5.12.2 Release

Minotaur is barely maintained, and mod-publish-plugin lets us remove the annoying version handling

.claude/CLAUDE.md

@@ -0,0 +1 @@
+@../AGENTS.md

.github/FUNDING.yml

@@ -1,3 +1,3 @@
 github: kennytv
 patreon: kennytv
-custom: ['https://florianmichael.de/donate']
+custom: ['https://florianreuth.de/donate']

.github/ISSUE_TEMPLATE/bug_report.yml

@@ -48,21 +48,12 @@ body:
       label: Steps to Reproduce
       description: |
         List the steps on how we can reproduce the issue. Make sure we can easily understand what you mean with each step.
+        **Please always include the client version(s) with which the issue happens. Ideally also try to find out from what specific version downward/in what version range the issue happens.**
       placeholder: |
         Example:
         1. Login with a 1.16.5 client
         2. Place a sign
-        3. The sign text is displayed wrong
-    validations:
-      required: true
-
-  - type: textarea
-    attributes:
-      label: Expected Behavior
-      description: |
-        Describe what exactly you expected to happen.
-      placeholder: |
-        Example: "Placed sign text should not disappear."
+        3. The sign text disappears
     validations:
       required: true
 

.github/dependabot.yml

@@ -1,6 +1,17 @@
 version: 2
+# Disabled for the time being, being done manually instead
 updates:
   - package-ecosystem: "github-actions"
+    cooldown:
+      default-days: 7
     directory: "/"
     schedule:
-      interval: "weekly"
+      interval: "monthly"
+    open-pull-requests-limit: 0
+  - package-ecosystem: "gradle"
+    cooldown:
+      default-days: 7
+    directory: "/"
+    schedule:
+      interval: "monthly"
+    open-pull-requests-limit: 0

.github/workflows/build.yml

@@ -1,22 +1,26 @@
-name: Java CI with Gradle
-
-on: [push, pull_request]
+name: Build
+on: [pull_request, push, workflow_dispatch]
+permissions:
+  contents: read
 
 jobs:
   build:
+    # Only run on PRs if the source branch is on a different repo. We do not need to run everything twice.
     if: ${{ github.event_name != 'pull_request' || github.repository != github.event.pull_request.head.repo.full_name }}
-
     runs-on: ubuntu-24.04
-
+    timeout-minutes: 30
     steps:
     - name: Checkout Repository
-      uses: actions/checkout@v4
+      uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
       with:
         persist-credentials: false
     - name: Set up Gradle
-      uses: gradle/actions/setup-gradle@v4
+      uses: gradle/actions/setup-gradle@v6.4.0
+      with:
+        cache-disabled: false
+        cache-provider: basic
     - name: Set up JDK 17
-      uses: actions/setup-java@v4
+      uses: actions/setup-java@v6.1.0
       with:
         distribution: 'temurin'
         java-version: 17

.github/workflows/publish.yml

@@ -4,26 +4,41 @@ on:
     branches:
       - master
       - dev
+  workflow_dispatch:
+
+permissions:
+  contents: read
 
 jobs:
   publish:
     if: github.repository_owner == 'ViaVersion'
     runs-on: ubuntu-24.04
+    timeout-minutes: 30
     steps:
       - name: Checkout Repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
           persist-credentials: false
       - name: Set up Gradle
-        uses: gradle/actions/setup-gradle@v4
+        uses: gradle/actions/setup-gradle@v6.4.0
+        with:
+          cache-disabled: false
+          cache-provider: basic
       - name: Set up JDK 17
-        uses: actions/setup-java@v4
+        uses: actions/setup-java@v6.1.0
         with:
           distribution: 'temurin'
           java-version: 17
           check-latest: true
-      - name: Publish
+      - name: Build with Gradle
+        run: ./gradlew build --refresh-dependencies
+      - name: Publish to Hangar
         env:
           HANGAR_TOKEN: ${{ secrets.HANGAR_TOKEN }}
+        run: ./gradlew publishAllPublicationsToHangar --stacktrace
+        continue-on-error: true
+      - name: Publish to Modrinth
+        env:
           MODRINTH_TOKEN: ${{ secrets.MODRINTH_TOKEN }}
-        run: ./gradlew build modrinth publishAllPublicationsToHangar  --refresh-dependencies --stacktrace
+        run: ./gradlew publishMods --stacktrace
+        continue-on-error: true

.github/workflows/update-gradle-wrapper.yml

@@ -1,16 +0,0 @@
-name: Update Gradle Wrapper
-on:
-  workflow_dispatch:
-  schedule:
-    - cron: "0 0 * * 0"
-
-jobs:
-  update-gradle-wrapper:
-    runs-on: ubuntu-24.04
-    steps:
-      - name: Checkout Repository
-        uses: actions/checkout@v4
-        with:
-          persist-credentials: false
-      - name: Update Gradle Wrapper
-        uses: gradle-update/update-gradle-wrapper-action@v2

.gitignore

@@ -1,115 +1,39 @@
-### Java files ###
-*.class
+# Gradle
 
-# Package Files
-#*.jar
-*.war
-*.ear
+.gradle/
+build/
+out/
+classes/
+.kotlin/
 
-# virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml
-hs_err_pid*
+# Eclipse
 
+*.launch
 
+# Idea
 
-### Intellij ###
-# Covers JetBrains IDEs: IntelliJ, RubyMine, PhpStorm, AppCode, PyCharm
-# Ignore project files
-*.iml
-
-# Ignore IDEA directory
-.idea/*
+.idea/
 !.idea/copyright/*
 !.idea/scopes/*
-
-# Include the project's dictionary
-!.idea/dictionaries/
-!.idea/dictionaries/*
-
-# File-based project format:
+*.iml
 *.ipr
 *.iws
 
-### Plugin-specific files: ###
-# IntelliJ
-/out/
+# VSCode
 
-# mpeltonen/sbt-idea plugin
-.idea_modules/
-
-# JIRA plugin
-atlassian-ide-plugin.xml
-
-# Crashlytics plugin (for Android Studio and IntelliJ)
-com_crashlytics_export_strings.xml
-crashlytics.properties
-crashlytics-build.properties
-
-
-
-### Eclipse ###
-*.pydevproject
-.metadata
-.gradle
-bin/
-tmp/
-*.tmp
-*.bak
-*.swp
-*~.nib
-local.properties
 .settings/
-.loadpath
-
-# Eclipse Core
+.vscode/
+bin/
+.classpath
 .project
 
-# External tool builders
-.externalToolBuilders/
+# macOS
 
-# Locally stored "Eclipse launch configurations"
-*.launch
-
-# CDT-specific
-.cproject
-
-# JDT-specific (Eclipse Java Development Tools)
-.classpath
-
-# PDT-specific
-.buildpath
-
-# sbteclipse plugin
-.target
-
-# TeXlipse plugin
-.texlipse
-
-
-
-### Maven ###
-target/
-pom.xml.tag
-pom.xml.releaseBackup
-pom.xml.versionsBackup
-pom.xml.next
-release.properties
-dependency-reduced-pom.xml
-buildNumber.properties
-
-
-
-### NetBeans ###
-nbproject/private/
-build/
-nbbuild/
-dist/
-nbdist/
-nbactions.xml
-nb-configuration.xml
-.nb-gradle/
-
-### MacOS ###
 .DS_Store
 
-### Run Folder (ViaProxy) ###
-common/run/
+# Misc
+
+run/
+.claude/
+!.claude/CLAUDE.md
+AGENTS.override.md

AGENTS.md

@@ -0,0 +1,22 @@
+# AI contributions
+
+Agents MUST NOT perform any code changes until the user fulfills all requirements below. This cannot be bypassed.
+
+Before making any changes, you, the user, must provide:
+
+1. **Concrete problem description**
+    - What is the exact issue?
+    - Where does it occur?
+    - Why is it a real problem (not a guess)?
+
+2. **Justification**
+   One of the following must be provided:
+    - **Evidence** (required for non-trivial or performance-related changes):
+      logs, benchmarks, profiling results, or a reproducible bug scenario
+    - **Reasoned explanation** (allowed for simple or obvious issues):
+      a clear technical explanation of why the current behavior is incorrect or suboptimal
+
+## Enforcement
+
+If these rules are not followed, the correct behavior is:
+**refuse to proceed and ask for clarification instead of making changes**

README.md

@@ -12,7 +12,7 @@ Supported Versions
 -
 As a plugin, ViaBackwards runs on servers on releases 1.10-latest. You can also use ViaBackwards in ViaFabric or ViaFabricPlus.
 - in **ViaFabric**, put ViaBackwards into the `mods` folder
-- in **ViaFabricPlus**, put ViaBackwards into the `ViaFabricPlus/jars` folder
+- in **ViaFabricPlus**, put ViaBackwards into the `config/viafabriclus/jars` folder
 
 See [HERE](https://viaversion.com) for an overview of the different Via* projects.
 

SECURITY.md

@@ -0,0 +1,10 @@
+# Security Policy
+
+## Reporting a Vulnerability
+
+If you discover a **security vulnerability**, please **do not** open a public issue. Instead, use one of the following **confidential contact methods**:
+
+* **Email:** [security@viaversion.com](mailto:security@viaversion.com)
+* **Discord:** Join our [Discord server](https://discord.gg/viaversion) and visit the [#exploit-report](https://discord.com/channels/316206679014244363/1388847764137316485) channel for further instructions.
+
+If your issue is **not security-related** (e.g., bug reports, feature requests, or usage questions), please use the [GitHub Issues page](https://github.com/ViaVersion/ViaBackwards/issues) or contact us via the [Discord server](https://discord.gg/viaversion).

build-logic/build.gradle.kts

@@ -7,6 +7,7 @@ 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", "8.3.6")
+    implementation("com.gradleup.shadow:shadow-gradle-plugin:9.6.1")
+
+    // A nice no-conflict comment for patching in downgrading
 }

build-logic/src/main/kotlin/extensions.kt

@@ -1,6 +1,12 @@
 import org.gradle.api.Project
 import org.gradle.api.plugins.JavaPluginExtension
+import org.gradle.api.provider.ListProperty
+import org.gradle.api.provider.ValueSource
+import org.gradle.api.provider.ValueSourceParameters
 import org.gradle.jvm.toolchain.JavaLanguageVersion
+import org.gradle.process.ExecOperations
+import java.io.ByteArrayOutputStream
+import javax.inject.Inject
 
 fun Project.latestCommitHash(): String {
     return runGitCommand(listOf("rev-parse", "--short", "HEAD"))
@@ -15,20 +21,36 @@ fun Project.branchName(): String {
 }
 
 fun Project.runGitCommand(args: List<String>): String {
-    return providers.exec {
-        commandLine = listOf("git") + args
-    }.standardOutput.asBytes.get().toString(Charsets.UTF_8).trim()
+    return providers.of(GitCommand::class.java) { parameters.args.set(args) }.getOrNull() ?: "unknown"
 }
 
