ANIMAL, null),
    CAT(TAMABLE_ANIMAL),
-    OCELOT(TAMABLE_ANIMAL),
    WOLF(TAMABLE_ANIMAL),
    PARROT(TAMABLE_ANIMAL),

@@ -165,13 +165,13 @@ public enum EntityTypes1_19_4 implements EntityType {
    HOGLIN(ABSTRACT_ANIMAL),
    STRIDER(ABSTRACT_ANIMAL),
    SNIFFER(ABSTRACT_ANIMAL),
+    OCELOT(ABSTRACT_ANIMAL),

    COW(ABSTRACT_ANIMAL),
    MOOSHROOM(COW),

    TAMABLE_ANIMAL(ABSTRACT_ANIMAL, null),
    CAT(TAMABLE_ANIMAL),
-    OCELOT(TAMABLE_ANIMAL),
    WOLF(TAMABLE_ANIMAL),
    PARROT(TAMABLE_ANIMAL),

@@ -166,13 +166,13 @@ public enum EntityTypes1_20_3 implements EntityType {
    HOGLIN(ABSTRACT_ANIMAL),
    STRIDER(ABSTRACT_ANIMAL),
    SNIFFER(ABSTRACT_ANIMAL),
+    OCELOT(ABSTRACT_ANIMAL),

    COW(ABSTRACT_ANIMAL),
    MOOSHROOM(COW),

    TAMABLE_ANIMAL(ABSTRACT_ANIMAL, null),
    CAT(TAMABLE_ANIMAL),
-    OCELOT(TAMABLE_ANIMAL),
    WOLF(TAMABLE_ANIMAL),
    PARROT(TAMABLE_ANIMAL),

@@ -171,13 +171,13 @@ public enum EntityTypes1_20_5 implements EntityType {
    STRIDER(ABSTRACT_ANIMAL),
    SNIFFER(ABSTRACT_ANIMAL),
    ARMADILLO(ABSTRACT_ANIMAL),
+    OCELOT(ABSTRACT_ANIMAL),

    COW(ABSTRACT_ANIMAL),
    MOOSHROOM(COW),

    TAMABLE_ANIMAL(ABSTRACT_ANIMAL, null),
    CAT(TAMABLE_ANIMAL),
-    OCELOT(TAMABLE_ANIMAL),
    WOLF(TAMABLE_ANIMAL),
    PARROT(TAMABLE_ANIMAL),

@@ -185,6 +185,7 @@ public enum EntityTypes1_21_11 implements EntityType {
    SNIFFER(ABSTRACT_ANIMAL),
    ARMADILLO(ABSTRACT_ANIMAL),
    HAPPY_GHAST(ABSTRACT_ANIMAL),
+    OCELOT(ABSTRACT_ANIMAL),

    ABSTRACT_COW(ABSTRACT_ANIMAL, null),
    COW(ABSTRACT_COW),
@@ -192,7 +193,6 @@ public enum EntityTypes1_21_11 implements EntityType {

    TAMABLE_ANIMAL(ABSTRACT_ANIMAL, null),
    CAT(TAMABLE_ANIMAL),
-    OCELOT(TAMABLE_ANIMAL),
    WOLF(TAMABLE_ANIMAL),
    PARROT(TAMABLE_ANIMAL),

@@ -176,13 +176,13 @@ public enum EntityTypes1_21_2 implements EntityType {
    STRIDER(ABSTRACT_ANIMAL),
    SNIFFER(ABSTRACT_ANIMAL),
    ARMADILLO(ABSTRACT_ANIMAL),
+    OCELOT(ABSTRACT_ANIMAL),

    COW(ABSTRACT_ANIMAL),
    MOOSHROOM(COW),

    TAMABLE_ANIMAL(ABSTRACT_ANIMAL, null),
    CAT(TAMABLE_ANIMAL),
-    OCELOT(TAMABLE_ANIMAL),
    WOLF(TAMABLE_ANIMAL),
    PARROT(TAMABLE_ANIMAL),

@@ -176,13 +176,13 @@ public enum EntityTypes1_21_4 implements EntityType {
    STRIDER(ABSTRACT_ANIMAL),
    SNIFFER(ABSTRACT_ANIMAL),
    ARMADILLO(ABSTRACT_ANIMAL),
+    OCELOT(ABSTRACT_ANIMAL),

    COW(ABSTRACT_ANIMAL),
    MOOSHROOM(COW),

    TAMABLE_ANIMAL(ABSTRACT_ANIMAL, null),
    CAT(TAMABLE_ANIMAL),
-    OCELOT(TAMABLE_ANIMAL),
    WOLF(TAMABLE_ANIMAL),
    PARROT(TAMABLE_ANIMAL),

@@ -179,6 +179,7 @@ public enum EntityTypes1_21_5 implements EntityType {
    STRIDER(ABSTRACT_ANIMAL),
    SNIFFER(ABSTRACT_ANIMAL),
    ARMADILLO(ABSTRACT_ANIMAL),
+    OCELOT(ABSTRACT_ANIMAL),

    ABSTRACT_COW(ABSTRACT_ANIMAL, null),
    COW(ABSTRACT_COW),
@@ -186,7 +187,6 @@ public enum EntityTypes1_21_5 implements EntityType {

    TAMABLE_ANIMAL(ABSTRACT_ANIMAL, null),
    CAT(TAMABLE_ANIMAL),
-    OCELOT(TAMABLE_ANIMAL),
    WOLF(TAMABLE_ANIMAL),
    PARROT(TAMABLE_ANIMAL),

@@ -180,6 +180,7 @@ public enum EntityTypes1_21_6 implements EntityType {
    SNIFFER(ABSTRACT_ANIMAL),
    ARMADILLO(ABSTRACT_ANIMAL),
    HAPPY_GHAST(ABSTRACT_ANIMAL),
+    OCELOT(ABSTRACT_ANIMAL),

    ABSTRACT_COW(ABSTRACT_ANIMAL, null),
    COW(ABSTRACT_COW),
@@ -187,7 +188,6 @@ public enum EntityTypes1_21_6 implements EntityType {

    TAMABLE_ANIMAL(ABSTRACT_ANIMAL, null),
    CAT(TAMABLE_ANIMAL),
-    OCELOT(TAMABLE_ANIMAL),
    WOLF(TAMABLE_ANIMAL),
    PARROT(TAMABLE_ANIMAL),

@@ -185,6 +185,7 @@ public enum EntityTypes1_21_9 implements EntityType {
    SNIFFER(ABSTRACT_ANIMAL),
    ARMADILLO(ABSTRACT_ANIMAL),
    HAPPY_GHAST(ABSTRACT_ANIMAL),
+    OCELOT(ABSTRACT_ANIMAL),

    ABSTRACT_COW(ABSTRACT_ANIMAL, null),
    COW(ABSTRACT_COW),
@@ -192,7 +193,6 @@ public enum EntityTypes1_21_9 implements EntityType {

    TAMABLE_ANIMAL(ABSTRACT_ANIMAL, null),
    CAT(TAMABLE_ANIMAL),
-    OCELOT(TAMABLE_ANIMAL),
    WOLF(TAMABLE_ANIMAL),
    PARROT(TAMABLE_ANIMAL),

@@ -43,6 +43,10 @@ public abstract class AbstractEntityDataTypes implements EntityDataTypes {
        return values;
    }

+    public Class<? extends EntityDataType> getDataTypeClass() {
+        return byId(0).getClass();
+    }
+
    protected EntityDataType add(final int typeId, final Type<?> type) {
        if (values[typeId] != null) {
            throw new IllegalArgumentException("Entity data type ID " + typeId + " is already registered as " + values[typeId]);
@@ -47,7 +47,7 @@ public final class EntityDataTypes1_21_11 extends AbstractEntityDataTypes {
    public final EntityDataType optionalBlockStateType = add(15, Types.VAR_INT);
    public final EntityDataType particleType;
    public final EntityDataType particlesType;
-    public final EntityDataType villagerDatatType = add(18, Types.VILLAGER_DATA);
+    public final EntityDataType villagerDataType = add(18, Types.VILLAGER_DATA);
    public final EntityDataType optionalVarIntType = add(19, Types.OPTIONAL_VAR_INT);
    public final EntityDataType poseType = add(20, Types.VAR_INT);
    public final EntityDataType catVariantType = add(21, Types.VAR_INT);
@@ -0,0 +1,82 @@
+/*
+ * This file is part of ViaVersion - https://github.com/ViaVersion/ViaVersion
+ * Copyright (C) 2016-2026 ViaVersion and contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+package com.viaversion.viaversion.api.minecraft.entitydata.types;
+
+import com.viaversion.viaversion.api.minecraft.PaintingVariant;
+import com.viaversion.viaversion.api.minecraft.entitydata.EntityDataType;
+import com.viaversion.viaversion.api.type.Types;
+import com.viaversion.viaversion.api.type.types.version.VersionedTypesHolder;
+
+public final class EntityDataTypes26_1 extends AbstractEntityDataTypes {
+
+    public final EntityDataType byteType = add(0, Types.BYTE);
+    public final EntityDataType varIntType = add(1, Types.VAR_INT);
+    public final EntityDataType longType = add(2, Types.VAR_LONG);
+    public final EntityDataType floatType = add(3, Types.FLOAT);
+    public final EntityDataType stringType = add(4, Types.STRING);
+    public final EntityDataType componentType = add(5, Types.TRUSTED_TAG);
+    public final EntityDataType optionalComponentType = add(6, Types.TRUSTED_OPTIONAL_TAG);
+    public final EntityDataType itemType;
+    public final EntityDataType booleanType = add(8, Types.BOOLEAN);
+    public final EntityDataType rotationsType = add(9, Types.ROTATIONS);
+    public final EntityDataType blockPositionType = add(10, Types.BLOCK_POSITION1_14);
+    public final EntityDataType optionalBlockPositionType = add(11, Types.OPTIONAL_POSITION_1_14);
+    public final EntityDataType directionType = add(12, Types.VAR_INT);
+    public final EntityDataType optionalUUIDType = add(13, Types.OPTIONAL_UUID);
+    public final EntityDataType blockStateType = add(14, Types.VAR_INT);
+    public final EntityDataType optionalBlockStateType = add(15, Types.VAR_INT);
+    public final EntityDataType particleType;
+    public final EntityDataType particlesType;
+    public final EntityDataType villagerDataType = add(18, Types.VILLAGER_DATA);
+    public final EntityDataType optionalVarIntType = add(19, Types.OPTIONAL_VAR_INT);
+    public final EntityDataType poseType = add(20, Types.VAR_INT);
+    public final EntityDataType catVariantType = add(21, Types.VAR_INT);
+    public final EntityDataType catSoundVariant = add(22, Types.VAR_INT);
+    public final EntityDataType cowVariantType = add(23, Types.VAR_INT);
+    public final EntityDataType cowSoundVariant = add(24, Types.VAR_INT);
+    public final EntityDataType wolfVariantType = add(25, Types.VAR_INT);
+    public final EntityDataType wolfSoundVariantType = add(26, Types.VAR_INT);
+    public final EntityDataType frogVariantType = add(27, Types.VAR_INT);
+    public final EntityDataType pigVariantType = add(28, Types.VAR_INT);
+    public final EntityDataType pigSoundVariant = add(29, Types.VAR_INT);
+    public final EntityDataType chickenVariantType = add(30, Types.VAR_INT);
+    public final EntityDataType chickenSoundVariant = add(31, Types.VAR_INT);
+    public final EntityDataType zombieNautilusVariantType = add(32, Types.VAR_INT);
+    public final EntityDataType optionalGlobalPosition = add(33, Types.OPTIONAL_GLOBAL_POSITION);
+    public final EntityDataType paintingVariantType = add(34, PaintingVariant.TYPE1_21_2);
+    public final EntityDataType snifferState = add(35, Types.VAR_INT);
+    public final EntityDataType armadilloState = add(36, Types.VAR_INT);
+    public final EntityDataType copperGolemState = add(37, Types.VAR_INT);
+    public final EntityDataType weatheringCopperState = add(38, Types.VAR_INT);
+    public final EntityDataType vector3FType = add(39, Types.VECTOR3F);
+    public final EntityDataType quaternionType = add(40, Types.QUATERNION);
+    public final EntityDataType mannequinProfileType = add(41, Types.RESOLVABLE_PROFILE);
+    public final EntityDataType humanoidArmType = add(42, Types.VAR_INT);
+
+    public EntityDataTypes26_1(final VersionedTypesHolder types) {
+        super(43);
+        this.itemType = add(7, types.item());
+        this.particleType = add(16, types.particle());
+        this.particlesType = add(17, types.particles());
+    }
+}
@@ -76,4 +76,23 @@ public interface Item extends ItemBase {
     */
    @Override
    Item copy();
+
+    /**
+     * Returns whether the item is a template item.
+     *
+     * @return whether the item is a template item
+     */
+    default boolean isTemplate() {
+        return false;
+    }
+
+    /**
+     * Returns whether the item is null or empty.
+     *
+     * @param item item
+     * @return whether the item is null or empty
+     */
+    static boolean isEmpty(@Nullable final Item item) {
+        return item == null || item.isEmpty();
+    }
 }
@@ -0,0 +1,59 @@
+/*
+ * This file is part of ViaVersion - https://github.com/ViaVersion/ViaVersion
+ * Copyright (C) 2016-2026 ViaVersion and contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+package com.viaversion.viaversion.api.minecraft.item;
+
+import com.google.common.base.Preconditions;
+import com.viaversion.viaversion.api.minecraft.data.StructuredDataContainer;
+
+public class StructuredItemTemplate extends StructuredItem {
+
+    public StructuredItemTemplate(final int identifier, final int amount) {
+        super(identifier, amount, new StructuredDataContainer());
+    }
+
+    public StructuredItemTemplate(final int identifier, final int amount, final StructuredDataContainer data) {
+        super(identifier, amount, data);
+    }
+
+    @Override
+    public void setIdentifier(final int identifier) {
+        Preconditions.checkArgument(identifier > 0, "Template item cannot be empty");
+        super.setIdentifier(identifier);
+    }
+
+    @Override
+    public void setAmount(final int amount) {
+        Preconditions.checkArgument(amount > 0, "Template item cannot be empty");
+        super.setAmount(amount);
+    }
+
+    @Override
+    public boolean isTemplate() {
+        return true;
+    }
+
+    @Override
+    public StructuredItemTemplate copy() {
+        return new StructuredItemTemplate(identifier(), amount(), dataContainer().copy());
+    }
+}
@@ -56,8 +56,8 @@ public record AttackRange(float minRange, float maxRange,
        @Override
        public void write(final Ops ops, final AttackRange AttackRange) {
            ops.writeMap(map -> map
-                .writeOptional("min_range", Types.FLOAT, AttackRange.minRange, 0F)
-                .writeOptional("max_range", Types.FLOAT, AttackRange.maxRange, 3F)
+                .writeOptional("min_reach", Types.FLOAT, AttackRange.minRange, 0F)
+                .writeOptional("max_reach", Types.FLOAT, AttackRange.maxRange, 3F)
                .writeOptional("min_creative_reach", Types.FLOAT, AttackRange.minCreativeRange, 0F)
                .writeOptional("max_creative_reach", Types.FLOAT, AttackRange.maxCreativeRange, 5F)
                .writeOptional("hitbox_margin", Types.FLOAT, AttackRange.hitboxMargin, 0.3F)
@@ -37,6 +37,7 @@ import io.netty.buffer.ByteBuf;
 import it.unimi.dsi.fastutil.ints.Int2IntFunction;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Objects;

 public record AttributeModifiers1_21(AttributeModifier[] modifiers, boolean showInTooltip) implements Copyable, Rewritable {

@@ -226,7 +227,7 @@ public record AttributeModifiers1_21(AttributeModifier[] modifiers, boolean show
    }

    public static class Display implements Copyable {
-        public static final String[] DISPLAY_TYPES = {"default", "hidden", "override_text"};
+        public static final String[] DISPLAY_TYPES = {"default", "hidden", "override"};
        public static final Display DEFAULT = new Display(0);
        private final int id;

@@ -246,6 +247,17 @@ public record AttributeModifiers1_21(AttributeModifier[] modifiers, boolean show
        public Display copy() {
            return this;
        }
+
+        @Override
+        public boolean equals(final Object o) {
+            if (!(o instanceof final Display display)) return false;
+            return id == display.id;
+        }
+
+        @Override
+        public int hashCode() {
+            return id;
+        }
    }

    public static final class OverrideText extends Display {
@@ -271,5 +283,19 @@ public record AttributeModifiers1_21(AttributeModifier[] modifiers, boolean show
        public OverrideText copy() {
            return new OverrideText(this.component.copy());
        }
+
+        @Override
+        public boolean equals(final Object o) {
+            if (!(o instanceof final OverrideText that)) return false;
+            if (!super.equals(o)) return false;
+            return Objects.equals(component, that.component);
+        }
+
+        @Override
+        public int hashCode() {
+            int result = super.hashCode();
+            result = 31 * result + Objects.hashCode(component);
+            return result;
+        }
    }
 }
@@ -43,12 +43,12 @@ public record BlocksAttacks(
    float disableCooldownScale,
    DamageReduction[] damageReductions,
    ItemDamageFunction itemDamage,
-    @Nullable String bypassedByTag,
+    @Nullable HolderSet bypassedBy, // always a tag before 26.1
    @Nullable Holder<SoundEvent> blockSound,
    @Nullable Holder<SoundEvent> disableSound
 ) implements Rewritable {

-    public static final Type<BlocksAttacks> TYPE = new Type<>(BlocksAttacks.class) {
+    public static final Type<BlocksAttacks> TYPE1_21_5 = new Type<>(BlocksAttacks.class) {

        @Override
        public BlocksAttacks read(final ByteBuf buffer) {
@@ -59,7 +59,7 @@ public record BlocksAttacks(
            final String bypassedByTag = Types.OPTIONAL_STRING.read(buffer);
            final Holder<SoundEvent> blockSound = Types.OPTIONAL_SOUND_EVENT.read(buffer);
            final Holder<SoundEvent> disableSound = Types.OPTIONAL_SOUND_EVENT.read(buffer);
-            return new BlocksAttacks(blockDelaySeconds, disableCooldownScale, damageReductions, itemDamage, bypassedByTag, blockSound, disableSound);
+            return new BlocksAttacks(blockDelaySeconds, disableCooldownScale, damageReductions, itemDamage, bypassedByTag != null ? HolderSet.of(bypassedByTag) : null, blockSound, disableSound);
        }

        @Override
@@ -68,7 +68,7 @@ public record BlocksAttacks(
            buffer.writeFloat(value.disableCooldownScale());
            DamageReduction.ARRAY_TYPE.write(buffer, value.damageReductions());
            ItemDamageFunction.TYPE.write(buffer, value.itemDamage());
-            Types.OPTIONAL_STRING.write(buffer, value.bypassedByTag());
+            Types.OPTIONAL_STRING.write(buffer, value.bypassedBy() != null ? value.bypassedBy().tagKey() : null);
            Types.OPTIONAL_SOUND_EVENT.write(buffer, value.blockSound());
            Types.OPTIONAL_SOUND_EVENT.write(buffer, value.disableSound());
        }
@@ -82,7 +82,47 @@ public record BlocksAttacks(
                .writeOptional("disable_cooldown_scale", Types.FLOAT, value.disableCooldownScale(), 1F)
                .writeOptional("damage_reductions", DamageReduction.ARRAY_TYPE, value.damageReductions(), defaultDamageReductions)
                .writeOptional("item_damage", ItemDamageFunction.TYPE, value.itemDamage(), defaultItemDamage)
-                .writeOptional("bypassed_by", Types.TAG_KEY, value.bypassedByTag() != null ? Key.of(value.bypassedByTag()) : null)
+                .writeOptional("bypassed_by", Types.TAG_KEY, value.bypassedBy() != null ? Key.of(value.bypassedBy().tagKey()) : null)
+                .writeOptional("block_sound", Types.SOUND_EVENT, value.blockSound())
+                .writeOptional("disabled_sound", Types.SOUND_EVENT, value.disableSound()));
+        }
+    };
+
+    public static final Type<BlocksAttacks> TYPE26_1 = new Type<>(BlocksAttacks.class) {
+
+        @Override
+        public BlocksAttacks read(final ByteBuf buffer) {
+            final float blockDelaySeconds = buffer.readFloat();
+            final float disableCooldownScale = buffer.readFloat();
+            final DamageReduction[] damageReductions = DamageReduction.ARRAY_TYPE.read(buffer);
+            final ItemDamageFunction itemDamage = ItemDamageFunction.TYPE.read(buffer);
+            final HolderSet bypassedByTag = Types.OPTIONAL_HOLDER_SET.read(buffer);
+            final Holder<SoundEvent> blockSound = Types.OPTIONAL_SOUND_EVENT.read(buffer);
+            final Holder<SoundEvent> disableSound = Types.OPTIONAL_SOUND_EVENT.read(buffer);
+            return new BlocksAttacks(blockDelaySeconds, disableCooldownScale, damageReductions, itemDamage, bypassedByTag, blockSound, disableSound);
+        }
+
+        @Override
+        public void write(final ByteBuf buffer, final BlocksAttacks value) {
+            buffer.writeFloat(value.blockDelaySeconds());
+            buffer.writeFloat(value.disableCooldownScale());
+            DamageReduction.ARRAY_TYPE.write(buffer, value.damageReductions());
+            ItemDamageFunction.TYPE.write(buffer, value.itemDamage());
+            Types.OPTIONAL_HOLDER_SET.write(buffer, value.bypassedBy());
+            Types.OPTIONAL_SOUND_EVENT.write(buffer, value.blockSound());
+            Types.OPTIONAL_SOUND_EVENT.write(buffer, value.disableSound());
+        }
+
+        @Override
+        public void write(final Ops ops, final BlocksAttacks value) {
+            final DamageReduction[] defaultDamageReductions = {new DamageReduction(90, null, 0, 1)};
+            final ItemDamageFunction defaultItemDamage = new ItemDamageFunction(1, 0, 1);
+            ops.writeMap(map -> map
+                .writeOptional("block_delay_seconds", Types.FLOAT, value.blockDelaySeconds(), 0F)
+                .writeOptional("disable_cooldown_scale", Types.FLOAT, value.disableCooldownScale(), 1F)
+                .writeOptional("damage_reductions", DamageReduction.ARRAY_TYPE, value.damageReductions(), defaultDamageReductions)
+                .writeOptional("item_damage", ItemDamageFunction.TYPE, value.itemDamage(), defaultItemDamage)
+                .writeOptional("bypassed_by", Types.HOLDER_SET, value.bypassedBy())
                .writeOptional("block_sound", Types.SOUND_EVENT, value.blockSound())
                .writeOptional("disabled_sound", Types.SOUND_EVENT, value.disableSound()));
        }
@@ -92,7 +132,7 @@ public record BlocksAttacks(
    public BlocksAttacks rewrite(final UserConnection connection, final Protocol<?, ?, ?, ?> protocol, final boolean clientbound) {
        final Holder<SoundEvent> blockSound = SoundEvent.rewriteHolder(this.blockSound, Rewritable.soundRewriteFunction(protocol, clientbound));
        final Holder<SoundEvent> disableSound = SoundEvent.rewriteHolder(this.disableSound, Rewritable.soundRewriteFunction(protocol, clientbound));
-        return new BlocksAttacks(this.blockDelaySeconds, this.disableCooldownScale, this.damageReductions, this.itemDamage, this.bypassedByTag, blockSound, disableSound);
+        return new BlocksAttacks(this.blockDelaySeconds, this.disableCooldownScale, this.damageReductions, this.itemDamage, this.bypassedBy, blockSound, disableSound);
    }

    public record DamageReduction(float horizontalBlockingAngle, @Nullable HolderSet type, float base, float factor) {
@@ -44,7 +44,7 @@ public final class ContainterContents {
            ops.writeList(list -> {
                for (int i = 0; i < value.length; i++) {
                    final Item item = value[i];
-                    if (item.isEmpty()) {
+                    if (item == null || item.isEmpty()) {
                        continue;
                    }

@@ -28,12 +28,12 @@ import com.viaversion.viaversion.api.type.Type;
 import com.viaversion.viaversion.api.type.Types;
 import com.viaversion.viaversion.util.Key;

-public record DamageResistant(Key typesTagKey) {
+public record DamageResistant1_21_2(Key typesTagKey) {

-    public static final Type<DamageResistant> TYPE = new TransformingType<>(Types.IDENTIFIER, DamageResistant.class, DamageResistant::new, DamageResistant::typesTagKey) {
+    public static final Type<DamageResistant1_21_2> TYPE = new TransformingType<>(Types.IDENTIFIER, DamageResistant1_21_2.class, DamageResistant1_21_2::new, DamageResistant1_21_2::typesTagKey) {

        @Override
-        public void write(final Ops ops, final DamageResistant value) {
+        public void write(final Ops ops, final DamageResistant1_21_2 value) {
            ops.writeMap(map -> map.write("types", Types.TAG_KEY, value.typesTagKey));
        }
    };
@@ -0,0 +1,40 @@
+/*
+ * This file is part of ViaVersion - https://github.com/ViaVersion/ViaVersion
+ * Copyright (C) 2016-2026 ViaVersion and contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+package com.viaversion.viaversion.api.minecraft.item.data;
+
+import com.viaversion.viaversion.api.minecraft.HolderSet;
+import com.viaversion.viaversion.api.minecraft.codec.Ops;
+import com.viaversion.viaversion.api.type.TransformingType;
+import com.viaversion.viaversion.api.type.Type;
+import com.viaversion.viaversion.api.type.Types;
+
+public record DamageResistant26_1(HolderSet types) {
+
+    public static final Type<DamageResistant26_1> TYPE = new TransformingType<>(Types.HOLDER_SET, DamageResistant26_1.class, DamageResistant26_1::new, DamageResistant26_1::types) {
+
+        @Override
+        public void write(final Ops ops, final DamageResistant26_1 value) {
+            ops.writeMap(map -> map.write("types", Types.HOLDER_SET, value.types));
+        }
+    };
+}
@@ -28,7 +28,12 @@ import com.viaversion.viaversion.api.type.Types;
 import com.viaversion.viaversion.api.type.types.EitherType;
 import com.viaversion.viaversion.util.Either;