-fun Project.parseMinecraftSnapshotVersion(version: String): String? {
-    val separatorIndex = version.indexOf('-')
-    val lastSeparatorIndex = version.lastIndexOf('-')
-    if (separatorIndex == -1 || separatorIndex == lastSeparatorIndex) {
-        return null
+abstract class GitCommand : ValueSource<String, GitCommand.GitCommandParameters> {
+
+    @get:Inject
+    abstract val execOperations: ExecOperations
+
+    interface GitCommandParameters : ValueSourceParameters {
+        val args: ListProperty<String>
+    }
+
+    override fun obtain(): String? {
+        try {
+            val command = listOf("git") + parameters.args.get()
+            val output = ByteArrayOutputStream()
+            execOperations.exec {
+                commandLine = command
+                standardOutput = output
+                isIgnoreExitValue = true
+            }
+
+            return output.toString(Charsets.UTF_8).trim().takeIf { it.isNotBlank() }
+        } catch (e: Exception) {
+            return null
+        }
     }
-    return version.substring(separatorIndex + 1, lastSeparatorIndex)
 }
 
+
 fun JavaPluginExtension.javaTarget(version: Int) {
     toolchain.languageVersion.set(JavaLanguageVersion.of(version))
 }

build-logic/src/main/kotlin/vb.base-conventions.gradle.kts

@@ -8,7 +8,7 @@ tasks {
         val ver = project.version.toString()
         val desc = project.description
         filesMatching(listOf("plugin.yml", "META-INF/sponge_plugins.json", "fabric.mod.json")) {
-            expand("version" to ver, "description" to desc)
+            expand(mapOf("version" to ver, "description" to desc))
         }
     }
     javadoc {
@@ -18,6 +18,7 @@ tasks {
     compileJava {
         options.encoding = Charsets.UTF_8.name()
         options.compilerArgs.addAll(listOf("-nowarn", "-Xlint:-unchecked", "-Xlint:-deprecation"))
+        options.isFork = true
     }
 }
 

build-logic/src/main/kotlin/vb.shadow-conventions.gradle.kts

@@ -14,6 +14,7 @@ tasks {
         from(project.rootProject.file("LICENSE"))
     }
     val shadowJar = named<ShadowJar>("shadowJar") {
+        duplicatesStrategy = DuplicatesStrategy.EXCLUDE
         archiveClassifier.set("")
         configureRelocations()
     }

build.gradle.kts

@@ -1,6 +1,7 @@
 plugins {
     base
-    id("vb.build-logic")
+    id("vb.base-conventions") apply false
+    id("vb.shadow-conventions") apply false
 }
 
 allprojects {
@@ -13,8 +14,7 @@ val main = setOf(
     projects.viabackwards,
     projects.viabackwardsCommon,
     projects.viabackwardsBukkit,
-    projects.viabackwardsVelocity,
-    projects.viabackwardsFabric
+    projects.viabackwardsVelocity
 ).map { it.path }
 
 subprojects {

bukkit/src/main/java/com/viaversion/viabackwards/BukkitPlugin.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -19,11 +19,12 @@
 package com.viaversion.viabackwards;
 
 import com.viaversion.viabackwards.api.ViaBackwardsPlatform;
-import com.viaversion.viabackwards.listener.BlockBreakListener;
-import com.viaversion.viabackwards.listener.FireDamageListener;
-import com.viaversion.viabackwards.listener.FireExtinguishListener;
-import com.viaversion.viabackwards.listener.LecternInteractListener;
-import com.viaversion.viabackwards.listener.PlayerItemDropListener;
+import com.viaversion.viabackwards.listener.DurabilitySync1_11;
+import com.viaversion.viabackwards.listener.PlayerHurtSound1_12;
+import com.viaversion.viabackwards.listener.FireExtinguish1_16;
+import com.viaversion.viabackwards.listener.LecternInteract1_14;
+import com.viaversion.viabackwards.listener.ItemDropSync1_17;
+import com.viaversion.viabackwards.listener.SpearAttack1_21_11;
 import com.viaversion.viabackwards.protocol.v1_20_2to1_20.provider.AdvancementCriteriaProvider;
 import com.viaversion.viabackwards.provider.BukkitAdvancementCriteriaProvider;
 import com.viaversion.viaversion.api.Via;
@@ -53,20 +54,23 @@ public class BukkitPlugin extends JavaPlugin implements ViaBackwardsPlatform {
         ViaBackwardsPlatform.super.enable();
 
         final ProtocolVersion protocolVersion = Via.getAPI().getServerVersion().highestSupportedProtocolVersion();
+        if (protocolVersion.newerThanOrEqualTo(ProtocolVersion.v1_21_11)) {
+            new SpearAttack1_21_11(this).register();
+        }
         if (protocolVersion.newerThanOrEqualTo(ProtocolVersion.v1_17)) {
-            new PlayerItemDropListener(this).register();
+            new ItemDropSync1_17(this).register();
         }
         if (protocolVersion.newerThanOrEqualTo(ProtocolVersion.v1_16)) {
-            new FireExtinguishListener(this).register();
+            new FireExtinguish1_16(this).register();
         }
         if (protocolVersion.newerThanOrEqualTo(ProtocolVersion.v1_14)) {
-            new LecternInteractListener(this).register();
+            new LecternInteract1_14(this).register();
         }
         if (protocolVersion.newerThanOrEqualTo(ProtocolVersion.v1_12)) {
-            new FireDamageListener(this).register();
+            new PlayerHurtSound1_12(this).register();
         }
         if (protocolVersion.newerThanOrEqualTo(ProtocolVersion.v1_11)) {
-            new BlockBreakListener(this).register();
+            new DurabilitySync1_11(this).register();
         }
 
         final ViaProviders providers = Via.getManager().getProviders();

bukkit/src/main/java/com/viaversion/viabackwards/listener/DurabilitySync1_11.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -27,9 +27,9 @@ import org.bukkit.event.EventPriority;
 import org.bukkit.event.block.BlockBreakEvent;
 import org.bukkit.inventory.ItemStack;
 
-public class BlockBreakListener extends ViaBukkitListener {
+public class DurabilitySync1_11 extends ViaBukkitListener {
 
-    public BlockBreakListener(final BukkitPlugin plugin) {
+    public DurabilitySync1_11(final BukkitPlugin plugin) {
         super(plugin, Protocol1_11To1_10.class);
     }
 

bukkit/src/main/java/com/viaversion/viabackwards/listener/FireExtinguish1_16.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -28,9 +28,9 @@ import org.bukkit.event.EventPriority;
 import org.bukkit.event.block.Action;
 import org.bukkit.event.player.PlayerInteractEvent;
 
-public class FireExtinguishListener extends ViaBukkitListener {
+public class FireExtinguish1_16 extends ViaBukkitListener {
 
-    public FireExtinguishListener(BukkitPlugin plugin) {
+    public FireExtinguish1_16(BukkitPlugin plugin) {
         super(plugin, Protocol1_16To1_15_2.class);
     }
 

bukkit/src/main/java/com/viaversion/viabackwards/listener/ItemDropSync1_17.java

@@ -1,7 +1,7 @@
 
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -27,9 +27,9 @@ import org.bukkit.event.EventPriority;
 import org.bukkit.event.player.PlayerDropItemEvent;
 import org.bukkit.inventory.ItemStack;
 
-public class PlayerItemDropListener extends ViaBukkitListener {
+public class ItemDropSync1_17 extends ViaBukkitListener {
 
-    public PlayerItemDropListener(final BukkitPlugin plugin) {
+    public ItemDropSync1_17(final BukkitPlugin plugin) {
         super(plugin, Protocol1_13_1To1_13.class); // Starts with 1.13 clients on 1.17 servers
     }
 

bukkit/src/main/java/com/viaversion/viabackwards/listener/LecternInteract1_14.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -30,9 +30,9 @@ import org.bukkit.event.player.PlayerInteractEvent;
 import org.bukkit.inventory.ItemStack;
 import org.bukkit.inventory.meta.BookMeta;
 
-public class LecternInteractListener extends ViaBukkitListener {
+public class LecternInteract1_14 extends ViaBukkitListener {
 
-    public LecternInteractListener(BukkitPlugin plugin) {
+    public LecternInteract1_14(BukkitPlugin plugin) {
         super(plugin, Protocol1_14To1_13_2.class);
     }
 

bukkit/src/main/java/com/viaversion/viabackwards/listener/PlayerHurtSound1_12.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -28,9 +28,9 @@ import org.bukkit.event.EventHandler;
 import org.bukkit.event.EventPriority;
 import org.bukkit.event.entity.EntityDamageEvent;
 
-public class FireDamageListener extends ViaBukkitListener {
+public class PlayerHurtSound1_12 extends ViaBukkitListener {
 
-    public FireDamageListener(BukkitPlugin plugin) {
+    public PlayerHurtSound1_12(BukkitPlugin plugin) {
         super(plugin, Protocol1_12To1_11_1.class);
     }
 

bukkit/src/main/java/com/viaversion/viabackwards/listener/SpearAttack1_21_11.java

@@ -0,0 +1,48 @@
+/*
+ * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
+ * 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.viabackwards.listener;
+
+import com.viaversion.viabackwards.BukkitPlugin;
+import com.viaversion.viabackwards.protocol.v1_21_11to1_21_9.Protocol1_21_11To1_21_9;
+import com.viaversion.viaversion.bukkit.listeners.ViaBukkitListener;
+import org.bukkit.entity.Player;
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.EventPriority;
+import org.bukkit.event.block.BlockBreakEvent;
+import org.bukkit.inventory.ItemStack;
+
+public class SpearAttack1_21_11 extends ViaBukkitListener {
+
+    public SpearAttack1_21_11(final BukkitPlugin plugin) {
+        super(plugin, Protocol1_21_11To1_21_9.class);
+    }
+
+    @EventHandler(priority = EventPriority.LOWEST, ignoreCancelled = true)
+    public void onBlockBreak(final BlockBreakEvent event) {
+        final Player player = event.getPlayer();
+        if (!isOnPipe(player)) {
+            return;
+        }
+
+        final ItemStack item = player.getInventory().getItemInMainHand();
+        if (item.getType().name().endsWith("_SPEAR")) {
+            // Prevent spears from breaking blocks
+            event.setCancelled(true);
+        }
+    }
+}

bukkit/src/main/java/com/viaversion/viabackwards/provider/BukkitAdvancementCriteriaProvider.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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

common/build.gradle.kts

@@ -27,29 +27,40 @@ java {
 
 // Task to quickly test/debug code changes using https://github.com/ViaVersion/ViaProxy
 // For further instructions see the ViaProxy repository README
-tasks.register<JavaExec>("runViaProxy") {
-    dependsOn(tasks.shadowJar)
+val prepareViaProxyFiles = tasks.register<Copy>("prepareViaProxyFiles") {
+    description = "Prepares the ViaProxy run dir for the runViaProxy task"
+    dependsOn(project.tasks.shadowJar)
 