+/**
+ * 1.21.11-only damage type.
+ *
+ * @param id registry int or string id
+ */
 public record DamageType(Either<Integer, String> id) {

-    public static final Type<DamageType> TYPE = TransformingType.of(new EitherType<>(Types.VAR_INT, Types.STRING), DamageType.class, DamageType::new, DamageType::id);
+    public static final Type<DamageType> TYPE1_21_11 = TransformingType.of(new EitherType<>(Types.VAR_INT, Types.STRING), DamageType.class, DamageType::new, DamageType::id);
 }
@@ -0,0 +1,34 @@
+/*
+ * This file is part of ViaVersion - https://github.com/ViaVersion/ViaVersion
+ * Copyright (C) 2016-2026 ViaVersion and contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+package com.viaversion.viaversion.api.minecraft.item.data;
+
+import com.viaversion.viaversion.api.minecraft.HolderSet;
+import com.viaversion.viaversion.api.minecraft.RegistryKey;
+import com.viaversion.viaversion.api.type.TransformingType;
+import com.viaversion.viaversion.api.type.Type;
+import com.viaversion.viaversion.api.type.types.misc.HolderSetType;
+
+public record ProvidesBannerPatterns(HolderSet patterns) {
+
+    public static final Type<ProvidesBannerPatterns> TYPE = TransformingType.of(new HolderSetType(RegistryKey.of("banner_pattern")), ProvidesBannerPatterns.class, ProvidesBannerPatterns::new, ProvidesBannerPatterns::patterns);
+}
@@ -165,6 +165,30 @@ public interface ViaPlatform<T> {
        return false;
    }

+    /**
+     * Modify the player details payload before it is sent.
+     * This method allows adding, changing, or removing fields from the payload.
+     * It is only called if {@link ViaVersionConfig#sendPlayerDetails()} is true.
+     *
+     * @param connection The UserConnection
+     * @param payload    The constructed payload to modify
+     */
+    default void modifyPlayerDetails(UserConnection connection, JsonObject payload) {
+        // To be overridden if needed
+    }
+
+    /**
+     * Modify the server details payload before it is sent.
+     * This method allows adding, changing, or removing fields from the payload.
+     * It is only called if {@link ViaVersionConfig#sendServerDetails()} is true.
+     *
+     * @param connection The UserConnection
+     * @param payload    The constructed payload to modify
+     */
+    default void modifyServerDetails(UserConnection connection, JsonObject payload) {
+        // To be overridden if needed
+    }
+
    /**
     * Send a custom payload to from a player to the server.
     *
@@ -68,10 +68,6 @@ public interface Protocol<CU extends ClientboundPacketType, CM extends Clientbou
        registerServerbound(state, packetType.getId(), packetType.getId(), handler, false);
    }

-    default void registerServerbound(State state, int unmappedPacketId, int mappedPacketId, @Nullable PacketHandler handler) {
-        registerServerbound(state, unmappedPacketId, mappedPacketId, handler, false);
-    }
-
    /**
     * Registers a serverbound packet, with id transformation and remapper.
     *
@@ -79,19 +75,17 @@ public interface Protocol<CU extends ClientboundPacketType, CM extends Clientbou
     * @param unmappedPacketId unmapped packet id
     * @param mappedPacketId   mapped packet id
     * @param handler          packet handler
-     * @param override         whether an existing mapper should be overridden
     * @see #registerServerbound(ServerboundPacketType, ServerboundPacketType, PacketHandler, boolean)
     */
+    default void registerServerbound(State state, int unmappedPacketId, int mappedPacketId, @Nullable PacketHandler handler) {
+        registerServerbound(state, unmappedPacketId, mappedPacketId, handler, false);
+    }
+
+    @Deprecated(forRemoval = true)
    void registerServerbound(State state, int unmappedPacketId, int mappedPacketId, @Nullable PacketHandler handler, boolean override);

    void cancelServerbound(State state, int mappedPacketId);

-    default void registerClientbound(State state, int unmappedPacketId, int mappedPacketId, @Nullable PacketHandler handler) {
-        registerClientbound(state, unmappedPacketId, mappedPacketId, handler, false);
-    }
-
-    void cancelClientbound(State state, int unmappedPacketId);
-
    /**
     * Registers a clientbound packet, with id transformation and remapper.
     *
@@ -99,9 +93,15 @@ public interface Protocol<CU extends ClientboundPacketType, CM extends Clientbou
     * @param unmappedPacketId unmapped packet id
     * @param mappedPacketId   mapped packet id
     * @param handler          packet handler
-     * @param override         whether an existing mapper should be overridden
     * @see #registerClientbound(ClientboundPacketType, ClientboundPacketType, PacketHandler, boolean)
     */
+    default void registerClientbound(State state, int unmappedPacketId, int mappedPacketId, @Nullable PacketHandler handler) {
+        registerClientbound(state, unmappedPacketId, mappedPacketId, handler, false);
+    }
+
+    void cancelClientbound(State state, int unmappedPacketId);
+
+    @Deprecated(forRemoval = true)
    void registerClientbound(State state, int unmappedPacketId, int mappedPacketId, @Nullable PacketHandler handler, boolean override);

    // ---------------------------------------------------------------------------------------
@@ -144,6 +144,7 @@ public interface Protocol<CU extends ClientboundPacketType, CM extends Clientbou
     * @param handler          packet handler
     * @param override         whether an existing mapping should be overridden if present
     */
+    @Deprecated(forRemoval = true)
    void registerClientbound(CU packetType, @Nullable CM mappedPacketType, @Nullable PacketHandler handler, boolean override);

    /**
@@ -191,6 +192,7 @@ public interface Protocol<CU extends ClientboundPacketType, CM extends Clientbou
     * @param handler          packet handler
     * @param override         whether an existing mapping should be overridden if present
     */
+    @Deprecated(forRemoval = true)
    void registerServerbound(SU packetType, @Nullable SM mappedPacketType, @Nullable PacketHandler handler, boolean override);

    /**
@@ -260,6 +262,22 @@ public interface Protocol<CU extends ClientboundPacketType, CM extends Clientbou
     */
    void appendServerbound(SU type, PacketHandler handler);

+    /**
+     * Replaces a clientbound packet type handler with another.
+     *
+     * @param type    clientbound packet type
+     * @param handler packet handler
+     */
+    void replaceClientbound(CU type, @Nullable PacketHandler handler);
+
+    /**
+     * Replaces a serverbound packet type handler with another.
+     *
+     * @param type    serverbound packet type
+     * @param handler packet handler
+     */
+    void replaceServerbound(SU type, @Nullable PacketHandler handler);
+
    /**
     * Transform a packet using this protocol
     *
@@ -441,4 +459,13 @@ public interface Protocol<CU extends ClientboundPacketType, CM extends Clientbou
    default boolean isBaseProtocol() {
        return false;
    }
+
+    /**
+     * Marks this protocol as dependent on another. Before being initialized, it will wait for the dependency's completion.
+     *
+     * @return protocol class to depend on
+     */
+    default @Nullable Class<? extends Protocol<?, ?, ?, ?>> dependsOn() {
+        return null;
+    }
 }
@@ -249,7 +249,17 @@ public interface ProtocolManager {
     *
     * @return true if the executor has now been shut down
     */
-    boolean checkForMappingCompletion();
+    default boolean checkForMappingCompletion() {
+        return checkForMappingCompletion(false);
+    }
+
+    /**
+     * Shuts down the executor and uncaches mappings if all futures have been completed.
+     *
+     * @param propagateErrors whether to propagate errors from the futures to the caller
+     * @return true if the executor has now been shut down
+     */
+    boolean checkForMappingCompletion(boolean propagateErrors);

    /**
     * Executes the given runnable asynchronously, adding a {@link CompletableFuture}
@@ -328,6 +328,13 @@ public interface PacketWrapper {
     */
    void resetReader();

+    /**
+     * Rewind the reader by the given number of arguments, so they can be read again.
+     *
+     * @param values number of values to add to the reader dequeue again
+     */
+    void rewindReader(int values);
+
    /**
     * Sends this packet to the server.
     * <b>Unlike {@link #sendToServer(Class)}, this method does not handle the pipeline with packet id and data changes.</b>
@@ -382,12 +389,21 @@ public interface PacketWrapper {
     */
    void scheduleSendToServer(Class<? extends Protocol> protocol, boolean skipCurrentPipeline) throws InformativeException;

+    /**
+     * Allows running through code that may both read and write data to/from this packet wrapper,
+     * but will no-op any write call.
+     *
+     * @param runnable runnable to do further method calls on this packet wrapper
+     */
+    void consumeReadsOnly(Runnable runnable);
+
    /**
     * Returns the packet type, or null if not transformed or manually unset.
     *
     * @return packet type if set
     */
-    @Nullable PacketType getPacketType();
+    @Nullable
+    PacketType getPacketType();

    /**
     * Sets the packet type. If set to null, it will not be written to the buffer with {@link #writeToBuffer(ByteBuf)}.
@@ -50,6 +50,11 @@ final class PacketIdMapping implements PacketMapping {
        }
    }

+    @Override
+    public void setHandler(@Nullable final PacketHandler handler) {
+        this.handler = handler;
+    }
+
    @Override
    public @Nullable PacketHandler handler() {
        return handler;
@@ -39,6 +39,13 @@ public interface PacketMapping {
     */
    void applyType(PacketWrapper wrapper);

+    /**
+     * Replaces the current packet handler.
+     *
+     * @param handler packet transformer
+     */
+    void setHandler(@Nullable PacketHandler handler);
+
    /**
     * Returns a packet transformer to transform a packet from one protocol version to another.
     *
@@ -52,6 +52,11 @@ final class PacketTypeMapping implements PacketMapping {
        }
    }

+    @Override
+    public void setHandler(@Nullable final PacketHandler handler) {
+        this.handler = handler;
+    }
+
    @Override
    public @Nullable PacketHandler handler() {
        return handler;
@@ -93,6 +93,7 @@ public class ProtocolVersion implements Comparable<ProtocolVersion> {
    public static final ProtocolVersion v1_21_7 = register(772, "1.21.7-1.21.8", new SubVersionRange("1.21", 7, 8));
    public static final ProtocolVersion v1_21_9 = register(773, "1.21.9-1.21.10", new SubVersionRange("1.21", 9, 10));
    public static final ProtocolVersion v1_21_11 = register(774, "1.21.11");
+    public static final ProtocolVersion v26_1 = register(775, "26.1-26.1.2", new SubVersionRange("26.1", 0, 2));
    public static final ProtocolVersion unknown = new ProtocolVersion(VersionType.SPECIAL, -1, -1, "UNKNOWN", null);

    static {
@@ -26,6 +26,7 @@ import com.google.gson.JsonElement;
 import com.viaversion.nbt.tag.CompoundTag;
 import com.viaversion.nbt.tag.Tag;
 import com.viaversion.viaversion.api.connection.UserConnection;
+import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
 import org.checkerframework.checker.nullness.qual.Nullable;

 public interface ComponentRewriter {
@@ -37,4 +38,6 @@ public interface ComponentRewriter {
    JsonElement processText(UserConnection connection, @Nullable String json);

    void handleShowItem(UserConnection connection, CompoundTag itemTag);
+
+    void passthroughAndProcess(PacketWrapper wrapper);
 }
@@ -28,6 +28,7 @@ import com.viaversion.viaversion.api.minecraft.entities.EntityType;
 import com.viaversion.viaversion.api.minecraft.entitydata.EntityData;
 import com.viaversion.viaversion.api.protocol.Protocol;
 import java.util.List;
+import org.checkerframework.checker.nullness.qual.Nullable;

 public interface EntityRewriter<T extends Protocol<?, ?, ?, ?>> extends Rewriter<T> {

@@ -39,6 +40,8 @@ public interface EntityRewriter<T extends Protocol<?, ?, ?, ?>> extends Rewriter
     */
    EntityType typeFromId(int type);

+    @Nullable EntityType typeFromId(String type);
+
    /**
     * Returns the entity type from the given id.
     * From 1.14 and onwards, this is the same exact value as {@link #typeFromId(int)}.
@@ -70,9 +73,9 @@ public interface EntityRewriter<T extends Protocol<?, ?, ?, ?>> extends Rewriter
    /**
     * Handles and transforms entity data of an entity.
     *
-     * @param entityId     entity id
-     * @param dataList full, mutable list of entity data
-     * @param connection   user connection
+     * @param entityId   entity id
+     * @param dataList   full, mutable list of entity data
+     * @param connection user connection
     */
    void handleEntityData(int entityId, List<EntityData> dataList, UserConnection connection);

@@ -102,6 +102,16 @@ public interface ItemRewriter<T extends Protocol<?, ?, ?, ?>> extends Rewriter<T
        return itemArrayType();
    }

+    @Nullable
+    default Type<Item> itemTemplateType() {
+        return itemType();
+    }
+
+    @Nullable
+    default Type<Item> mappedItemTemplateType() {
+        return mappedItemType();
+    }
+
    /**
     * Returns the NBT tag name used for storing original item data.
     *
@@ -22,10 +22,22 @@
 */
 package com.viaversion.viaversion.api.rewriter;

+import com.viaversion.nbt.tag.CompoundTag;
+import com.viaversion.viaversion.api.connection.UserConnection;
+import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
 import com.viaversion.viaversion.util.KeyMappings;
 import org.checkerframework.checker.nullness.qual.Nullable;

 public interface RegistryDataRewriter {

-    @Nullable KeyMappings getMappings(String registryKey);
+    void handle(PacketWrapper wrapper);
+
+    @Nullable
+    KeyMappings getMappings(String registryKey);
+
+    boolean shouldRemoveRegistry(String registryKey);
+
+    boolean hasRegistriesToRemove();
+
+    void updateDialog(UserConnection connection, CompoundTag tag);
 }
@@ -103,10 +103,11 @@ import com.viaversion.viaversion.api.type.types.math.BlockPositionType1_8;
 import com.viaversion.viaversion.api.type.types.math.ChunkPositionType;
 import com.viaversion.viaversion.api.type.types.math.EulerAngleType;
 import com.viaversion.viaversion.api.type.types.math.GlobalBlockPositionType;
-import com.viaversion.viaversion.api.type.types.math.MovementVectorType;
+import com.viaversion.viaversion.api.type.types.math.LowPrecisionVectorType;
 import com.viaversion.viaversion.api.type.types.math.QuaternionType;
 import com.viaversion.viaversion.api.type.types.math.Vector3fType;
 import com.viaversion.viaversion.api.type.types.math.VectorType;
+import com.viaversion.viaversion.api.type.types.misc.CompoundTagHolderType;
 import com.viaversion.viaversion.api.type.types.misc.CompoundTagType;
 import com.viaversion.viaversion.api.type.types.misc.GameProfileType;
 import com.viaversion.viaversion.api.type.types.misc.HolderSetType;
@@ -198,13 +199,16 @@ public final class Types {
    public static final Type<Vector> VECTOR = new VectorType();
    public static final Type<Vector3f> VECTOR3F = new Vector3fType();
    public static final Type<Quaternion> QUATERNION = new QuaternionType();
-    public static final Type<Vector3d> MOVEMENT_VECTOR = new MovementVectorType();
+    public static final Type<Vector3d> LOW_PRECISION_VECTOR = new LowPrecisionVectorType();
+    @Deprecated(forRemoval = true)
+    public static final Type<Vector3d> MOVEMENT_VECTOR = LOW_PRECISION_VECTOR;

    public static final Type<CompoundTag> NAMED_COMPOUND_TAG = new NamedCompoundTagType();
    public static final Type<CompoundTag> OPTIONAL_NAMED_COMPOUND_TAG = new NamedCompoundTagType.OptionalNamedCompoundTagType();
    public static final Type<CompoundTag[]> NAMED_COMPOUND_TAG_ARRAY = new ArrayType<>(Types.NAMED_COMPOUND_TAG);
    public static final Type<CompoundTag> COMPOUND_TAG = new CompoundTagType();
    public static final Type<CompoundTag> OPTIONAL_COMPOUND_TAG = CompoundTagType.OptionalCompoundTagType.type();
+    public static final HolderType<CompoundTag> TRUSTED_COMPOUND_TAG_HOLDER = new CompoundTagHolderType();

    public static final Type<Tag> TAG = new TagType();
    public static final Type<Tag[]> TAG_ARRAY = new ArrayType<>(TAG);
@@ -28,13 +28,21 @@ import com.viaversion.viaversion.api.type.Types;
 import io.netty.buffer.ByteBuf;

 public class VarIntArrayType extends Type<int[]> {
-    public VarIntArrayType() {
+
+    private final int length;
+
+    public VarIntArrayType(final int length) {
        super(int[].class);
+        this.length = length;
+    }
+
+    public VarIntArrayType() {
+        this(-1);
    }

    @Override
    public int[] read(ByteBuf buffer) {
-        int length = Types.VAR_INT.readPrimitive(buffer);
+        int length = this.length == -1 ? Types.VAR_INT.readPrimitive(buffer) : this.length;
        Preconditions.checkArgument(buffer.isReadable(length)); // Sanity check, at least 1 byte will be used for each varint
        int[] array = new int[length];
        for (int i = 0; i < array.length; i++) {
@@ -45,7 +53,11 @@ public class VarIntArrayType extends Type<int[]> {

    @Override
    public void write(ByteBuf buffer, int[] object) {
-        Types.VAR_INT.writePrimitive(buffer, object.length);
+        if (this.length != -1) {
+            Preconditions.checkArgument(length == object.length, "Length does not match expected length");
+        } else {
+            Types.VAR_INT.writePrimitive(buffer, object.length);
+        }
        for (int i : object) {
            Types.VAR_INT.writePrimitive(buffer, i);
        }
@@ -40,7 +40,7 @@ public class BlockEntityType1_20_2 extends Type<BlockEntity> {
        final byte xz = buffer.readByte();
        final short y = buffer.readShort();
        final int typeId = Types.VAR_INT.readPrimitive(buffer);
-        final CompoundTag tag = Types.COMPOUND_TAG.read(buffer);
+        final CompoundTag tag = Types.TRUSTED_COMPOUND_TAG.read(buffer);
        return new BlockEntityImpl(xz, y, typeId, tag);
    }

@@ -49,6 +49,6 @@ public class BlockEntityType1_20_2 extends Type<BlockEntity> {
        buffer.writeByte(entity.packedXZ());
        buffer.writeShort(entity.y());
        Types.VAR_INT.writePrimitive(buffer, entity.typeId());
-        Types.COMPOUND_TAG.write(buffer, entity.tag());
+        Types.TRUSTED_COMPOUND_TAG.write(buffer, entity.tag());
    }
 }
@@ -31,8 +31,8 @@ import io.netty.buffer.ByteBuf;

 public class ChunkSectionType1_18 extends Type<ChunkSection> {

-    private final PaletteTypeBase blockPaletteType;
-    private final PaletteTypeBase biomePaletteType;
+    protected final PaletteTypeBase blockPaletteType;
+    protected final PaletteTypeBase biomePaletteType;

    public ChunkSectionType1_18(final int globalPaletteBlockBits, final int globalPaletteBiomeBits) {
        super(ChunkSection.class);
@@ -0,0 +1,68 @@
+/*
+ * This file is part of ViaVersion - https://github.com/ViaVersion/ViaVersion
+ * Copyright (C) 2016-2026 ViaVersion and contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+package com.viaversion.viaversion.api.type.types.chunk;
+
+import com.viaversion.viaversion.api.minecraft.chunks.Chunk;
+import com.viaversion.viaversion.api.minecraft.chunks.ChunkSection;
+import com.viaversion.viaversion.api.minecraft.chunks.ChunkSectionImpl;
+import com.viaversion.viaversion.api.minecraft.chunks.PaletteType;
+import io.netty.buffer.ByteBuf;
+
+public class ChunkSectionType26_1 extends ChunkSectionType1_18 {
+
+    public ChunkSectionType26_1(final int globalPaletteBlockBits, final int globalPaletteBiomeBits) {
+        super(
+            new PaletteType1_21_5(PaletteType.BLOCKS, globalPaletteBlockBits),
+            new PaletteType1_21_5(PaletteType.BIOMES, globalPaletteBiomeBits)
+        );
+    }
+
+    @Override
+    public ChunkSection read(final ByteBuf buffer) {
+        final ChunkSection chunkSection = new ChunkSectionImpl();
+        chunkSection.setNonAirBlocksCount(buffer.readShort());
+        chunkSection.setFluidCount(buffer.readShort());
+        chunkSection.addPalette(PaletteType.BLOCKS, blockPaletteType.read(buffer));
+        chunkSection.addPalette(PaletteType.BIOMES, biomePaletteType.read(buffer));
+        return chunkSection;
+    }
+
+    @Override
+    public void write(final ByteBuf buffer, final ChunkSection section) {
+        buffer.writeShort(section.getNonAirBlocksCount());
+        buffer.writeShort(section.getFluidCount());
+        blockPaletteType.write(buffer, section.palette(PaletteType.BLOCKS));
+        biomePaletteType.write(buffer, section.palette(PaletteType.BIOMES));
+    }
+
+    @Override
+    public int serializedSize(final Chunk chunk) {
+        int length = 0;
+        for (final ChunkSection section : chunk.getSections()) {
+            length += Short.BYTES + Short.BYTES // non-air and fluid count
+                + blockPaletteType.serializedSize(section.palette(PaletteType.BLOCKS))
+                + biomePaletteType.serializedSize(section.palette(PaletteType.BIOMES));
+        }
+        return length;
+    }
+}
@@ -34,14 +34,18 @@ import io.netty.buffer.ByteBuf;
 import java.util.ArrayList;
 import java.util.List;

-public final class ChunkType1_21_5 extends Type<Chunk> {
+public class ChunkType1_21_5 extends Type<Chunk> {
    private final ChunkSectionType1_18 sectionType;
    private final int ySectionCount;

    public ChunkType1_21_5(final int ySectionCount, final int globalPaletteBlockBits, final int globalPaletteBiomeBits) {
+        this(new ChunkSectionType1_21_5(globalPaletteBlockBits, globalPaletteBiomeBits), ySectionCount);
+    }
+
+    protected ChunkType1_21_5(final ChunkSectionType1_18 sectionType, final int ySectionCount) {
        super(Chunk.class);
        Preconditions.checkArgument(ySectionCount > 0);
-        this.sectionType = new ChunkSectionType1_21_5(globalPaletteBlockBits, globalPaletteBiomeBits);
+        this.sectionType = sectionType;
        this.ySectionCount = ySectionCount;
    }

@@ -20,17 +20,11 @@
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
-package com.viaversion.viaversion.api.protocol;
+package com.viaversion.viaversion.api.type.types.chunk;

-/**
- * A simple protocol which does not have any packet types.
- * <p>
- * {@link AbstractProtocol} should be preferred over this class in most cases.
- */
-public abstract class AbstractSimpleProtocol extends AbstractProtocol<SimpleProtocol.DummyPacketTypes, SimpleProtocol.DummyPacketTypes,
-    SimpleProtocol.DummyPacketTypes, SimpleProtocol.DummyPacketTypes> implements SimpleProtocol {
+public final class ChunkType26_1 extends ChunkType1_21_5 {

-    protected AbstractSimpleProtocol() {
-        super(null, null, null, null);
+    public ChunkType26_1(final int ySectionCount, final int globalPaletteBlockBits, final int globalPaletteBiomeBits) {
+        super(new ChunkSectionType26_1(globalPaletteBlockBits, globalPaletteBiomeBits), ySectionCount);
    }
 }
@@ -0,0 +1,64 @@
+/*
+ * This file is part of ViaVersion - https://github.com/ViaVersion/ViaVersion
+ * Copyright (C) 2016-2026 ViaVersion and contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+package com.viaversion.viaversion.api.type.types.item;
+
+import com.viaversion.viaversion.api.minecraft.data.StructuredData;
+import com.viaversion.viaversion.api.minecraft.data.StructuredDataContainer;
+import com.viaversion.viaversion.api.minecraft.data.StructuredDataKey;
+import com.viaversion.viaversion.api.minecraft.item.Item;
+import com.viaversion.viaversion.api.minecraft.item.StructuredItemTemplate;
+import com.viaversion.viaversion.api.type.OptionalType;
+import com.viaversion.viaversion.api.type.Type;
+import com.viaversion.viaversion.api.type.Types;
+import io.netty.buffer.ByteBuf;
+import java.util.Map;
+
+// Holds the same exact data as a regular item stack
+public class ItemTemplateType26_1 extends ItemType1_20_5 {
+
+    public ItemTemplateType26_1(final StructuredDataTypeBase dataType) {
+        super(dataType);
+    }
+
+    @Override
+    public Item read(final ByteBuf buffer) {
+        final int id = Types.VAR_INT.readPrimitive(buffer);
+        final int amount = Types.VAR_INT.readPrimitive(buffer);
+        final Map<StructuredDataKey<?>, StructuredData<?>> data = readData(buffer);
+        return new StructuredItemTemplate(id, amount, new StructuredDataContainer(data));
+    }
+
+    @Override
+    public void write(final ByteBuf buffer, final Item object) {
+        Types.VAR_INT.writePrimitive(buffer, object.identifier());
+        Types.VAR_INT.writePrimitive(buffer, object.amount());
+        writeData(buffer, object);
+    }
+
+    public static final class OptionalItemTemplateType extends OptionalType<Item> {
+
+        public OptionalItemTemplateType(final Type<Item> type) {
+            super(type);
+        }
+    }
+}
@@ -58,7 +58,7 @@ public class ItemType1_20_5 extends Type<Item> {
        return new StructuredItem(id, amount, new StructuredDataContainer(data));
    }