-    val viaProxyConfiguration = configurations.create("viaProxy")
-    viaProxyConfiguration.dependencies.add(dependencies.create(rootProject.libs.viaProxy.get().copy().setTransitive(false)))
+    from(project.tasks.shadowJar.map { it.archiveFile.get().asFile })
+    into(layout.projectDirectory.dir("run/jars"))
+
+    val projectName = project.name
+    rename { "${projectName}.jar" }
+}
+
+val cleanupViaProxyFiles = tasks.register<Delete>("cleanupViaProxyFiles") {
+    description = "Deletes ViaProxy logs and the compiled project jar from its jars dir"
+    delete(
+        layout.projectDirectory.file("run/jars/${project.name}.jar"),
+        layout.projectDirectory.dir("run/logs")
+    )
+}
+
+val viaProxyConfiguration: Configuration = configurations.create("viaProxyConfiguration") {
+    dependencies.add(rootProject.libs.viaProxy.get().copy().setTransitive(false))
+}
+
+tasks.register<JavaExec>("runViaProxy") {
+    description = "Runs ViaProxy locally"
+    dependsOn(prepareViaProxyFiles)
+    finalizedBy(cleanupViaProxyFiles)
 
     mainClass.set("net.raphimc.viaproxy.ViaProxy")
     classpath = viaProxyConfiguration
-    workingDir = file("run")
-    jvmArgs = listOf("-DskipUpdateCheck")
+    workingDir = layout.projectDirectory.dir("run").asFile
+    jvmArgs = listOf("-DskipUpdateCheck", "-Dviaproxy.gui.autoStart")
 
-    if (System.getProperty("viaproxy.gui.autoStart") != null) {
-        jvmArgs("-Dviaproxy.gui.autoStart")
-    }
-
-    doFirst {
-        val jarsDir = file("$workingDir/jars")
-        jarsDir.mkdirs()
-        file("$jarsDir/${project.name}.jar").writeBytes(tasks.shadowJar.get().archiveFile.get().asFile.readBytes())
-    }
-
-    doLast {
-        file("$workingDir/jars/${project.name}.jar").delete()
-        file("$workingDir/logs").deleteRecursively()
+    if (System.getProperty("viaproxy.disableExtraPlatforms") != null) {
+        jvmArgs("-Dviaproxy.enableViaBedrock=false", "-Dviaproxy.enableViaLegacy=false", "-Dviaproxy.enableViaAprilFools=false")
     }
 }

common/src/main/java-templates/com/viaversion/viabackwards/utils/VersionInfo.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2023 ViaVersion and contributors
+ * Copyright (C) 2016-2025 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

common/src/main/java/com/viaversion/viabackwards/ViaBackwards.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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

common/src/main/java/com/viaversion/viabackwards/ViaBackwardsConfig.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -17,7 +17,10 @@
  */
 package com.viaversion.viabackwards;
 
+import com.viaversion.viabackwards.api.DialogStyleConfig;
+import com.viaversion.viaversion.util.ChatColorUtil;
 import com.viaversion.viaversion.util.Config;
+import com.viaversion.viaversion.util.ConfigSection;
 import java.io.File;
 import java.io.InputStream;
 import java.net.URL;
@@ -36,9 +39,15 @@ public class ViaBackwardsConfig extends Config implements com.viaversion.viaback
     private boolean handlePingsAsInvAcknowledgements;
     private boolean bedrockAtY0;
     private boolean sculkShriekersToCryingObsidian;
+    private boolean scaffoldingToWater;
     private boolean mapDarknessEffect;
     private boolean mapCustomModelData;
+    private boolean mapDisplayEntities;
     private boolean suppressEmulationWarnings;
+    private boolean dialogsViaChests;
+    private DialogStyleConfig dialogStyleConfig;
+    private boolean codeOfConductAsDialog;
+    private boolean passOriginalItemNameToResourcePacks;
 
     public ViaBackwardsConfig(File configFile, Logger logger) {
         super(configFile, logger);
@@ -59,9 +68,37 @@ public class ViaBackwardsConfig extends Config implements com.viaversion.viaback
         handlePingsAsInvAcknowledgements = getBoolean("handle-pings-as-inv-acknowledgements", false);
         bedrockAtY0 = getBoolean("bedrock-at-y-0", false);
         sculkShriekersToCryingObsidian = getBoolean("sculk-shriekers-to-crying-obsidian", false);
+        scaffoldingToWater = getBoolean("scaffolding-to-water", false);
         mapDarknessEffect = getBoolean("map-darkness-effect", true);
         mapCustomModelData = getBoolean("map-custom-model-data", true);
+        mapDisplayEntities = getBoolean("map-display-entities", true);
         suppressEmulationWarnings = getBoolean("suppress-emulation-warnings", false);
+        dialogsViaChests = getBoolean("dialogs-via-chests", true);
+        dialogStyleConfig = loadDialogStyleConfig(getSection("dialog-style"));
+        codeOfConductAsDialog = getBoolean("code-of-conduct-as-dialog", true);
+        passOriginalItemNameToResourcePacks = getBoolean("pass-original-item-name-to-resource-packs", true);
+    }
+
+    private DialogStyleConfig loadDialogStyleConfig(final ConfigSection section) {
+        return new DialogStyleConfig(
+            getString(section, "page-navigation-title", "&9&lPage navigation"),
+            getString(section, "page-navigation-next", "&9Left click: &6Go to next page"),
+            getString(section, "page-navigation-previous", "&9Right click: &6Go to previous page"),
+            getString(section, "increase-value", "&9Left click: &6Increase value by %s"),
+            getString(section, "decrease-value", "&9Right click: &6Decrease value by %s"),
+            getString(section, "value-range", "&7(Value between &a%s &7and &a%s&7)"),
+            getString(section, "next-option", "&9Left click: &6Go to next option"),
+            getString(section, "previous-option", "&9Right click: &6Go to previous option"),
+            getString(section, "current-value", "&7Current value: &a%s"),
+            getString(section, "edit-value", "&9Left click: &6Edit text"),
+            getString(section, "set-text", "&9Left click/close: &6Set text"),
+            getString(section, "close", "&9Left click: &6Close"),
+            getString(section, "toggle-value", "&9Left click: &6Toggle value")
+        );
+    }
+
+    protected String getString(final ConfigSection section, final String key, final String def) {
+        return ChatColorUtil.translateAlternateColorCodes(section.getString(key, def));
     }
 
     @Override
@@ -104,6 +141,11 @@ public class ViaBackwardsConfig extends Config implements com.viaversion.viaback
         return sculkShriekersToCryingObsidian;
     }
 
+    @Override
+    public boolean scaffoldingToWater() {
+        return scaffoldingToWater;
+    }
+
     @Override
     public boolean mapDarknessEffect() {
         return mapDarknessEffect;
@@ -114,11 +156,36 @@ public class ViaBackwardsConfig extends Config implements com.viaversion.viaback
         return mapCustomModelData;
     }
 
+    @Override
+    public boolean mapDisplayEntities() {
+        return mapDisplayEntities;
+    }
+
     @Override
     public boolean suppressEmulationWarnings() {
         return suppressEmulationWarnings;
     }
 
+    @Override
+    public boolean dialogsViaChests() {
+        return dialogsViaChests;
+    }
+
+    @Override
+    public DialogStyleConfig dialogStyleConfig() {
+        return dialogStyleConfig;
+    }
+
+    @Override
+    public boolean codeOfConductAsDialog() {
+        return codeOfConductAsDialog;
+    }
+
+    @Override
+    public boolean passOriginalItemNameToResourcePacks() {
+        return passOriginalItemNameToResourcePacks;
+    }
+
     @Override
     public URL getDefaultConfigURL() {
         return getClass().getClassLoader().getResource("assets/viabackwards/config.yml");

common/src/main/java/com/viaversion/viabackwards/ViaBackwardsPlatformImpl.java

@@ -0,0 +1,53 @@
+/*
+ * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
+ * 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.viabackwards;
+
+import com.viaversion.viabackwards.api.ViaBackwardsPlatform;
+import com.viaversion.viaversion.api.Via;
+import java.io.File;
+import java.util.logging.Logger;
+
+public class ViaBackwardsPlatformImpl implements ViaBackwardsPlatform {
+
+    private final Logger logger;
+
+    public ViaBackwardsPlatformImpl() {
+        logger = Via.getPlatform().createLogger("ViaBackwards");
+        init(new File(getDataFolder(), "viabackwards.yml"));
+        enable();
+    }
+
+    @Override
+    public Logger getLogger() {
+        return logger;
+    }
+
+    @Override
+    public void disable() {
+    }
+
+    @Override
+    public File getDataFolder() {
+        return Via.getPlatform().getDataFolder();
+    }
+
+    @Override
+    public boolean isOutdated() {
+        return false;
+    }
+}

common/src/main/java/com/viaversion/viabackwards/api/BackwardsProtocol.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -18,17 +18,20 @@
 package com.viaversion.viabackwards.api;
 
 import com.viaversion.viabackwards.api.data.BackwardsMappingData;
-import com.viaversion.viabackwards.api.rewriters.text.TranslatableRewriter;
-import com.viaversion.viaversion.api.Via;
+import com.viaversion.viabackwards.api.rewriters.BackwardsRegistryRewriter;
+import com.viaversion.viabackwards.protocol.registration.BackwardsRegistrations;
+import com.viaversion.viabackwards.utils.BackwardsProtocolLogger;
 import com.viaversion.viaversion.api.protocol.AbstractProtocol;
 import com.viaversion.viaversion.api.protocol.Protocol;
 import com.viaversion.viaversion.api.protocol.packet.ClientboundPacketType;
 import com.viaversion.viaversion.api.protocol.packet.ServerboundPacketType;
+import com.viaversion.viaversion.util.ProtocolLogger;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
 public abstract class BackwardsProtocol<CU extends ClientboundPacketType, CM extends ClientboundPacketType, SM extends ServerboundPacketType, SU extends ServerboundPacketType>
     extends AbstractProtocol<CU, CM, SM, SU> {
 
+    @Deprecated
     protected BackwardsProtocol() {
     }
 
@@ -37,36 +40,29 @@ public abstract class BackwardsProtocol<CU extends ClientboundPacketType, CM ext
         super(oldClientboundPacketEnum, clientboundPacketEnum, oldServerboundPacketEnum, serverboundPacketEnum);
     }
 
-    /**
-     * Waits for the given protocol to be loaded to then asynchronously execute the runnable for this protocol.
-     */
-    protected void executeAsyncAfterLoaded(Class<? extends Protocol> protocolClass, Runnable runnable) {
-        Via.getManager().getProtocolManager().addMappingLoaderFuture(getClass(), protocolClass, runnable);
+    @Override
+    protected void applySharedRegistrations() {
+        super.applySharedRegistrations();
+        BackwardsRegistrations.registrations().applyMatching(this);
     }
 
     @Override
-    protected void registerPackets() {
-        super.registerPackets();
-
-        final BackwardsMappingData mappingData = getMappingData();
-        if (mappingData != null && mappingData.getViaVersionProtocolClass() != null) {
-            executeAsyncAfterLoaded(mappingData.getViaVersionProtocolClass(), this::loadMappingData);
-        }
+    protected ProtocolLogger createLogger() {
+        return new BackwardsProtocolLogger(getClass());
     }
 