-    private Map<StructuredDataKey<?>, StructuredData<?>> readData(final ByteBuf buffer) {
+    protected Map<StructuredDataKey<?>, StructuredData<?>> readData(final ByteBuf buffer) {
        final int valuesSize = Types.VAR_INT.readPrimitive(buffer);
        final int markersSize = Types.VAR_INT.readPrimitive(buffer);
        if (valuesSize == 0 && markersSize == 0) {
@@ -92,6 +92,10 @@ public class ItemType1_20_5 extends Type<Item> {
        Types.VAR_INT.writePrimitive(buffer, object.amount());
        Types.VAR_INT.writePrimitive(buffer, object.identifier());

+        writeData(buffer, object);
+    }
+
+    protected void writeData(final ByteBuf buffer, final Item object) {
        final Map<StructuredDataKey<?>, StructuredData<?>> data = object.dataContainer().data();
        int valuesSize = 0;
        int markersSize = 0;
@@ -29,7 +29,7 @@ import com.viaversion.viaversion.api.type.types.UnsignedIntType;
 import com.viaversion.viaversion.util.MathUtil;
 import io.netty.buffer.ByteBuf;

-public class MovementVectorType extends Type<Vector3d> {
+public class LowPrecisionVectorType extends Type<Vector3d> {
    // Using 15 bits, steal short constants for it
    private static final double MAX_QUANTIZED_VALUE = Short.MAX_VALUE - 1;
    private static final int SCALE_BITS = 2; // first 2 bits for the scale
@@ -38,7 +38,7 @@ public class MovementVectorType extends Type<Vector3d> {
    private static final double ABS_MAX_VALUE = (1L << Integer.SIZE + SCALE_BITS) - 1; // Unsigned int + the first two scale bits
    private static final double ABS_MIN_VALUE = 1 / MAX_QUANTIZED_VALUE;

-    public MovementVectorType() {
+    public LowPrecisionVectorType() {
        super(Vector3d.class);
    }

@@ -0,0 +1,40 @@
+/*
+ * This file is part of ViaVersion - https://github.com/ViaVersion/ViaVersion
+ * Copyright (C) 2016-2026 ViaVersion and contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+package com.viaversion.viaversion.api.type.types.misc;
+
+import com.viaversion.nbt.tag.CompoundTag;
+import com.viaversion.viaversion.api.type.Types;
+import io.netty.buffer.ByteBuf;
+
+public final class CompoundTagHolderType extends HolderType<CompoundTag> {
+
+    @Override
+    public CompoundTag readDirect(final ByteBuf buffer) {
+        return Types.TRUSTED_COMPOUND_TAG.read(buffer);
+    }
+
+    @Override
+    public void writeDirect(final ByteBuf buffer, final CompoundTag value) {
+        Types.TRUSTED_COMPOUND_TAG.write(buffer, value);
+    }
+}
@@ -29,6 +29,11 @@ import com.viaversion.viaversion.api.type.Types;
 import com.viaversion.viaversion.util.Key;
 import io.netty.buffer.ByteBuf;

+/**
+ * Mess for certain pre 26.1 things.
+ *
+ * @param <T> held type
+ */
 public final class EitherHolderType<T> extends Type<EitherHolder<T>> {
    private final HolderType<T> holderType;

@@ -30,6 +30,7 @@ import com.viaversion.viaversion.api.minecraft.codec.Ops;
 import com.viaversion.viaversion.api.type.OptionalType;
 import com.viaversion.viaversion.api.type.Type;
 import com.viaversion.viaversion.api.type.Types;
+import com.viaversion.viaversion.api.type.types.VarIntArrayType;
 import com.viaversion.viaversion.util.Key;
 import io.netty.buffer.ByteBuf;

@@ -58,12 +59,7 @@ public class HolderSetType extends Type<HolderSet> {
            final String tag = Types.STRING.read(buffer);
            return HolderSet.of(tag);
        }
-
-        final int[] values = new int[size];
-        for (int i = 0; i < size; i++) {
-            values[i] = Types.VAR_INT.readPrimitive(buffer);
-        }
-        return HolderSet.of(values);
+        return HolderSet.of(new VarIntArrayType(size).read(buffer));
    }

    @Override
@@ -59,17 +59,13 @@ public class ParticleType extends DynamicType<Particle> {
        return protocol.getMappingData().getParticleMappings();
    }

-    public static DataReader<Particle> itemHandler(final Type<Item> itemType) {
-        return (buf, particle) -> particle.add(itemType, itemType.read(buf));
-    }
-
    public static final class Readers {

        public static final DataReader<Particle> BLOCK = (buf, particle) -> {
            particle.add(Types.VAR_INT, Types.VAR_INT.readPrimitive(buf)); // Flat Block
        };
-        public static final DataReader<Particle> ITEM1_13 = itemHandler(Types.ITEM1_13);
-        public static final DataReader<Particle> ITEM1_13_2 = itemHandler(Types.ITEM1_13_2);
+        public static final DataReader<Particle> ITEM1_13 = item(Types.ITEM1_13);
+        public static final DataReader<Particle> ITEM1_13_2 = item(Types.ITEM1_13_2);
        public static final DataReader<Particle> DUST = (buf, particle) -> {
            particle.add(Types.FLOAT, Types.FLOAT.readPrimitive(buf)); // Red 0-1
            particle.add(Types.FLOAT, Types.FLOAT.readPrimitive(buf)); // Green 0-1
@@ -172,4 +168,103 @@ public class ParticleType extends DynamicType<Particle> {
            return (buf, particle) -> particle.add(item, item.read(buf));
        }
    }
+
+    public static final class Fillers {
+
+        public static DynamicType<Particle>.DataFiller fill1_13_2(final Protocol<?, ?, ?, ?> protocol, final ParticleType type, final boolean useMappedNames) {
+            return type.filler(protocol, useMappedNames)
+                .reader("item", Readers.item(protocol.getItemRewriter().mappedItemType()))
+                .reader("block", Readers.BLOCK)
+                .reader("dust", Readers.DUST)
+                .reader("falling_dust", Readers.BLOCK);
+        }
+
+        public static DataFiller fill1_17(final Protocol<?, ?, ?, ?> protocol, final ParticleType type) {
+            return fill1_13_2(protocol, type, true)
+                .reader("dust_color_transition", Readers.DUST_TRANSITION)
+                .reader("vibration", Readers.VIBRATION);
+        }
+
+        public static void fill1_18(final Protocol<?, ?, ?, ?> protocol, final ParticleType type) {
+            fill1_17(protocol, type).reader("block_marker", Readers.BLOCK);
+        }
+
+        public static void fill1_19(final Protocol<?, ?, ?, ?> protocol, final ParticleType type) {
+            type.filler(protocol)
+                .reader("item", Readers.item(protocol.getItemRewriter().mappedItemType()))
+                .reader("block", Readers.BLOCK)
+                .reader("block_marker", Readers.BLOCK)
+                .reader("dust", Readers.DUST)
+                .reader("falling_dust", Readers.BLOCK)
+                .reader("dust_color_transition", Readers.DUST_TRANSITION)
+                .reader("vibration", Readers.VIBRATION1_19)
+                .reader("sculk_charge", Readers.SCULK_CHARGE)
+                .reader("shriek", Readers.SHRIEK);
+        }
+
+        public static DataFiller fill1_20_3(final Protocol<?, ?, ?, ?> protocol, final ParticleType type) {
+            return type.filler(protocol)
+                .reader("item", Readers.item(protocol.getItemRewriter().mappedItemType()))
+                .reader("block", Readers.BLOCK)
+                .reader("block_marker", Readers.BLOCK)
+                .reader("dust", Readers.DUST)
+                .reader("falling_dust", Readers.BLOCK)
+                .reader("dust_color_transition", Readers.DUST_TRANSITION)
+                .reader("vibration", Readers.VIBRATION1_20_3)
+                .reader("sculk_charge", Readers.SCULK_CHARGE)
+                .reader("shriek", Readers.SHRIEK);
+        }
+
+        public static void fill1_20_5(final Protocol<?, ?, ?, ?> protocol, final ParticleType type) {
+            fill1_20_3(protocol, type)
+                .reader("dust_pillar", Readers.BLOCK)
+                .reader("entity_effect", Readers.COLOR);
+        }
+
+        public static void fill1_21_2(final Protocol<?, ?, ?, ?> protocol) {
+            protocol.mappedTypes().particle().filler(protocol)
+                .reader("item", Readers.item(protocol.getItemRewriter().mappedItemType()))
+                .reader("block", Readers.BLOCK)
+                .reader("block_marker", Readers.BLOCK)
+                .reader("dust_pillar", Readers.BLOCK)
+                .reader("falling_dust", Readers.BLOCK)
+                .reader("block_crumble", Readers.BLOCK)
+                .reader("dust", Readers.DUST1_21_2)
+                .reader("dust_color_transition", Readers.DUST_TRANSITION1_21_2)
+                .reader("vibration", Readers.VIBRATION1_20_3)
+                .reader("sculk_charge", Readers.SCULK_CHARGE)
+                .reader("shriek", Readers.SHRIEK)
+                .reader("entity_effect", Readers.COLOR)
+                .reader("trail", Readers.TRAIL1_21_2);
+        }
+
+        public static DataFiller fill1_21_4(final Protocol<?, ?, ?, ?> protocol) {
+            return protocol.mappedTypes().particle().filler(protocol)
+                .reader("item", Readers.item(protocol.getItemRewriter().mappedItemTemplateType()))
+                .reader("block", Readers.BLOCK)
+                .reader("block_marker", Readers.BLOCK)
+                .reader("dust_pillar", Readers.BLOCK)
+                .reader("falling_dust", Readers.BLOCK)
+                .reader("block_crumble", Readers.BLOCK)
+                .reader("dust", Readers.DUST1_21_2)
+                .reader("dust_color_transition", Readers.DUST_TRANSITION1_21_2)
+                .reader("vibration", Readers.VIBRATION1_20_3)
+                .reader("sculk_charge", Readers.SCULK_CHARGE)
+                .reader("shriek", Readers.SHRIEK)
+                .reader("entity_effect", Readers.COLOR)
+                .reader("trail", Readers.TRAIL1_21_4);
+        }
+
+        public static DataFiller fill1_21_5(final Protocol<?, ?, ?, ?> protocol) {
+            return fill1_21_4(protocol).reader("tinted_leaves", Readers.COLOR);
+        }
+
+        public static void fill1_21_9(final Protocol<?, ?, ?, ?> protocol) {
+            fill1_21_5(protocol)
+                .reader("dragon_breath", Readers.POWER)
+                .reader("effect", Readers.SPELL)
+                .reader("instant_effect", Readers.SPELL)
+                .reader("flash", Readers.COLOR);
+        }
+    }
 }
@@ -50,7 +50,7 @@ public class Types1_20_5<K extends VersionedStructuredDataKeys, E extends Abstra
    public final Type<Item[]> itemArray = new ArrayType<>(item);
    public final Type<Item> itemCost = new ItemCostType1_20_5(structuredDataArray);
    public final Type<Item> optionalItemCost = new ItemCostType1_20_5.OptionalItemCostType(itemCost);
-    public final K structuredDataKeys;
+    private K structuredDataKeys;

    public final ParticleType particle = new ParticleType();
    public final ArrayType<Particle> particles = new ArrayType<>(particle);
@@ -58,11 +58,17 @@ public class Types1_20_5<K extends VersionedStructuredDataKeys, E extends Abstra
    public final Type<EntityData> entityData;
    public final Type<List<EntityData>> entityDataList;

-    public Types1_20_5(final Function<Types1_20_5<?, ?>, K> keysSupplier, final Function<Types1_20_5<?, ?>, E> entityDataTypesSupplier) {
-        this.structuredDataKeys = keysSupplier.apply(this);
+    public Types1_20_5(final Function<VersionedTypesHolder, K> keysSupplier, final Function<VersionedTypesHolder, E> entityDataTypesSupplier) {
        this.entityDataTypes = entityDataTypesSupplier.apply(this);
        this.entityData = new EntityDataType(entityDataTypes);
        this.entityDataList = new EntityDataListType(entityData);
+        if (keysSupplier != null) {
+            initKeys(keysSupplier);
+        }
+    }
+
+    protected void initKeys(final Function<VersionedTypesHolder, K> keysSupplier) {
+        this.structuredDataKeys = keysSupplier.apply(this);
    }