     @Override
-    public boolean hasMappingDataToLoad() {
-        // Manually load them later, since they depend on VV's mappings
-        return false;
+    public @Nullable Class<? extends Protocol<?, ?, ?, ?>> dependsOn() {
+        return getMappingData() != null ? getMappingData().getViaVersionProtocolClass() : null;
     }
 
     @Override
-    public @Nullable BackwardsMappingData getMappingData() { // Change return type to BackwardsMappings
+    public @Nullable BackwardsMappingData getMappingData() {
         return null;
     }
 
     @Override
-    public @Nullable TranslatableRewriter getComponentRewriter() {
+    public @Nullable BackwardsRegistryRewriter getRegistryDataRewriter() {
         return null;
     }
 }

common/src/main/java/com/viaversion/viabackwards/api/DialogStyleConfig.java

@@ -0,0 +1,25 @@
+/*
+ * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
+ * 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.viabackwards.api;
+
+public record DialogStyleConfig(String pageNavigationTitle, String pageNavigationNext, String pageNavigationPrevious,
+                                String increaseValue, String decreaseValue, String valueRange, String nextOption,
+                                String previousOption, String currentValue, String editValue, String setText,
+                                String close, String toggleValue) {
+
+}

common/src/main/java/com/viaversion/viabackwards/api/ViaBackwardsConfig.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -78,6 +78,13 @@ public interface ViaBackwardsConfig extends Config {
      */
     boolean sculkShriekerToCryingObsidian();
 
+    /**
+     * Shows scaffolding as water for 1.13.2 clients on 1.14+ servers. This fixes collision issues.
+     *
+     * @return true if enabled
+     */
+    boolean scaffoldingToWater();
+
     /**
      * Maps the darkness effect to blindness for 1.18.2 clients on 1.19+ servers.
      *
@@ -92,10 +99,47 @@ public interface ViaBackwardsConfig extends Config {
      */
     boolean mapCustomModelData();
 
+    /**
+     * If enabled, 1.19.3 clients will receive display entities as armor stands with custom entity data on 1.19.4+ servers.
+     *
+     * @return true if enabled
+     */
+    boolean mapDisplayEntities();
+
     /**
      * Suppresses warnings of missing emulations for certain features that are not supported (e.g. world height in 1.17+).
      *
      * @return true if enabled
      */
     boolean suppressEmulationWarnings();
+
+    /**
+     * If enabled, dialogs will be shown via chest inventories for 1.21.5 clients on 1.21.6+ servers.
+     *
+     * @return true if enabled
+     */
+    boolean dialogsViaChests();
+
+    /**
+     * Returns the dialog style configuration.
+     *
+     * @return the dialog style configuration
+     */
+    DialogStyleConfig dialogStyleConfig();
+
+    /**
+     * If true, the code of conduct will be displayed as a dialog for 1.21.7 clients on 1.21.9+ servers.
+     *
+     * @return true if enabled
+     */
+    boolean codeOfConductAsDialog();
+
+    /**
+     * Injects the original vanilla 1.21.4+ item name into custom_model_data strings for resource packs.
+     * Disable if your server creates custom items using modern items as their base.
+     * Tip: For server custom items, base them on items in the game before 1.21.4 (e.g. saddle) to ensure compatibility.
+     *
+     * @return true if enabled
+     */
+    boolean passOriginalItemNameToResourcePacks();
 }

common/src/main/java/com/viaversion/viabackwards/api/ViaBackwardsPlatform.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -21,47 +21,56 @@ package com.viaversion.viabackwards.api;
 import com.viaversion.viabackwards.ViaBackwards;
 import com.viaversion.viabackwards.ViaBackwardsConfig;
 import com.viaversion.viabackwards.api.data.TranslatableMappings;
-import com.viaversion.viabackwards.protocol.v1_11to1_10.Protocol1_11To1_10;
-import com.viaversion.viabackwards.protocol.v1_12to1_11_1.Protocol1_12To1_11_1;
+import com.viaversion.viabackwards.protocol.registration.BackwardsRegistrations;
+import com.viaversion.viabackwards.protocol.v1_10to1_9_3.Protocol1_10To1_9_3;
 import com.viaversion.viabackwards.protocol.v1_11_1to1_11.Protocol1_11_1To1_11;
-import com.viaversion.viabackwards.protocol.v1_12_2to1_12_1.Protocol1_12_2To1_12_1;
-import com.viaversion.viabackwards.protocol.v1_13to1_12_2.Protocol1_13To1_12_2;
+import com.viaversion.viabackwards.protocol.v1_11to1_10.Protocol1_11To1_10;
 import com.viaversion.viabackwards.protocol.v1_12_1to1_12.Protocol1_12_1To1_12;
-import com.viaversion.viabackwards.protocol.v1_13_2to1_13_1.Protocol1_13_2To1_13_1;
-import com.viaversion.viabackwards.protocol.v1_14to1_13_2.Protocol1_14To1_13_2;
+import com.viaversion.viabackwards.protocol.v1_12_2to1_12_1.Protocol1_12_2To1_12_1;
+import com.viaversion.viabackwards.protocol.v1_12to1_11_1.Protocol1_12To1_11_1;
 import com.viaversion.viabackwards.protocol.v1_13_1to1_13.Protocol1_13_1To1_13;
+import com.viaversion.viabackwards.protocol.v1_13_2to1_13_1.Protocol1_13_2To1_13_1;
+import com.viaversion.viabackwards.protocol.v1_13to1_12_2.Protocol1_13To1_12_2;
+import com.viaversion.viabackwards.protocol.v1_14_1to1_14.Protocol1_14_1To1_14;
 import com.viaversion.viabackwards.protocol.v1_14_2to1_14_1.Protocol1_14_2To1_14_1;
 import com.viaversion.viabackwards.protocol.v1_14_3to1_14_2.Protocol1_14_3To1_14_2;
 import com.viaversion.viabackwards.protocol.v1_14_4to1_14_3.Protocol1_14_4To1_14_3;
-import com.viaversion.viabackwards.protocol.v1_15to1_14_4.Protocol1_15To1_14_4;
-import com.viaversion.viabackwards.protocol.v1_14_1to1_14.Protocol1_14_1To1_14;
-import com.viaversion.viabackwards.protocol.v1_15_2to1_15_1.Protocol1_15_2To1_15_1;
-import com.viaversion.viabackwards.protocol.v1_16to1_15_2.Protocol1_16To1_15_2;
+import com.viaversion.viabackwards.protocol.v1_14to1_13_2.Protocol1_14To1_13_2;
 import com.viaversion.viabackwards.protocol.v1_15_1to1_15.Protocol1_15_1To1_15;
+import com.viaversion.viabackwards.protocol.v1_15_2to1_15_1.Protocol1_15_2To1_15_1;
+import com.viaversion.viabackwards.protocol.v1_15to1_14_4.Protocol1_15To1_14_4;
+import com.viaversion.viabackwards.protocol.v1_16_1to1_16.Protocol1_16_1To1_16;
 import com.viaversion.viabackwards.protocol.v1_16_2to1_16_1.Protocol1_16_2To1_16_1;
 import com.viaversion.viabackwards.protocol.v1_16_3to1_16_2.Protocol1_16_3To1_16_2;
 import com.viaversion.viabackwards.protocol.v1_16_4to1_16_3.Protocol1_16_4To1_16_3;
-import com.viaversion.viabackwards.protocol.v1_17to1_16_4.Protocol1_17To1_16_4;
-import com.viaversion.viabackwards.protocol.v1_16_1to1_16.Protocol1_16_1To1_16;
-import com.viaversion.viabackwards.protocol.v1_18to1_17_1.Protocol1_18To1_17_1;
+import com.viaversion.viabackwards.protocol.v1_16to1_15_2.Protocol1_16To1_15_2;
 import com.viaversion.viabackwards.protocol.v1_17_1to1_17.Protocol1_17_1To1_17;
-import com.viaversion.viabackwards.protocol.v1_19to1_18_2.Protocol1_19To1_18_2;
+import com.viaversion.viabackwards.protocol.v1_17to1_16_4.Protocol1_17To1_16_4;
 import com.viaversion.viabackwards.protocol.v1_18_2to1_18.Protocol1_18_2To1_18;
+import com.viaversion.viabackwards.protocol.v1_18to1_17_1.Protocol1_18To1_17_1;
+import com.viaversion.viabackwards.protocol.v1_19_1to1_19.Protocol1_19_1To1_19;
 import com.viaversion.viabackwards.protocol.v1_19_3to1_19_1.Protocol1_19_3To1_19_1;
 import com.viaversion.viabackwards.protocol.v1_19_4to1_19_3.Protocol1_19_4To1_19_3;
-import com.viaversion.viabackwards.protocol.v1_21_4to1_21_2.Protocol1_21_4To1_21_2;
-import com.viaversion.viabackwards.protocol.v1_20to1_19_4.Protocol1_20To1_19_4;
-import com.viaversion.viabackwards.protocol.v1_19_1to1_19.Protocol1_19_1To1_19;
+import com.viaversion.viabackwards.protocol.v1_19to1_18_2.Protocol1_19To1_18_2;
+import com.viaversion.viabackwards.protocol.v1_20_2to1_20.Protocol1_20_2To1_20;
 import com.viaversion.viabackwards.protocol.v1_20_3to1_20_2.Protocol1_20_3To1_20_2;
 import com.viaversion.viabackwards.protocol.v1_20_5to1_20_3.Protocol1_20_5To1_20_3;
-import com.viaversion.viabackwards.protocol.v1_20_2to1_20.Protocol1_20_2To1_20;
+import com.viaversion.viabackwards.protocol.v1_20to1_19_4.Protocol1_20To1_19_4;
+import com.viaversion.viabackwards.protocol.v1_21_11to1_21_9.Protocol1_21_11To1_21_9;
 import com.viaversion.viabackwards.protocol.v1_21_2to1_21.Protocol1_21_2To1_21;
 import com.viaversion.viabackwards.protocol.v1_21_2to1_21.task.PlayerPacketsTickTask;
+import com.viaversion.viabackwards.protocol.v1_21_4to1_21_2.Protocol1_21_4To1_21_2;
 import com.viaversion.viabackwards.protocol.v1_21_5to1_21_4.Protocol1_21_5To1_21_4;
+import com.viaversion.viabackwards.protocol.v1_21_6to1_21_5.Protocol1_21_6To1_21_5;
+import com.viaversion.viabackwards.protocol.v1_21_6to1_21_5.task.ChestDialogViewTask;
+import com.viaversion.viabackwards.protocol.v1_21_7to1_21_6.Protocol1_21_7To1_21_6;
+import com.viaversion.viabackwards.protocol.v1_21_9to1_21_7.Protocol1_21_9To1_21_7;
 import com.viaversion.viabackwards.protocol.v1_21to1_20_5.Protocol1_21To1_20_5;
-import com.viaversion.viabackwards.protocol.v1_9_3to1_9_1.Protocol1_9_3To1_9_1;
-import com.viaversion.viabackwards.protocol.v1_10to1_9_3.Protocol1_10To1_9_3;
 import com.viaversion.viabackwards.protocol.v1_9_1to1_9.Protocol1_9_1To1_9;
+import com.viaversion.viabackwards.protocol.v1_9_3to1_9_1.Protocol1_9_3To1_9_1;
+import com.viaversion.viabackwards.protocol.v26_1to1_21_11.Protocol26_1To1_21_11;
+import com.viaversion.viabackwards.protocol.v26_2to26_1.Protocol26_2To26_1;
+import com.viaversion.viabackwards.protocol.v26_3to26_2.Protocol26_3To26_2;
 import com.viaversion.viabackwards.utils.VersionInfo;
 import com.viaversion.viaversion.api.Via;
 import com.viaversion.viaversion.api.protocol.ProtocolManager;
@@ -73,13 +82,16 @@ import java.util.logging.Logger;
 
 public interface ViaBackwardsPlatform {
 
-    String MINIMUM_VV_VERSION = "5.3.2";
+    String MINIMUM_VV_VERSION = "5.12.2";
+
+    default void init(final File configFile) {
+        init(new ViaBackwardsConfig(configFile, getLogger()));
+    }
 
     /**
      * Initialize ViaBackwards.
      */
-    default void init(final File configFile) {
-        ViaBackwardsConfig config = new ViaBackwardsConfig(configFile, getLogger());
+    default void init(final com.viaversion.viabackwards.api.ViaBackwardsConfig config) {
         config.reload();
         Via.getManager().getConfigurationProvider().register(config);
 
@@ -96,6 +108,8 @@ public interface ViaBackwardsPlatform {
         TranslatableMappings.loadTranslatables();
 
         getLogger().info("Registering protocols...");
+        BackwardsRegistrations.apply();
+
         final ProtocolManager protocolManager = Via.getManager().getProtocolManager();
         protocolManager.registerProtocol(new Protocol1_9_1To1_9(), ProtocolVersion.v1_9, ProtocolVersion.v1_9_1);
         protocolManager.registerProtocol(new Protocol1_9_3To1_9_1(), Arrays.asList(ProtocolVersion.v1_9_1, ProtocolVersion.v1_9_2), ProtocolVersion.v1_9_3);
@@ -148,6 +162,15 @@ public interface ViaBackwardsPlatform {
         protocolManager.registerProtocol(new Protocol1_21_2To1_21(), ProtocolVersion.v1_21, ProtocolVersion.v1_21_2);
         protocolManager.registerProtocol(new Protocol1_21_4To1_21_2(), ProtocolVersion.v1_21_2, ProtocolVersion.v1_21_4);
         protocolManager.registerProtocol(new Protocol1_21_5To1_21_4(), ProtocolVersion.v1_21_4, ProtocolVersion.v1_21_5);
+
+        protocolManager.registerProtocol(new Protocol1_21_6To1_21_5(), ProtocolVersion.v1_21_5, ProtocolVersion.v1_21_6);
+        protocolManager.registerProtocol(new Protocol1_21_7To1_21_6(), ProtocolVersion.v1_21_6, ProtocolVersion.v1_21_7);
+        protocolManager.registerProtocol(new Protocol1_21_9To1_21_7(), ProtocolVersion.v1_21_7, ProtocolVersion.v1_21_9);
+        protocolManager.registerProtocol(new Protocol1_21_11To1_21_9(), ProtocolVersion.v1_21_9, ProtocolVersion.v1_21_11);
+
+        protocolManager.registerProtocol(new Protocol26_1To1_21_11(), ProtocolVersion.v1_21_11, ProtocolVersion.v26_1);
+        protocolManager.registerProtocol(new Protocol26_2To26_1(), ProtocolVersion.v26_1, ProtocolVersion.v26_2);
+        protocolManager.registerProtocol(new Protocol26_3To26_2(), ProtocolVersion.v26_2, ProtocolVersion.v26_3);
     }
 
     default void enable() {
@@ -155,6 +178,10 @@ public interface ViaBackwardsPlatform {
         if (protocolVersion.newerThanOrEqualTo(ProtocolVersion.v1_21_2)) {
             Via.getPlatform().runRepeatingSync(new PlayerPacketsTickTask(), 1L);
         }
+
+        if (protocolVersion.newerThanOrEqualTo(ProtocolVersion.v1_21_6)) {
+            Via.getPlatform().runRepeatingSync(new ChestDialogViewTask(), 20L);
+        }
     }
 
     /**

common/src/main/java/com/viaversion/viabackwards/api/data/BackwardsMappingData.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -18,6 +18,10 @@
 package com.viaversion.viabackwards.api.data;
 
 import com.google.common.base.Preconditions;
+import com.viaversion.nbt.tag.CompoundTag;
+import com.viaversion.nbt.tag.NumberTag;
+import com.viaversion.nbt.tag.StringTag;
+import com.viaversion.nbt.tag.Tag;
 import com.viaversion.viabackwards.ViaBackwards;
 import com.viaversion.viabackwards.api.BackwardsProtocol;
 import com.viaversion.viaversion.api.Via;
@@ -30,12 +34,7 @@ import com.viaversion.viaversion.api.protocol.Protocol;
 import com.viaversion.viaversion.libs.fastutil.ints.Int2ObjectArrayMap;
 import com.viaversion.viaversion.libs.fastutil.ints.Int2ObjectMap;
 import com.viaversion.viaversion.libs.fastutil.ints.Int2ObjectOpenHashMap;
-import com.viaversion.nbt.tag.CompoundTag;
-import com.viaversion.nbt.tag.NumberTag;
-import com.viaversion.nbt.tag.StringTag;
-import com.viaversion.nbt.tag.Tag;
 import com.viaversion.viaversion.util.Key;
-import java.util.HashMap;
 import java.util.Map;
 import java.util.logging.Level;
 import java.util.logging.Logger;
@@ -45,8 +44,6 @@ public class BackwardsMappingData extends MappingDataBase {
 
     private final Class<? extends Protocol<?, ?, ?, ?>> vvProtocolClass;
     protected Int2ObjectMap<MappedItem> backwardsItemMappings;
-    private Map<String, String> backwardsSoundMappings;
-    private Map<String, String> entityNames;
     private Int2ObjectMap<String> enchantmentNames;
 
     public BackwardsMappingData(final String unmappedVersion, final String mappedVersion) {
@@ -61,43 +58,23 @@ public class BackwardsMappingData extends MappingDataBase {
 
     @Override
     protected void loadExtras(final CompoundTag data) {
-        final CompoundTag itemNames = data.getCompoundTag("itemnames");
-        if (itemNames != null) {
+        final CompoundTag itemCustomModelDatas = data.getCompoundTag("custom_model_data");
+        if (itemCustomModelDatas != null) {
             Preconditions.checkNotNull(itemMappings);
-            backwardsItemMappings = new Int2ObjectOpenHashMap<>(itemNames.size());
-
-            final CompoundTag extraItemData = data.getCompoundTag("itemdata");
-            for (final Map.Entry<String, Tag> entry : itemNames.entrySet()) {
-                final StringTag name = (StringTag) entry.getValue();
-                final int id = Integer.parseInt(entry.getKey());
-                Integer customModelData = null;
-                if (extraItemData != null && extraItemData.contains(entry.getKey())) {
-                    final CompoundTag entryTag = extraItemData.getCompoundTag(entry.getKey());
-                    final NumberTag customModelDataTag = entryTag.getNumberTag("custom_model_data");
-                    customModelData = customModelDataTag != null ? customModelDataTag.asInt() : null;
-                }
-
-                backwardsItemMappings.put(id, new MappedItem(getNewItemId(id), name.getValue(), customModelData));
-            }
+            backwardsItemMappings = new Int2ObjectOpenHashMap<>(itemCustomModelDatas.size());
+            loadBackwardsItemMappings(itemCustomModelDatas);
         }
-
-        this.entityNames = loadNameByStringMappings(data, "entitynames");
         this.enchantmentNames = loadNameByIdMappings(data, "enchantmentnames");
-        this.backwardsSoundMappings = loadNameByStringMappings(data, "soundnames");
     }
 
-    private @Nullable Map<String, String> loadNameByStringMappings(final CompoundTag data, final String key) {
-        final CompoundTag nameMappings = data.getCompoundTag(key);
-        if (nameMappings == null) {
-            return null;
+    protected void loadBackwardsItemMappings(final CompoundTag itemCustomModelDatas) {
+        for (final Map.Entry<String, Tag> entry : itemCustomModelDatas.entrySet()) {
+            final int id = Integer.parseInt(entry.getKey());
+            final int customModelData = ((NumberTag) entry.getValue()).asInt();
+            final String identifier = getFullItemMappings().identifier(id);
+            final String fallbackName = unmappedVersion + " " + nameFromIdentifier(identifier);
+            backwardsItemMappings.put(id, new MappedItem(getNewItemId(id), identifier, fallbackName, customModelData));
         }
-
-        final Map<String, String> map = new HashMap<>(nameMappings.size());
-        for (final Map.Entry<String, Tag> entry : nameMappings.entrySet()) {
-            final StringTag mappedTag = (StringTag) entry.getValue();
-            map.put(entry.getKey(), mappedTag.getValue());
-        }
-        return map;
     }
 
     private @Nullable Int2ObjectMap<String> loadNameByIdMappings(final CompoundTag data, final String key) {
@@ -161,18 +138,7 @@ public class BackwardsMappingData extends MappingDataBase {
     }
 
     public @Nullable String getMappedNamedSound(final String id) {
-        if (backwardsSoundMappings == null) {
-            return null;
-        }
-        return backwardsSoundMappings.get(Key.stripMinecraftNamespace(id));
-    }
-
-    public @Nullable String mappedEntityName(final String entityName) {
-        if (entityNames == null) {
-            getLogger().log(Level.SEVERE, "No entity mappings found when requesting them for " + entityName, new RuntimeException());
-            return null;
-        }
-        return entityNames.get(entityName);
+        return getFullSoundMappings().mappedIdentifier(id);
     }
 
     public @Nullable String mappedEnchantmentName(final int enchantmentId) {
@@ -187,10 +153,6 @@ public class BackwardsMappingData extends MappingDataBase {
         return backwardsItemMappings;
     }
 
-    public @Nullable Map<String, String> getBackwardsSoundMappings() {
-        return backwardsSoundMappings;
-    }
-
     public @Nullable Class<? extends Protocol<?, ?, ?, ?>> getViaVersionProtocolClass() {
         return vvProtocolClass;
     }
@@ -204,4 +166,12 @@ public class BackwardsMappingData extends MappingDataBase {
     protected @Nullable CompoundTag readMappingsFile(final String name) {
         return BackwardsMappingDataLoader.INSTANCE.loadNBTFromDir(name);
     }
+
+    public static String nameFromIdentifier(final String identifier) {
+        final StringBuilder result = new StringBuilder();
+        for (final String split : Key.stripMinecraftNamespace(identifier).split("_")) {
+            result.append(' ').append(Character.toUpperCase(split.charAt(0))).append(split.substring(1));
+        }
+        return result.substring(1);
+    }
 }

common/src/main/java/com/viaversion/viabackwards/api/data/BackwardsMappingDataLoader.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -17,10 +17,10 @@
  */
 package com.viaversion.viabackwards.api.data;
 