    @Override
@@ -75,6 +81,21 @@ public class Types1_20_5<K extends VersionedStructuredDataKeys, E extends Abstra
        return itemArray;
    }

+    @Override
+    public Type<Item> itemTemplate() {
+        return item;
+    }
+
+    @Override
+    public Type<Item> optionalItemTemplate() {
+        return item;
+    }
+
+    @Override
+    public Type<Item[]> itemTemplateArray() {
+        return itemArray;
+    }
+
    @Override
    public Type<Item> itemCost() {
        return itemCost;
@@ -34,7 +34,7 @@ public final class Types1_21 extends Types1_20_5<StructuredDataKeys1_20_5, Entit

    public final Type<Item> optionalItem; // Optional as in boolean prefixed, not via the amount

-    public Types1_21(final Function<Types1_20_5<?, ?>, StructuredDataKeys1_20_5> keysSupplier, final Function<Types1_20_5<?, ?>, EntityDataTypes1_21> entityDataTypesSupplier) {
+    public Types1_21(final Function<VersionedTypesHolder, StructuredDataKeys1_20_5> keysSupplier, final Function<VersionedTypesHolder, EntityDataTypes1_21> entityDataTypesSupplier) {
        super(keysSupplier, entityDataTypesSupplier);
        this.optionalItem = ((ItemType1_20_5) item).new OptionalItemType();
    }
@@ -0,0 +1,58 @@
+/*
+ * This file is part of ViaVersion - https://github.com/ViaVersion/ViaVersion
+ * Copyright (C) 2016-2026 ViaVersion and contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+package com.viaversion.viaversion.api.type.types.version;
+
+import com.viaversion.viaversion.api.minecraft.data.version.VersionedStructuredDataKeys;
+import com.viaversion.viaversion.api.minecraft.entitydata.types.AbstractEntityDataTypes;
+import com.viaversion.viaversion.api.minecraft.item.Item;
+import com.viaversion.viaversion.api.type.Type;
+import com.viaversion.viaversion.api.type.types.ArrayType;
+import com.viaversion.viaversion.api.type.types.item.ItemTemplateType26_1;
+import java.util.function.Function;
+
+public class Types26_1<K extends VersionedStructuredDataKeys, E extends AbstractEntityDataTypes> extends Types1_20_5<K, E> {
+
+    public final Type<Item> itemTemplate = new ItemTemplateType26_1(structuredData);
+    public final Type<Item> optionalItemTemplate = new ItemTemplateType26_1.OptionalItemTemplateType(itemTemplate);
+    public final Type<Item[]> itemTemplateArray = new ArrayType<>(itemTemplate);
+
+    public Types26_1(final Function<VersionedTypesHolder, K> keysSupplier, final Function<VersionedTypesHolder, E> entityDataTypesSupplier) {
+        super(null, entityDataTypesSupplier);
+        initKeys(keysSupplier);
+    }
+
+    @Override
+    public Type<Item> itemTemplate() {
+        return itemTemplate;
+    }
+
+    @Override
+    public Type<Item> optionalItemTemplate() {
+        return optionalItemTemplate;
+    }
+
+    @Override
+    public Type<Item[]> itemTemplateArray() {
+        return itemTemplateArray;
+    }
+}
@@ -32,6 +32,7 @@ import com.viaversion.viaversion.api.minecraft.entitydata.types.EntityDataTypes1
 import com.viaversion.viaversion.api.minecraft.entitydata.types.EntityDataTypes1_21_2;
 import com.viaversion.viaversion.api.minecraft.entitydata.types.EntityDataTypes1_21_5;
 import com.viaversion.viaversion.api.minecraft.entitydata.types.EntityDataTypes1_21_9;
+import com.viaversion.viaversion.api.minecraft.entitydata.types.EntityDataTypes26_1;

 /**
 * Holds versioned accessors for highly volatile types, specifically around items and data components.
@@ -49,4 +50,5 @@ public final class VersionedTypes {
    public static final Types1_20_5<StructuredDataKeys1_21_5, EntityDataTypes1_21_5> V1_21_6 = new Types1_20_5<>(StructuredDataKeys1_21_5::new, EntityDataTypes1_21_5::new);
    public static final Types1_20_5<StructuredDataKeys1_21_5, EntityDataTypes1_21_9> V1_21_9 = new Types1_20_5<>(StructuredDataKeys1_21_5::new, EntityDataTypes1_21_9::new);
    public static final Types1_20_5<StructuredDataKeys1_21_11, EntityDataTypes1_21_11> V1_21_11 = new Types1_20_5<>(StructuredDataKeys1_21_11::new, EntityDataTypes1_21_11::new);
+    public static final Types26_1<StructuredDataKeys1_21_11, EntityDataTypes26_1> V26_1 = new Types26_1<>(StructuredDataKeys1_21_11::new, EntityDataTypes26_1::new);
 }
@@ -39,10 +39,31 @@ import java.util.List;
 */
 public interface VersionedTypesHolder {

+    /**
+     * Returns the unmapped item stack type
+     *
+     * @return unmapped item stack type
+     */
    Type<Item> item();

    Type<Item[]> itemArray();

+    /**
+     * Returns the unmapped item stack template type, used for certain recipes/templates in 26.1+.
+     *
+     * @return unmapped item stack template type
+     */
+    Type<Item> itemTemplate();
+
+    Type<Item> optionalItemTemplate();
+
+    Type<Item[]> itemTemplateArray();
+
+    /**
+     * Returns the unmapped item cost type, used in merchant offers.
+     *
+     * @return unmapped item cost type
+     */
    Type<Item> itemCost();

    Type<Item> optionalItemCost();
@@ -60,7 +60,7 @@ public class InformativeException extends RuntimeException {

    @Override
    public String getMessage() {
-        final StringBuilder builder = new StringBuilder("Please report this on the Via support Discord or open an issue on the relevant GitHub repository\n");
+        final StringBuilder builder = new StringBuilder("Please report the full error (!) from the console on the Via support Discord or open an issue on the relevant GitHub repository.\n");
        boolean first = true;
        for (final DataEntry entry : dataEntries) {
            if (!first) {
@@ -48,7 +48,7 @@ public final class Key {
     * Creates a new key with the given namespace and path.
     *
     * @param namespace the namespace of the identifier
-     * @param path the path of the identifier
+     * @param path      the path of the identifier
     * @return a new key with the given namespace and path
     */
    public static Key of(final String namespace, final String path) {
@@ -8,7 +8,7 @@ repositories {

 dependencies {
    // version must be manually kept in sync with the one in root project settings.gradle.kts
-    implementation("com.gradleup.shadow:shadow-gradle-plugin:9.3.1")
+    implementation("com.gradleup.shadow:shadow-gradle-plugin:9.4.1")

    // A nice no-conflict comment for patching in downgrading
 }
@@ -49,6 +49,20 @@ public final class NMSUtil {
        }
    }

+    public static Class<?> nms(String className, String... fallbackFullClassNames) throws ClassNotFoundException {
+        try {
+            return Class.forName(NMS + "." + className);
+        } catch (ClassNotFoundException ignored) {
+        }
+        for (final String fallbackFullClassName : fallbackFullClassNames) {
+            try {
+                return Class.forName(fallbackFullClassName);
+            } catch (ClassNotFoundException ignored) {
+            }
+        }
+        throw new ClassNotFoundException(className);
+    }
+
    public static Class<?> obc(String className) throws ClassNotFoundException {
        return Class.forName(BASE + "." + className);
    }
@@ -105,7 +105,8 @@ public class BukkitViaInjector extends LegacyViaInjector {
        // Grab the ping class and find the field to access it
        Class<?> pingClazz = NMSUtil.nms(
            "ServerPing",
-            "net.minecraft.network.protocol.status.ServerPing"
+            "net.minecraft.network.protocol.status.ServerPing",
+            "net.minecraft.network.protocol.status.ServerStatus"
        );
        Object ping = null;
        for (Field field : serverClazz.getDeclaredFields()) {
@@ -120,7 +121,8 @@ public class BukkitViaInjector extends LegacyViaInjector {
        // Now get the ServerData inside ServerPing
        Class<?> serverDataClass = NMSUtil.nms(
            "ServerPing$ServerData",
-            "net.minecraft.network.protocol.status.ServerPing$ServerData"
+            "net.minecraft.network.protocol.status.ServerPing$ServerData",
+            "net.minecraft.network.protocol.status.ServerStatus$Version"
        );
        Object serverData = null;
        for (Field field : pingClazz.getDeclaredFields()) {
@@ -155,7 +157,8 @@ public class BukkitViaInjector extends LegacyViaInjector {
        );
        Class<?> connectionClass = NMSUtil.nms(
            "ServerConnection",
-            "net.minecraft.server.network.ServerConnection"
+            "net.minecraft.server.network.ServerConnection",
+            "net.minecraft.server.network.ServerConnectionListener"
        );

        Object server = ReflectionUtil.invokeStatic(serverClass, "getServer");
@@ -2,23 +2,18 @@
 * This file is part of ViaVersion - https://github.com/ViaVersion/ViaVersion
 * Copyright (C) 2016-2026 ViaVersion and contributors
 *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
 *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
 *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 package com.viaversion.viaversion.api.protocol;

@@ -27,6 +22,7 @@ import com.viaversion.viaversion.api.Via;
 import com.viaversion.viaversion.api.connection.UserConnection;
 import com.viaversion.viaversion.api.data.entity.EntityTracker;
 import com.viaversion.viaversion.api.data.item.ItemHasher;
+import com.viaversion.viaversion.api.minecraft.entities.EntityType;
 import com.viaversion.viaversion.api.protocol.packet.ClientboundPacketType;
 import com.viaversion.viaversion.api.protocol.packet.Direction;
 import com.viaversion.viaversion.api.protocol.packet.PacketType;
@@ -39,10 +35,17 @@ import com.viaversion.viaversion.api.protocol.packet.provider.PacketTypeMap;
 import com.viaversion.viaversion.api.protocol.packet.provider.PacketTypesProvider;
 import com.viaversion.viaversion.api.protocol.packet.provider.SimplePacketTypesProvider;
 import com.viaversion.viaversion.api.protocol.remapper.PacketHandler;
+import com.viaversion.viaversion.api.protocol.version.ProtocolVersion;
 import com.viaversion.viaversion.api.rewriter.MappingDataListener;
 import com.viaversion.viaversion.api.rewriter.Rewriter;
+import com.viaversion.viaversion.data.entity.EntityTrackerBase;
+import com.viaversion.viaversion.data.item.ItemHasherBase;
 import com.viaversion.viaversion.exception.CancelException;
 import com.viaversion.viaversion.exception.InformativeException;
+import com.viaversion.viaversion.protocol.shared_registration.SharedRegistrations;
+import com.viaversion.viaversion.rewriter.RecipeDisplayRewriter;
+import com.viaversion.viaversion.rewriter.TagRewriter;
+import com.viaversion.viaversion.rewriter.text.ComponentRewriterBase;
 import com.viaversion.viaversion.util.ProtocolLogger;
 import com.viaversion.viaversion.util.ProtocolUtil;
 import java.util.HashMap;
@@ -74,6 +77,8 @@ public abstract class AbstractProtocol<CU extends ClientboundPacketType, CM exte
    private final Map<Class<?>, Object> storedObjects = new HashMap<>();
    private boolean initialized;
    private ProtocolLogger logger;
+    private ProtocolVersion serverVersion;
+    private ProtocolVersion clientVersion;

    @Deprecated
    protected AbstractProtocol() {
@@ -104,6 +109,11 @@ public abstract class AbstractProtocol<CU extends ClientboundPacketType, CM exte
        if (logger == null) {
            logger = createLogger();
        }
+
+        // Apply shared registrations based on protocol version range
+        // Run before registerPackets, so implementations have to call append intentionally
+        applySharedRegistrations();
+
        registerPackets();
        registerConfigurationChangeHandlers();

@@ -128,6 +138,13 @@ public abstract class AbstractProtocol<CU extends ClientboundPacketType, CM exte
        }
    }

+    /**
+     * Applies shared registrations. Can be overridden to remove or add registrations.
+     */
+    protected void applySharedRegistrations() {
+        SharedRegistrations.defaultRegistrations().applyMatching(this);
+    }
+
    protected ProtocolLogger createLogger() {
        return new ProtocolLogger(getClass());
    }
@@ -177,6 +194,20 @@ public abstract class AbstractProtocol<CU extends ClientboundPacketType, CM exte
        }
    }