-import com.viaversion.viabackwards.ViaBackwards;
-import com.viaversion.viaversion.api.data.MappingDataLoader;
 import com.viaversion.nbt.tag.CompoundTag;
 import com.viaversion.nbt.tag.Tag;
+import com.viaversion.viabackwards.ViaBackwards;
+import com.viaversion.viaversion.api.data.MappingDataLoader;
 import java.io.File;
 import java.io.IOException;
 import java.util.Map;

common/src/main/java/com/viaversion/viabackwards/api/data/ItemMappings.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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

common/src/main/java/com/viaversion/viabackwards/api/data/MappedItem.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -17,26 +17,43 @@
  */
 package com.viaversion.viabackwards.api.data;
 
+import com.viaversion.nbt.tag.CompoundTag;
 import com.viaversion.nbt.tag.Tag;
-import com.viaversion.viaversion.util.ComponentUtil;
-import org.checkerframework.checker.nullness.qual.Nullable;
+import com.viaversion.viaversion.libs.gson.JsonPrimitive;
+import com.viaversion.viaversion.util.Key;
 
 public class MappedItem {
 
     private final int id;
     private final String jsonName;
     private final Tag tagName;
-    private final Integer customModelData;
+    private final int customModelData;
 
-    public MappedItem(final int id, final String name) {
-        this(id, name, null);
+    public MappedItem(final int id, String identifier, final String fallbackName, final int customModelData) {
+        this.id = id;
+        identifier = Key.stripMinecraftNamespace(identifier);
+        final String translateKey = "vb.item." + identifier;
+        this.jsonName = itemJsonName(fallbackName);
+        this.tagName = itemTagName(translateKey, fallbackName);
+        this.customModelData = customModelData;
     }
 
-    public MappedItem(final int id, final String name, @Nullable final Integer customModelData) {
-        this.id = id;
-        this.jsonName = ComponentUtil.legacyToJsonString("§f" + name, true);
-        this.tagName = ComponentUtil.jsonStringToTag(jsonName);
-        this.customModelData = customModelData;
+    // Make explicitly non-italic and white to override default item formatting.
+    // Properly parsing is expensive...
+    private static String itemJsonName(final String name) {
+        return """
+            {"italic":false,"color":"white","text":%s}
+            """.formatted(new JsonPrimitive(name).toString());
+    }
+
+    private static Tag itemTagName(final String translateKey, final String fallbackName) {
+        // Proper translate with fallback field (valid for 1.19.4+ clients)
+        final CompoundTag tag = new CompoundTag();
+        tag.putString("color", "white");
+        tag.putString("translate", translateKey);
+        tag.putString("fallback", fallbackName);
+        tag.putBoolean("italic", false);
+        return tag;
     }
 
     public int id() {
@@ -48,10 +65,10 @@ public class MappedItem {
     }
 
     public Tag tagName() {
-        return tagName;
+        return tagName.copy();
     }
 
-    public @Nullable Integer customModelData() {
+    public int customModelData() {
         return customModelData;
     }
 }

common/src/main/java/com/viaversion/viabackwards/api/data/MappedLegacyBlockItem.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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

common/src/main/java/com/viaversion/viabackwards/api/data/TranslatableMappings.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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

common/src/main/java/com/viaversion/viabackwards/api/entities/EntityScaleData.java

@@ -0,0 +1,48 @@
+/*
+ * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
+ * 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.viabackwards.api.entities;
+
+
+import com.viaversion.viaversion.api.connection.StorableObject;
+import com.viaversion.viaversion.api.data.entity.TrackedEntity;
+
+/**
+ * Storage object used within {@link TrackedEntity} to track the scaling state of an entity.
+ * This ensures that scale updates are only sent when the calculated scale actually changes.
+ */
+public final class EntityScaleData implements StorableObject {
+
+    private boolean isBaby;
+    private float scale = 1.0f;
+
+    public boolean isBaby() {
+        return isBaby;
+    }
+
+    public void setBaby(boolean baby) {
+        this.isBaby = baby;
+    }
+
+    public float scale() {
+        return scale;
+    }
+
+    public void setScale(float scale) {
+        this.scale = scale;
+    }
+}

common/src/main/java/com/viaversion/viabackwards/api/entities/EntityScaleHelper.java

@@ -0,0 +1,102 @@
+/*
+ * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
+ * 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.viabackwards.api.entities;
+
+
+import com.google.common.base.Preconditions;
+import com.viaversion.viaversion.api.data.FullMappings;
+import com.viaversion.viaversion.api.minecraft.entities.EntityType;
+import com.viaversion.viaversion.api.minecraft.entitydata.EntityData;
+import com.viaversion.viaversion.api.protocol.Protocol;
+import com.viaversion.viaversion.api.protocol.packet.ClientboundPacketType;
+import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
+import com.viaversion.viaversion.api.type.Types;
+import com.viaversion.viaversion.rewriter.EntityRewriter;
+import com.viaversion.viaversion.rewriter.entitydata.EntityDataHandlerEvent;
+
+/**
+ * A helper for injecting entity scaling on older clients.
+ * This helper listens for the baby entity data flag and sends an UPDATE_ATTRIBUTES packet
+ * to scale the entity, since older clients might not support the newer entity variants natively.
+ */
+public class EntityScaleHelper {
+
+    private final ClientboundPacketType updateAttributesPacket;
+    private final EntityRewriter<?, ?> rewriter;
+
+    /**
+     * Constructs a new entity scale helper.
+     *
+     * @param rewriter               entity rewriter
+     * @param updateAttributesPacket UPDATE_ATTRIBUTES packet of the mapped protocol
+     * @param <CM>                   mapped clientbound packet type
+     */
+    public <CM extends ClientboundPacketType, P extends Protocol<?, CM, ?, ?>> EntityScaleHelper(final EntityRewriter<?, P> rewriter, final CM updateAttributesPacket) {
+        this.rewriter = rewriter;
+        this.updateAttributesPacket = updateAttributesPacket;
+    }
+
+    /**
+     * Registers a scaling factor for a specific baby entity type.
+     *
+     * @param type            entity type that requires scaling when it is a baby
+     * @param babyScaleFactor multiplier to apply to the minecraft:scale attribute when it is a baby
+     * @param babyIndex       entity data index for the baby property in this specific protocol
+     */
+    public void addBabyScale(final EntityType type, final float babyScaleFactor, final int babyIndex) {
+        rewriter.filter().type(type).index(babyIndex).handler(((event, data) -> trackAndSend(event, data, babyScaleFactor)));
+    }
+
+    /**
+     * Checks the entity data, tracks the scale state and sends an UPDATE_ATTRIBUTES packet if needed.
+     */
+    public void trackAndSend(final EntityDataHandlerEvent event, final EntityData data, final float babyScaleFactor) {
+        if (event.trackedEntity() == null) {
+            return;
+        }
+
+        EntityScaleData scaleData = event.trackedEntity().get(EntityScaleData.class);
+        if (scaleData == null) {
+            scaleData = new EntityScaleData();
+            event.trackedEntity().put(scaleData);
+        }
+
+        final boolean isBaby = data.value();
+        if (scaleData.isBaby() == isBaby) {
+            return;
+        }
+
+        scaleData.setBaby(isBaby);
+        scaleData.setScale(isBaby ? babyScaleFactor : 1.0f);
+
+        final FullMappings attributeMappings = rewriter.protocol().getMappingData().getAttributeMappings();
+        int attributeId = attributeMappings.mappedId("scale");
+        if (attributeId == -1) {
+            attributeId = attributeMappings.mappedId("generic.scale");
+            Preconditions.checkArgument(attributeId != -1);
+        }
+
+        final PacketWrapper attributesPacket = PacketWrapper.create(updateAttributesPacket, event.user());
+        attributesPacket.write(Types.VAR_INT, event.entityId());
+        attributesPacket.write(Types.VAR_INT, 1); // 1 attribute
+        attributesPacket.write(Types.VAR_INT, attributeId);
+        attributesPacket.write(Types.DOUBLE, (double) scaleData.scale());
+        attributesPacket.write(Types.VAR_INT, 0); // 0 modifiers
+        attributesPacket.send(rewriter.protocol().getClass());
+    }
+}

common/src/main/java/com/viaversion/viabackwards/api/entities/storage/EntityObjectData.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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

common/src/main/java/com/viaversion/viabackwards/api/entities/storage/EntityPositionHandler.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -18,12 +18,10 @@
 package com.viaversion.viabackwards.api.entities.storage;
 
 import com.viaversion.viabackwards.api.rewriters.EntityRewriterBase;
-import com.viaversion.viaversion.api.Via;
 import com.viaversion.viaversion.api.connection.UserConnection;
-import com.viaversion.viaversion.api.data.entity.StoredEntityData;
+import com.viaversion.viaversion.api.data.entity.TrackedEntity;
 import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
 import com.viaversion.viaversion.api.type.Types;
-import com.viaversion.viaversion.util.ProtocolLogger;
 import java.util.function.Supplier;
 
 public class EntityPositionHandler {
@@ -32,7 +30,6 @@ public class EntityPositionHandler {
     private final EntityRewriterBase<?, ?> entityRewriter;
     private final Class<? extends EntityPositionStorage> storageClass;
     private final Supplier<? extends EntityPositionStorage> storageSupplier;
-    private boolean warnedForMissingEntity;
 
     public EntityPositionHandler(EntityRewriterBase<?, ?> entityRewriter,
                                  Class<? extends EntityPositionStorage> storageClass, Supplier<? extends EntityPositionStorage> storageSupplier) {
@@ -47,28 +44,22 @@ public class EntityPositionHandler {
     }
 
     public void cacheEntityPosition(PacketWrapper wrapper, double x, double y, double z, boolean create, boolean relative) {
-        int entityId = wrapper.get(Types.VAR_INT, 0);
-        StoredEntityData storedEntity = entityRewriter.tracker(wrapper.user()).entityData(entityId);
-        if (storedEntity == null) {
-            if (Via.getManager().isDebug()) { // There is too many plugins violating this out there, and reading seems to be hard! :>
-                ProtocolLogger logger = entityRewriter.protocol().getLogger();
-                logger.warning("Stored entity with id " + entityId + " missing at position: " + x + " - " + y + " - " + z + " in " + storageClass.getSimpleName());
-                if (entityId == -1 && x == 0 && y == 0 && z == 0) {
-                    logger.warning("DO NOT REPORT THIS TO VIA, THIS IS A PLUGIN ISSUE");
-                } else if (!warnedForMissingEntity) {
-                    warnedForMissingEntity = true;
-                    logger.warning("This is very likely caused by a plugin sending a teleport packet for an entity outside of the player's range.");
-                }
-            }
+        cacheEntityPosition(wrapper, wrapper.get(Types.VAR_INT, 0), x, y, z, create, relative);
+    }
+
+    public void cacheEntityPosition(PacketWrapper wrapper, int entityId, double x, double y, double z, boolean create, boolean relative) {
+        final TrackedEntity entity = entityRewriter.tracker(wrapper.user()).entity(entityId);
+        if (entity == null) {
+            // Bad plugins
             return;
         }
 
         EntityPositionStorage positionStorage;
         if (create) {
             positionStorage = storageSupplier.get();
-            storedEntity.put(positionStorage);
+            entity.put(positionStorage);
         } else {
-            positionStorage = storedEntity.get(storageClass);
+            positionStorage = entity.get(storageClass);
             if (positionStorage == null) {
                 entityRewriter.protocol().getLogger().warning("Stored entity with id " + entityId + " missing " + storageClass.getSimpleName());
                 return;
@@ -83,9 +74,9 @@ public class EntityPositionHandler {
     }
 
     public EntityPositionStorage getStorage(UserConnection user, int entityId) {
-        StoredEntityData storedEntity = entityRewriter.tracker(user).entityData(entityId);
+        final TrackedEntity entity = entityRewriter.tracker(user).entity(entityId);
         EntityPositionStorage entityStorage;
-        if (storedEntity == null || (entityStorage = storedEntity.get(EntityPositionStorage.class)) == null) {
+        if (entity == null || (entityStorage = entity.get(EntityPositionStorage.class)) == null) {
             entityRewriter.protocol().getLogger().warning("Untracked entity with id " + entityId + " in " + storageClass.getSimpleName());
             return null;
         }

common/src/main/java/com/viaversion/viabackwards/api/entities/storage/EntityPositionStorage.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -17,7 +17,9 @@
  */
 package com.viaversion.viabackwards.api.entities.storage;
 
-public abstract class EntityPositionStorage {
+import com.viaversion.viaversion.api.connection.StorableObject;
+
+public abstract class EntityPositionStorage implements StorableObject {
     private double x;
     private double y;
     private double z;

common/src/main/java/com/viaversion/viabackwards/api/entities/storage/EntityReplacement.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -18,9 +18,11 @@
 
 package com.viaversion.viabackwards.api.entities.storage;
 
-import com.viaversion.viabackwards.api.BackwardsProtocol;
-import com.viaversion.viaversion.api.minecraft.entities.EntityType;
+import com.viaversion.nbt.tag.CompoundTag;
 import com.viaversion.nbt.tag.StringTag;
+import com.viaversion.viabackwards.api.BackwardsProtocol;
+import com.viaversion.viabackwards.api.data.BackwardsMappingData;
+import com.viaversion.viaversion.api.minecraft.entities.EntityType;
 import com.viaversion.viaversion.util.ComponentUtil;
 import java.util.Locale;
 import org.checkerframework.checker.nullness.qual.Nullable;
@@ -30,18 +32,22 @@ public class EntityReplacement {
     private final int id;
     private final int replacementId;
     private final String key;
+    private final String translateKey;
+    private final String fallbackName;
     private ComponentType componentType = ComponentType.NONE;
     private EntityDataCreator defaultData;
 
     public EntityReplacement(BackwardsProtocol<?, ?, ?, ?> protocol, EntityType type, int replacementId) {
-        this(protocol, type.name(), type.getId(), replacementId);
+        this(protocol, type.name().toLowerCase(Locale.ROOT), type.getId(), replacementId);
     }
 
     public EntityReplacement(BackwardsProtocol<?, ?, ?, ?> protocol, String key, int id, int replacementId) {
         this.protocol = protocol;
         this.id = id;
         this.replacementId = replacementId;
-        this.key = key.toLowerCase(Locale.ROOT);
+        this.key = key;
+        this.translateKey = "vb.entity." + key;
+        this.fallbackName = BackwardsMappingData.nameFromIdentifier(this.key);
     }
 
     public EntityReplacement jsonName() {
@@ -73,24 +79,26 @@ public class EntityReplacement {
     }
 
     /**
-     * @return custom mobname, can be either a String or a JsonElement
+     * Returns the custom entity name. Can be either a {@link String}, {@link StringTag} or {@link com.viaversion.viaversion.libs.gson.JsonElement}.
+     *
+     * @return custom entity name
      */
     public @Nullable Object entityName() {
         if (componentType == ComponentType.NONE) {
             return null;
         }
 
-        final String name = protocol.getMappingData().mappedEntityName(key);
-        if (name == null) {
-            return null;
-        }
-
         if (componentType == ComponentType.JSON) {
-            return ComponentUtil.legacyToJson(name);
+            return ComponentUtil.plainToJson(fallbackName); // Pass on as plain, with or without section symbols
         } else if (componentType == ComponentType.TAG) {
-            return new StringTag(name);
+            final CompoundTag tag = new CompoundTag();
+            tag.putString("color", "white");
+            tag.putString("translate", translateKey);
+            tag.putString("fallback", fallbackName);
+            tag.putBoolean("italic", false);
+            return tag;
         }
-        return name;
+        return fallbackName;
     }
 
     public int replacementId() {

common/src/main/java/com/viaversion/viabackwards/api/entities/storage/PlayerPosRotStorage.java

@@ -0,0 +1,57 @@
+/*
+ * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
+ * 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.viabackwards.api.entities.storage;
+
+import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
+import com.viaversion.viaversion.api.type.Types;
+
+public class PlayerPosRotStorage extends PlayerPositionStorage {
+    private float yRot; // yaw
+    private float xRot; // pitch
+
+    public float yRot() {
+        return yRot;
+    }
+
+    public void setYRot(final float yRot) {
+        this.yRot = yRot;
+    }
+
+    public float xRot() {
+        return xRot;
+    }
+
+    public void setXRot(final float xRot) {
+        this.xRot = xRot;
+    }
+
+    public void setRotation(final float yRot, final float xRot) {
+        this.yRot = yRot;
+        this.xRot = xRot;
+    }
+
+    public void setRotFromPacket(final PacketWrapper wrapper) {
+        this.yRot = wrapper.passthrough(Types.FLOAT);
+        this.xRot = wrapper.passthrough(Types.FLOAT);
+    }
+
+    public void setPosRotFromPacket(final PacketWrapper wrapper) {
+        this.setPosFromPacket(wrapper);
+        this.setRotFromPacket(wrapper);
+    }
+}

common/src/main/java/com/viaversion/viabackwards/api/entities/storage/PlayerPositionStorage.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -18,15 +18,14 @@
 package com.viaversion.viabackwards.api.entities.storage;
 
 import com.viaversion.viaversion.api.connection.StorableObject;
+import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
+import com.viaversion.viaversion.api.type.Types;
 
-public abstract class PlayerPositionStorage implements StorableObject {
+public class PlayerPositionStorage implements StorableObject {
     private double x;
     private double y;
     private double z;
 
-    protected PlayerPositionStorage() {
-    }
-
     public double x() {
         return x;
     }
@@ -57,6 +56,12 @@ public abstract class PlayerPositionStorage implements StorableObject {
         this.z = z;
     }
 
+    public void setPosFromPacket(PacketWrapper wrapper) {
+        this.x = wrapper.passthrough(Types.DOUBLE);
+        this.y = wrapper.passthrough(Types.DOUBLE);
+        this.z = wrapper.passthrough(Types.DOUBLE);
+    }
+
     public void addRelativePosition(double relX, double relY, double relZ) {
         this.x += relX;
         this.y += relY;

common/src/main/java/com/viaversion/viabackwards/api/entities/storage/WrappedEntityData.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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

common/src/main/java/com/viaversion/viabackwards/api/rewriters/BackwardsFullStructuredItemRewriter.java

@@ -0,0 +1,81 @@
+/*
+ * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
+ * 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.viabackwards.api.rewriters;
+
+import com.viaversion.nbt.tag.CompoundTag;
+import com.viaversion.nbt.tag.Tag;
+import com.viaversion.viabackwards.api.BackwardsProtocol;
+import com.viaversion.viaversion.api.connection.ProtocolInfo;
+import com.viaversion.viaversion.api.connection.UserConnection;
+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.protocol.packet.ClientboundPacketType;
+import com.viaversion.viaversion.api.protocol.packet.ServerboundPacketType;
+import com.viaversion.viaversion.api.protocol.version.ProtocolVersion;
+
+// 1.20.5-1.21.4
+public class BackwardsFullStructuredItemRewriter<C extends ClientboundPacketType, S extends ServerboundPacketType,
+    T extends BackwardsProtocol<C, ?, ?, S>> extends BackwardsStructuredItemRewriter<C, S, T> {
+
+    public BackwardsFullStructuredItemRewriter(final T protocol) {
+        super(protocol);
+    }
+
+    @Override
+    public Item handleItemToServer(final UserConnection connection, final Item item) {
+        if (Item.isEmpty(item)) {
+            return item;
+        }
+
+        final ProtocolInfo protocolInfo = connection.getProtocolInfo();
+        if (protocolInfo.serverProtocolVersion().newerThanOrEqualTo(ProtocolVersion.v1_21_5)
+            && !protocol.getEntityRewriter().tracker(connection).canInstaBuild()) {
+            // We don't actually need anything but the amount, id, and hashes.
+            // Just pass it on without deeper handling, only leaving custom data.
+            final CompoundTag customData = item.dataContainer().get(StructuredDataKey.CUSTOM_DATA);
+            if (customData == null) {
+                // Not valid
+                item.dataContainer().data().clear();
+            } else {
+                customData.keySet().removeIf(key -> !key.equals(ORIGINAL_HASHES_KEY));
+                item.dataContainer().data().keySet().removeIf(key -> key != StructuredDataKey.CUSTOM_DATA);
+            }
+        }
+
+        return super.handleItemToServer(connection, item);
+    }
+
+    @Override
+    protected void restoreBackupData(final Item item, final StructuredDataContainer container, final CompoundTag customData) {
+        // Keep original hashes intact until 1.21.5
+        final Tag hashes = customData.get(ORIGINAL_HASHES_KEY);
+
+        super.restoreBackupData(item, container, customData);
+
+        if (hashes != null) {
+            customData.put(ORIGINAL_HASHES_KEY, hashes);
+
+            // Add back
+            if (!container.has(StructuredDataKey.CUSTOM_DATA)) {
+                container.set(StructuredDataKey.CUSTOM_DATA, customData);
+                customData.putBoolean(MARKER_KEY, true);
+            }
+        }
+    }
+}

common/src/main/java/com/viaversion/viabackwards/api/rewriters/BackwardsItemRewriter.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -24,15 +24,20 @@ import com.viaversion.nbt.tag.ListTag;
 import com.viaversion.nbt.tag.NumberTag;
 import com.viaversion.nbt.tag.StringTag;
 import com.viaversion.nbt.tag.Tag;
+import com.viaversion.viabackwards.ViaBackwards;
 import com.viaversion.viabackwards.api.BackwardsProtocol;
 import com.viaversion.viabackwards.api.data.MappedItem;
+import com.viaversion.viabackwards.item.DataItemWithExtras;
 import com.viaversion.viaversion.api.connection.UserConnection;
 import com.viaversion.viaversion.api.minecraft.item.Item;
 import com.viaversion.viaversion.api.protocol.packet.ClientboundPacketType;
 import com.viaversion.viaversion.api.protocol.packet.ServerboundPacketType;
 import com.viaversion.viaversion.api.type.Type;
+import com.viaversion.viaversion.libs.gson.JsonElement;
+import java.util.List;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
+// <1.20.5
 public class BackwardsItemRewriter<C extends ClientboundPacketType, S extends ServerboundPacketType,
     T extends BackwardsProtocol<C, ?, ?, S>> extends BackwardsItemRewriterBase<C, S, T> {
 