+    @Override
+    public void replaceClientbound(final CU type, @Nullable final PacketHandler handler) {
+        final PacketMapping mapping = clientboundMappings.mappedPacket(type.state(), type.getId());
+        Preconditions.checkNotNull(mapping, "Packet %s has no handler to replace", type);
+        mapping.setHandler(handler);
+    }
+
+    @Override
+    public void replaceServerbound(final SU type, @Nullable final PacketHandler handler) {
+        final PacketMapping mapping = serverboundMappings.mappedPacket(type.state(), type.getId());
+        Preconditions.checkNotNull(mapping, "Packet %s has no handler to replace", type);
+        mapping.setHandler(handler);
+    }
+
    private <U extends PacketType, M extends PacketType> void registerPacketIdChanges(
        Map<State, PacketTypeMap<U>> unmappedPacketTypes,
        Map<State, PacketTypeMap<M>> mappedPacketTypes,
@@ -214,6 +245,7 @@ public abstract class AbstractProtocol<CU extends ClientboundPacketType, CM exte
    @Override
    public final void loadMappingData() {
        getMappingData().load();
+        initialize();
        onMappingDataLoaded();
    }

@@ -248,10 +280,21 @@ public abstract class AbstractProtocol<CU extends ClientboundPacketType, CM exte
        }
    }

+    protected void addEntityTracker(UserConnection connection) {
+        final EntityType playerEntityType = getEntityRewriter().typeFromId("player");
+        Preconditions.checkNotNull(playerEntityType, "Player entity type not found");
+        connection.addEntityTracker(this.getClass(), new EntityTrackerBase(connection, playerEntityType));
+    }
+
    protected void addEntityTracker(UserConnection connection, EntityTracker tracker) {
        connection.addEntityTracker(this.getClass(), tracker);
    }

+    protected void addItemHasher(UserConnection connection) {
+        connection.addItemHasher(this.getClass(), new ItemHasherBase(this, connection));
+    }
+
+    @Deprecated(forRemoval = true)
    protected void addItemHasher(UserConnection connection, ItemHasher hasher) {
        connection.addItemHasher(this.getClass(), hasher);
    }
@@ -289,6 +332,46 @@ public abstract class AbstractProtocol<CU extends ClientboundPacketType, CM exte
        return packetTypesProvider.unmappedClientboundType(State.CONFIGURATION, "FINISH_CONFIGURATION");
    }

+    /**
+     * Returns the server protocol version for this protocol,
+     * or null if not set (e.g. for base protocols).
+     *
+     * @return the server protocol version
+     */
+    public @Nullable ProtocolVersion getServerVersion() {
+        return serverVersion;
+    }
+
+    /**
+     * Sets the server protocol version for this protocol.
+     * Called by the protocol manager before {@link #initialize()}.
+     *
+     * @param serverVersion the server protocol version
+     */
+    public void setServerVersion(final ProtocolVersion serverVersion) {
+        this.serverVersion = serverVersion;
+    }
+
+    /**
+     * Returns the client protocol version for this protocol,
+     * or null if not set (e.g. for base protocols).
+     *
+     * @return the client protocol version for this protocol
+     */
+    public @Nullable ProtocolVersion getClientVersion() {
+        return clientVersion;
+    }
+
+    /**
+     * Sets the client protocol version for this protocol.
+     * Called by the protocol manager before {@link #initialize()}.
+     *
+     * @param clientVersion the client protocol version for this protocol
+     */
+    public void setClientVersion(final ProtocolVersion clientVersion) {
+        this.clientVersion = clientVersion;
+    }
+
    // ---------------------------------------------------------------------------------

    @Override
@@ -297,7 +380,7 @@ public abstract class AbstractProtocol<CU extends ClientboundPacketType, CM exte
        PacketMapping packetMapping = PacketMapping.of(mappedPacketId, handler);
        if (!override && serverboundMappings.hasMapping(state, unmappedPacketId)) {
            Via.getPlatform().getLogger().log(Level.WARNING, unmappedPacketId + " already registered!" +
-                " If this override is intentional, set override to true. Stacktrace: ", new Exception());
+                " If this override is intentional, use replaceServerbound instead. Stacktrace: ", new Exception());
        }
        serverboundMappings.addMapping(state, unmappedPacketId, packetMapping);
    }
@@ -313,7 +396,7 @@ public abstract class AbstractProtocol<CU extends ClientboundPacketType, CM exte
        PacketMapping packetMapping = PacketMapping.of(mappedPacketId, handler);
        if (!override && clientboundMappings.hasMapping(state, unmappedPacketId)) {
            Via.getPlatform().getLogger().log(Level.WARNING, unmappedPacketId + " already registered!" +
-                " If override is intentional, set override to true. Stacktrace: ", new Exception());
+                " If override is intentional, use replaceClientbound instead. Stacktrace: ", new Exception());
        }
        clientboundMappings.addMapping(state, unmappedPacketId, packetMapping);
    }
@@ -373,8 +456,8 @@ public abstract class AbstractProtocol<CU extends ClientboundPacketType, CM exte

        PacketMapping packetMapping = PacketMapping.of(mappedPacketType, handler);
        if (!override && packetMappings.hasMapping(packetType)) {
-            getLogger().log(Level.WARNING, packetType + " already registered!" +
-                " If override is intentional, set override to true. Stacktrace: ", new Exception());
+            throw new IllegalArgumentException("Packet type " + packetType + " already registered! If override is intentional, use "
+                + (packetType.direction() == Direction.SERVERBOUND ? "replaceServerbound" : "replaceClientbound") + " instead.");
        }
        packetMappings.addMapping(packetType, packetMapping);
    }
@@ -443,6 +526,14 @@ public abstract class AbstractProtocol<CU extends ClientboundPacketType, CM exte
        return logger;
    }

+    public com.viaversion.viaversion.rewriter.@Nullable BlockRewriter<CU> getBlockRewriter() {
+        return null;
+    }
+
+    public @Nullable RecipeDisplayRewriter<CU> getRecipeRewriter() {
+        return null;
+    }
+
    private void printRemapError(Direction direction, State state, int unmappedPacketId, int mappedPacketId, InformativeException e) {
        // Don't print errors during handshake/login/status
        if (state != State.PLAY && direction == Direction.SERVERBOUND && !Via.getManager().debugHandler().enabled()) {
@@ -30,7 +30,7 @@ public record CodecRegistryContext(Protocol<?, ?, ?, ?> protocol, RegistryAccess

    // Generally from hardcoded, but highly variable client data
    private static final Set<StructuredDataKey<?>> NOT_IMPLEMENTED = new ReferenceOpenHashSet<>(List.of(
-        StructuredDataKey.DAMAGE_TYPE
+        StructuredDataKey.DAMAGE_TYPE1_21_11
    ));

    public CodecRegistryContext(final Protocol<?, ?, ?, ?> protocol, final RegistryAccess registryAccess, final boolean mapped) {
@@ -37,6 +37,11 @@ public class DebugSubCmd implements ViaSubCommand {
        return "Toggle various debug modes.";
    }

+    @Override
+    public String usage() {
+        return "debug [clear|pre|post], or debug <add|remove> <packet>";
+    }
+
    @Override
    public boolean execute(ViaCommandSender sender, String[] args) {
        final DebugHandler debug = Via.getManager().debugHandler();
@@ -49,11 +54,11 @@ public class DebugSubCmd implements ViaSubCommand {
                debug.clearPacketTypesToLog();
                sendMessage(sender, "&6Cleared packet types to log");
                return true;
-            } else if (args[0].equalsIgnoreCase("logpretransform")) {
+            } else if (args[0].equalsIgnoreCase("pre")) {
                debug.setLogPrePacketTransform(!debug.logPrePacketTransform());
                sendMessage(sender, "&6Pre transform packet logging is now %s", (debug.logPrePacketTransform() ? "&aenabled" : "&cdisabled"));
                return true;
-            } else if (args[0].equalsIgnoreCase("logposttransform")) {
+            } else if (args[0].equalsIgnoreCase("post")) {
                debug.setLogPostPacketTransform(!debug.logPostPacketTransform());
                sendMessage(sender, "&6Post transform packet logging is now %s", (debug.logPostPacketTransform() ? "&aenabled" : "&cdisabled"));
                return true;
@@ -75,7 +80,7 @@ public class DebugSubCmd implements ViaSubCommand {
    @Override
    public List<String> onTabComplete(final ViaCommandSender sender, final String[] args) {
        if (args.length == 1) {
-            return Arrays.asList("clear", "logposttransform", "add", "remove");
+            return Arrays.asList("clear", "pre", "post", "add", "remove");
        }
        return Collections.emptyList();
    }
@@ -37,7 +37,7 @@ public class DisplayLeaksSubCmd implements ViaSubCommand {

    @Override
    public String usage() {
-        return "displayleaks <level>";
+        return "displayleaks [level]";
    }

    @Override
@@ -78,6 +78,7 @@ public final class ConnectionDetails {
        payload.addProperty("version", clientVersion.getOriginalVersion());
        payload.addProperty("versionName", clientVersion.getName());
        payload.addProperty("versionType", clientVersion.getVersionType().name());
+        Via.getPlatform().modifyPlayerDetails(connection, payload);

        Via.getPlatform().sendCustomPayload(connection, channel, payload.toString().getBytes(StandardCharsets.UTF_8));
    }
@@ -102,6 +103,7 @@ public final class ConnectionDetails {
        payload.addProperty("version", serverVersion.getOriginalVersion());
        payload.addProperty("versionName", serverVersion.getName());
        payload.addProperty("versionType", serverVersion.getVersionType().name());
+        Via.getPlatform().modifyServerDetails(connection, payload);

        Via.getPlatform().sendCustomPayloadToClient(connection, channel, payload.toString().getBytes(StandardCharsets.UTF_8));
    }
@@ -43,6 +43,7 @@ import io.netty.channel.ChannelFuture;
 import io.netty.channel.ChannelHandlerContext;
 import io.netty.channel.ChannelPipeline;
 import io.netty.handler.codec.CodecException;
+import it.unimi.dsi.fastutil.objects.Reference2ObjectOpenHashMap;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.Map;
@@ -52,7 +53,6 @@ import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicLong;
 import java.util.function.Function;
-import it.unimi.dsi.fastutil.objects.Reference2ObjectOpenHashMap;
 import org.checkerframework.checker.nullness.qual.Nullable;

 public class UserConnectionImpl implements UserConnection {
@@ -215,7 +215,7 @@ public class EntityTrackerBase implements EntityTracker, ClientEntityIdChangeLis

    @Override
    public @Nullable DimensionData dimensionData(int dimensionId) {
-        return dimensions.values().stream().filter(data -> data.id() == dimensionId).findFirst().orElse(null); // TODO Store as array as well
+        return dimensions.values().stream().filter(data -> data.id() == dimensionId).findFirst().orElse(null);
    }

    @Override
@@ -34,8 +34,6 @@ import com.viaversion.viaversion.codec.CodecRegistryContext;
 import com.viaversion.viaversion.codec.hash.HashFunction;
 import com.viaversion.viaversion.codec.hash.HashOps;
 import it.unimi.dsi.fastutil.ints.Int2IntMap;
-import java.util.ArrayList;
-import java.util.List;
 import java.util.Map;
 import org.checkerframework.checker.nullness.qual.Nullable;

@@ -58,7 +56,7 @@ public class ItemHasherBase implements ItemHasher {
    /**
     * Returns the hashed item for the given item. Not all data may be successfully hashed.
     *
-     * @param item the item to hash
+     * @param item   the item to hash
     * @param mapped whether the item is mapped to the client version
     * @return the hashed item
     */
@@ -83,7 +81,7 @@ public class ItemHasherBase implements ItemHasher {
    /**
     * Tracks the data for the given data container, storing the original hashes via the now transformed data hashes.
     *
-     * @param customData custom_data tag
+     * @param customData         custom_data tag
     * @param originalHashedItem the original (pre-transformed) hashed item
     */
    public void trackOriginalHashedItem(final CompoundTag customData, final HashedItem originalHashedItem) {
@@ -97,7 +95,7 @@ public class ItemHasherBase implements ItemHasher {
     * Returns a copy of the original hashed item for a given custom_data hash.
     *
     * @param customDataHash custom_data hash
-     * @param clientItem the hashed item from the client that the original should be retrieved for
+     * @param clientItem     the hashed item from the client that the original should be retrieved for
     * @return the original hashed item, or null if not found
     */
    public @Nullable HashedItem originalHashedItem(final int customDataHash, final HashedItem clientItem) {
@@ -116,6 +114,8 @@ public class ItemHasherBase implements ItemHasher {
                entry.setValue(clientProvidedHash);
            }
        }
+
+        originalItem.setAmount(clientItem.amount());
        return originalItem;
    }

@@ -0,0 +1,34 @@
+/*
+ * This file is part of ViaVersion - https://github.com/ViaVersion/ViaVersion
+ * Copyright (C) 2016-2026 ViaVersion and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.viaversion.viaversion.protocol;
+
+import com.viaversion.viaversion.api.protocol.AbstractProtocol;
+import com.viaversion.viaversion.api.protocol.SimpleProtocol;
+
+/**
+ * A simple protocol which does not have any packet types.
+ * <p>
+ * {@link AbstractProtocol} should be preferred over this class in most cases.
+ */
+public abstract class AbstractSimpleProtocol extends AbstractProtocol<SimpleProtocol.DummyPacketTypes, SimpleProtocol.DummyPacketTypes,
+    SimpleProtocol.DummyPacketTypes, SimpleProtocol.DummyPacketTypes> implements SimpleProtocol {
+
+    protected AbstractSimpleProtocol() {
+        super(null, null, null, null);
+    }
+}
Author	SHA1	Message	Date
Nassim Jahnke	4738945a7a	5.9.0 Release	2026-04-19 15:36:05 +02:00
Florian Reuth	4c55ef9cab	Remove rewriter overrides in AbstractProtocol (#4913 )	2026-04-19 08:30:13 +02:00
Niko	a66dbf77aa	Fix profile with multiple properties of the same key in 1.20.5->1.20.3 (#4909 )	2026-04-17 22:33:28 +02:00
Nassim Jahnke	c6cc380c3c	Fix fluid block counting Fixes #4912	2026-04-17 14:44:57 +02:00
Acrylic Style	cd3f146781	Fix block state translation in falling block (#4910 ) Fixes #4908	2026-04-15 20:31:15 +02:00
Florian Reuth	d0da13edd8	Add missing tags for client-interaction in 1.21.11->26.1 (#4906 ) Fixes swing animation when placing plants and some container-specific interactions	2026-04-10 14:57:50 +02:00
Nassim Jahnke	ec1f570f4b	Update 26.1 protocol version range	2026-04-09 13:38:39 +02:00
Nassim Jahnke	e41e216903	Fix jukebox_song registry key in 1.21.11->26.1	2026-04-07 21:03:59 +02:00
Nassim Jahnke	43ee417e20	[ci skip] Update template protocol, clean up imports and indents	2026-04-06 15:47:22 +02:00
Nassim Jahnke	4dc57e3d53	Make entity data type id mapping less manual	2026-04-06 13:34:19 +02:00
Nassim Jahnke	31f257fee1	Register empty handlers for transient data components in 1.20.5->1.20.3	2026-04-05 18:58:03 +02:00
Nassim Jahnke	cda72574fc	Change tag type in 1.20.2 block entity	2026-04-04 17:42:05 +02:00
Nassim Jahnke	ef1b6a10ea	Fix ocelot parent entity type	2026-04-04 14:59:32 +02:00
Nassim Jahnke	c45c700301	Fix 1.21 player chat read type	2026-04-02 16:13:39 +02:00
Nassim Jahnke	c43de2b88d	Move 26.1 container empty item handling into proper upgrade/downgrade methods	2026-04-02 15:10:19 +02:00
Drex	898b6c8774	Improve enchantment term conversion (#4879 )	2026-04-02 14:32:48 +02:00
Florian Reuth	2e3c47d292	Track sneaking state for secondary action in 1.21.11->26.1 (#4890 )	2026-04-02 13:23:16 +02:00
Florian Reuth	7974d1a570	[ci skip] Update missing year references (#4786 )	2026-04-02 11:56:51 +02:00
Florian Reuth	cf2c1c5b76	Update time command translations in 1.21.11->26.1 (#4891 )	2026-04-02 11:47:55 +02:00
Florian Reuth	d75c54cc70	Fix kick when opening "edit game rules" screen (#4882 )	2026-04-02 11:44:50 +02:00
Florian Reuth	ead13b2bb9	Deprecate packet register methods with override boolean (#4881 ) Replaced by Protocol#registerClientbound & Protocol#registerServerbound	2026-04-01 17:24:33 +02:00
Nassim Jahnke	2e91b841b0	Automatically call mapTypes in entity rewriter	2026-04-01 17:21:53 +02:00
Nassim Jahnke	50486fa43a	Don't apply shared registrations to differing version types	2026-04-01 17:05:07 +02:00
Nassim Jahnke	31d4cd453d	Add 26.1.1 to version string	2026-04-01 13:02:29 +02:00
Nassim Jahnke	c5482b99bf	[ci skip] Update error message	2026-03-31 21:15:01 +02:00
Nassim Jahnke	98ef806887	Fix baby wolf assets	2026-03-31 15:21:48 +02:00
Florian Reuth	a26745862f	Handle show_dialog click events (#4878 )	2026-03-31 14:36:09 +02:00
Florian ReuthandNassim Jahnke	6bd081cefd	Handle in-depth components in dialogs (#4876 ) Co-authored-by: Nassim Jahnke <nassim@njahnke.dev>	2026-03-31 11:25:47 +02:00
Nassim Jahnke	bb9aa8b31c	Fix adventure mode predicate index check in 1.20.4->1.20.5	2026-03-31 11:07:01 +02:00
Nassim Jahnke	572f7a2677	Fix hashing of attribute_modifiers with override text	2026-03-30 23:29:20 +02:00
Nassim Jahnke	11a5c9e32c	Fix block entity tag read type	2026-03-30 23:09:37 +02:00
Nassim Jahnke	02b65dcb36	Fix command rewriter check being too early	2026-03-30 22:32:08 +02:00
Nassim Jahnke	0121534e7e	Deduplicate particle type fillers	2026-03-30 21:53:47 +02:00
Florian Reuth	941e6f6df4	Null check block entity tag in 1.20->1.20.2 (#4872 )	2026-03-30 20:40:26 +02:00
Nassim Jahnke	fe6e18845b	Make tests fail if error occurs during platform	2026-03-30 20:40:26 +02:00
Nassim Jahnke	8f8f5e72c0	Default rewriter registrations across protocols In total it doesn't (yet) reduce the lines of code (though there is also some other changes adding code here), but makes adding single rewriter calls to a range of protocols much easier than having to individually check an ever increasing number of classes. This also moved Protocol#registerPackets until after mappings have been loaded (which makes onMappingDataLoaded redundant for now, but will become relevant later again)	2026-03-30 20:40:25 +02:00
Nassim Jahnke	a6c35c6519	5.8.1 Release	2026-03-30 20:28:09 +02:00
Nassim Jahnke	8b115c7fde	Fix attack_range and provides_banner_pattern hashing	2026-03-30 20:22:40 +02:00
Florian Reuth	e2d3874f6d	Add debug command usage help (#4874 )	2026-03-30 15:25:21 +02:00
Florian Reuth	26d8190b23	Send empty tags packet in 1.21.11->26.1 (#4871 )	2026-03-29 21:37:32 +02:00
RK_01	d508b6cec1	Add missing fluid block states for kelp, seagrass, and bubble columns (#4870 ) Fixes water physics in 26.1	2026-03-29 17:36:08 +02:00
Nassim Jahnke	916ef8c5ac	Fix removal of recipe displays	2026-03-29 15:07:44 +02:00
Nassim Jahnke	6b74116ff1	Handle item changes in dialog packets	2026-03-28 17:09:25 +01:00
Nassim Jahnke	5ead6805b9	Distinguish items of different ids for hashing	2026-03-28 11:25:22 +01:00
Nassim Jahnke	a6eedfdf0b	Bump version to 5.8.1-SNAPSHOT	2026-03-28 11:18:20 +01:00
Nassim Jahnke	38ecd65ee8	5.8.0 Release	2026-03-27 16:12:18 +01:00
Nassim Jahnke	788c1d1b1f	Set hashed item amount from click packet Preserves the amount the player actually had/saw at the end	2026-03-26 20:44:52 +01:00
Nassim Jahnke	0519184da2	Replace 0 count in item hovers	2026-03-25 16:21:55 +01:00
Florian Reuth	fd13912295	Fix EntityDataTypes1_21_11#villagerDataType typo	2026-03-25 16:21:23 +01:00
Nassim Jahnke	8d3c36de06	Send empty tags packet if not sent early enough when leaving config stage Some tags are required before the client finalizes its registries, this lets Via fill them up early enough in later protocols	2026-03-25 16:21:09 +01:00
Nassim Jahnke	219d374d7c	Fix item particle type	2026-03-25 16:21:09 +01:00
Nassim Jahnke	9b163e70c3	Remove snapshot bit	2026-03-25 16:21:09 +01:00
Nassim Jahnke	9ed00904f9	26.1-rc-3	2026-03-25 16:21:09 +01:00
Nassim Jahnke	e56abf5cac	Update identifier files	2026-03-25 16:21:09 +01:00
Florian Reuth	1bf7274dc8	Add empty damage type & banner pattern tags Signed-off-by: Florian Reuth <git@florianreuth.de>	2026-03-25 16:21:09 +01:00
Nassim Jahnke	d218451418	26.1-rc-2	2026-03-25 16:21:08 +01:00
Nassim Jahnke	7d8dcce307	Fix pausing daylight cycle	2026-03-25 16:21:08 +01:00
Nassim Jahnke	2f5d527a38	Fix blocks attacks conversion and banner pattern hashing	2026-03-25 16:21:08 +01:00
Nassim Jahnke	a16c5a9fc5	26.1-rc-1	2026-03-25 16:21:08 +01:00
Nassim Jahnke	318608b9cd	Auto remove new registries from tags too	2026-03-25 16:21:08 +01:00
Nassim Jahnke	ae7496fbad	26.1-pre-3	2026-03-25 16:21:07 +01:00
Nassim Jahnke	32a1dfe74f	26.1-pre-2	2026-03-25 16:21:07 +01:00
Nassim Jahnke	815ec24af1	Remove removed registries from command arguments	2026-03-25 16:21:07 +01:00
Nassim Jahnke	8ee0b66eed	Always send interact_at	2026-03-25 16:21:07 +01:00
Nassim Jahnke	ab2385b975	26.1-pre1	2026-03-25 16:21:07 +01:00
Nassim Jahnke	5a9ccf7c17	Update villager entity data id	2026-03-25 16:21:07 +01:00
Nassim Jahnke	22877d06a7	Replace remaining either holders	2026-03-25 16:21:06 +01:00
Nassim Jahnke	35d85d08a7	Update sound variants	2026-03-25 16:21:06 +01:00
Nassim Jahnke	f5bb1c42db	26.1-snapshot-11	2026-03-25 16:21:06 +01:00
Nassim Jahnke	cfb8519ae2	26.1-snapshot-10	2026-03-25 16:21:06 +01:00
Nassim Jahnke	4d1fa925ff	Add new ambient light colors	2026-03-25 16:21:06 +01:00
Nassim Jahnke	fa410b704a	Fix cat variant asset change	2026-03-25 16:21:06 +01:00
Nassim Jahnke	483628f1f2	26.1-snapshot-9	2026-03-25 16:21:05 +01:00
Nassim Jahnke	7930e66676	26.1-snapshot-8 (maybe)	2026-03-25 16:21:05 +01:00
Nassim Jahnke	5b547a303a	26.1-snapshot-7	2026-03-25 16:21:05 +01:00
Nassim Jahnke	497d8e17da	26.1-snapshot-6	2026-03-25 16:21:05 +01:00
Nassim Jahnke	efbd5d23cd	26.1-snapshot-5	2026-03-25 16:21:05 +01:00
Nassim Jahnke	592b8c8d47	26.1-snapshot-4	2026-03-25 16:21:04 +01:00
Nassim Jahnke	5393edc35b	Handle null template items, fix asset id change	2026-03-25 16:21:04 +01:00
Nassim Jahnke	97aff00ced	Fill registries used by delayed item loading	2026-03-25 16:21:04 +01:00
Nassim Jahnke	69121c5722	26.1-snapshot-3	2026-03-25 16:21:04 +01:00
Nassim Jahnke	ba57197552	26.1-snapshot-2	2026-03-25 16:21:04 +01:00
Nassim Jahnke	7ca372dca4	Update template protocol	2026-03-25 16:21:04 +01:00
Nassim Jahnke	e9fb10b63c	26.1-snapshot-1	2026-03-25 16:21:03 +01:00
Florian Reuth	ca7696ce12	Allow platforms to append data to connection details protocols (#4859 )	2026-03-24 23:17:48 +01:00
Florian Reuth	e63c806d64	Fix custom potion effects translation in 1.20.3->1.20.5 (#4858 )	2026-03-22 08:34:30 +01:00
Florian Reuth	e470ca0002	[ci skip] Update README (#4856 )	2026-03-21 19:07:32 +01:00
Florian Reuth	80e90a4401	Fix flower pot block storage 1.12.2->1.13 memory leak (#4852 )	2026-03-18 15:05:30 +01:00
Florian Reuth	1d35f2ec35	Produce inlined string in 1.8->1.9 sign update (#4851 )	2026-03-16 19:17:21 +01:00
Nassim Jahnke	e639eb763a	Update ViaNBT	2026-03-13 20:51:32 +01:00
Nassim Jahnke	d8343d278d	Use var int type in holder set type	2026-03-12 15:12:09 +01:00
Nassim Jahnke	833f49fff3	Swap end and overworld background tracks	2026-03-02 17:33:52 +01:00