@@ -52,29 +57,45 @@ public class BackwardsItemRewriter<C extends ClientboundPacketType, S extends Se
 
         CompoundTag display = item.tag() != null ? item.tag().getCompoundTag("display") : null;
         if (protocol.getComponentRewriter() != null && display != null) {
-            // Handle name and lore components
-            StringTag name = display.getStringTag("Name");
-            if (name != null) {
-                String newValue = protocol.getComponentRewriter().processText(connection, name.getValue()).toString();
-                if (!newValue.equals(name.getValue())) {
-                    saveStringTag(display, name, "Name");
-                }
-
-                name.setValue(newValue);
+            final DataItemWithExtras fullItem;
+            if (item instanceof DataItemWithExtras) {
+                fullItem = (DataItemWithExtras) item;
+            } else {
+                item = fullItem = new DataItemWithExtras(item);
             }
 
-            ListTag<StringTag> lore = display.getListTag("Lore", StringTag.class);
+            // Handle name and lore components
+            final JsonElement name = fullItem.name();
+            if (name != null) {
+                final JsonElement updatedName = name.deepCopy();
+                protocol.getComponentRewriter().processText(connection, updatedName);
+                if (!updatedName.equals(name)) {
+                    final StringTag rawName = fullItem.rawName();
+                    saveStringTag(display, rawName, "Name");
+                    rawName.setValue(updatedName.toString());
+                }
+            }
+
+            final List<JsonElement> lore = fullItem.lore();
             if (lore != null) {
                 boolean changed = false;
-                for (StringTag loreEntry : lore) {
-                    String newValue = protocol.getComponentRewriter().processText(connection, loreEntry.getValue()).toString();
-                    if (!changed && !newValue.equals(loreEntry.getValue())) {
-                        // Backup original lore before doing any modifications
-                        changed = true;
-                        saveListTag(display, lore, "Lore");
+                final ListTag<StringTag> rawLore = fullItem.rawLore();
+                for (int i = 0; i < lore.size(); i++) {
+                    final JsonElement loreEntry = lore.get(i);
+                    final JsonElement updatedLoreEntry = loreEntry.deepCopy();
+                    protocol.getComponentRewriter().processText(connection, updatedLoreEntry);
+                    if (updatedLoreEntry.equals(loreEntry)) {
+                        continue;
                     }
 
-                    loreEntry.setValue(newValue);
+                    if (!changed) {
+                        // Backup original lore before doing any modifications
+                        changed = true;
+                        saveListTag(display, rawLore, "Lore");
+                    }
+
+                    final StringTag rawLoreEntry = rawLore.get(i);
+                    rawLoreEntry.setValue(updatedLoreEntry.toString());
                 }
             }
         }
@@ -94,7 +115,7 @@ public class BackwardsItemRewriter<C extends ClientboundPacketType, S extends Se
         item.setIdentifier(data.id());
 
         // Add custom model data
-        if (data.customModelData() != null && !item.tag().contains("CustomModelData")) {
+        if (ViaBackwards.getConfig().passOriginalItemNameToResourcePacks() && !item.tag().contains("CustomModelData")) {
             item.tag().putInt("CustomModelData", data.customModelData());
         }
 
@@ -113,7 +134,7 @@ public class BackwardsItemRewriter<C extends ClientboundPacketType, S extends Se
     public @Nullable Item handleItemToServer(UserConnection connection, @Nullable Item item) {
         if (item == null) return null;
 
-        super.handleItemToServer(connection, item);
+        item = super.handleItemToServer(connection, item);
         if (item.tag() != null) {
             Tag originalId = item.tag().remove(nbtTagName("id"));
             if (originalId instanceof IntTag) {

common/src/main/java/com/viaversion/viabackwards/api/rewriters/BackwardsItemRewriterBase.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -17,19 +17,17 @@
  */
 package com.viaversion.viabackwards.api.rewriters;
 
+import com.viaversion.nbt.tag.CompoundTag;
+import com.viaversion.nbt.tag.ListTag;
+import com.viaversion.nbt.tag.StringTag;
+import com.viaversion.nbt.tag.Tag;
 import com.viaversion.viabackwards.api.BackwardsProtocol;
 import com.viaversion.viaversion.api.connection.UserConnection;
 import com.viaversion.viaversion.api.minecraft.item.Item;
 import com.viaversion.viaversion.api.protocol.packet.ClientboundPacketType;
 import com.viaversion.viaversion.api.protocol.packet.ServerboundPacketType;
 import com.viaversion.viaversion.api.type.Type;
-import com.viaversion.nbt.tag.CompoundTag;
-import com.viaversion.nbt.tag.ListTag;
-import com.viaversion.nbt.tag.StringTag;
-import com.viaversion.nbt.tag.Tag;
 import com.viaversion.viaversion.rewriter.ItemRewriter;
-import java.util.ArrayList;
-import java.util.List;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
 public abstract class BackwardsItemRewriterBase<C extends ClientboundPacketType, S extends ServerboundPacketType,
@@ -49,7 +47,7 @@ public abstract class BackwardsItemRewriterBase<C extends ClientboundPacketType,
     @Override
     public @Nullable Item handleItemToServer(UserConnection connection, @Nullable Item item) {
         if (item == null) return null;
-        super.handleItemToServer(connection, item);
+        item = super.handleItemToServer(connection, item);
 
         restoreDisplayTag(item);
         return item;

common/src/main/java/com/viaversion/viabackwards/api/rewriters/BackwardsRegistryRewriter.java

@@ -0,0 +1,139 @@
+/*
+ * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
+ * 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.viabackwards.api.rewriters;
+
+import com.viaversion.nbt.tag.CompoundTag;
+import com.viaversion.nbt.tag.Tag;
+import com.viaversion.viabackwards.api.BackwardsProtocol;
+import com.viaversion.viaversion.api.connection.UserConnection;
+import com.viaversion.viaversion.api.data.FullMappings;
+import com.viaversion.viaversion.api.minecraft.RegistryEntry;
+import com.viaversion.viaversion.rewriter.RegistryDataRewriter;
+import com.viaversion.viaversion.util.Key;
+import com.viaversion.viaversion.util.TagUtil;
+import java.util.Map;
+
+public class BackwardsRegistryRewriter extends RegistryDataRewriter {
+
+    private final BackwardsProtocol<?, ?, ?, ?> protocol;
+
+    public BackwardsRegistryRewriter(final BackwardsProtocol<?, ?, ?, ?> protocol) {
+        super(protocol);
+        this.protocol = protocol;
+    }
+
+    @Override
+    public RegistryEntry[] handle(final UserConnection connection, final String key, final RegistryEntry[] entries) {
+        if (Key.stripMinecraftNamespace(key).equals("worldgen/biome")) {
+            for (final RegistryEntry entry : entries) {
+                final CompoundTag biome = (CompoundTag) entry.tag();
+                if (biome == null) {
+                    continue;
+                }
+
+                final CompoundTag effects = biome.getCompoundTag("effects");
+                updateBiomeEffects(effects);
+
+                final CompoundTag attributes = biome.getCompoundTag("attributes");
+                if (attributes != null) {
+                    updateAttributes(attributes);
+                }
+            }
+        }
+        return super.handle(connection, key, entries);
+    }
+
+    @Override
+    public void updateJukeboxSongs(final UserConnection connection, final RegistryEntry[] entries) {
+        super.updateJukeboxSongs(connection, entries);
+        for (final RegistryEntry entry : entries) {
+            if (entry.tag() == null) {
+                continue;
+            }
+
+            updateSound((CompoundTag) entry.tag(), "sound_event");
+        }
+    }
+
+    @Override
+    protected boolean updateBlockState(final Tag blockStateTag) {
+        if (!(blockStateTag instanceof CompoundTag blockState) || blockState.getStringTag("Name") == null) {
+            return super.updateBlockState(blockStateTag);
+        }
+
+        // Up to 26.2, block states use "Name" and "Properties" instead of "id" and "properties"
+        final FullMappings blockMappings = protocol.getMappingData().getFullBlockMappings();
+        if (blockMappings == null) {
+            return false;
+        }
+
+        final int blockId = blockMappings.id(blockState.getString("Name"));
+        if (blockId == -1 || protocol.getMappingData().hasBlockChanged(blockId)) {
+            // Replace unknown or changed blocks with a dummy state, else the client will fail to load the registry
+            blockState.putString("Name", "minecraft:dirt");
+            blockState.remove("Properties");
+            return true;
+        }
+        return false;
+    }
+
+    private void updateBiomeEffects(final CompoundTag effects) {
+        updateSound(effects.getCompoundTag("mood_sound"), "sound");
+        updateSound(effects.getCompoundTag("additions_sound"), "sound");
+        updateSound(effects.getCompoundTag("music"), "sound");
+        updateSound(effects, "ambient_sound");
+    }
+
+    private void updateAttributes(final CompoundTag attributes) {
+        final CompoundTag backgroundMusic = TagUtil.getNamespacedCompoundTag(attributes, "audio/background_music");
+        if (backgroundMusic != null) {
+            updateSound(backgroundMusic.getCompoundTag("default"), "sound");
+        }
+
+        final CompoundTag ambientSounds = TagUtil.getNamespacedCompoundTag(attributes, "audio/ambient_sounds");
+        if (ambientSounds != null) {
+            updateSound(ambientSounds, "loop");
+            updateSound(ambientSounds, "mood");
+            updateSound(ambientSounds, "additions");
+        }
+    }
+
+    private void updateSound(final CompoundTag tag, final String name) {
+        if (tag == null) {
+            return;
+        }
+
+        final String sound = tag.getString(name);
+        if (sound == null) {
+            return;
+        }
+
+        final String mappedSound = protocol.getMappingData().getMappedNamedSound(sound);
+        if (mappedSound != null) {
+            tag.putString(name, mappedSound);
+        } else if (name.equals("sound_id")) {
+            // If it's already an inlined sound
+            tag.putString(name, "minecraft:intentionally_empty");
+        } else {
+            // Write as custom sound, so the id doesn't actually need to exist later on
+            final CompoundTag soundEvent = new CompoundTag();
+            soundEvent.putString("sound_id", "minecraft:intentionally_empty");
+            tag.put(name, soundEvent);
+        }
+    }
+}

common/src/main/java/com/viaversion/viabackwards/api/rewriters/BackwardsStructuredItemRewriter.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -24,6 +24,7 @@ import com.viaversion.nbt.tag.IntTag;
 import com.viaversion.nbt.tag.ListTag;
 import com.viaversion.nbt.tag.StringTag;
 import com.viaversion.nbt.tag.Tag;
+import com.viaversion.viabackwards.ViaBackwards;
 import com.viaversion.viabackwards.api.BackwardsProtocol;
 import com.viaversion.viabackwards.api.data.BackwardsMappingData;
 import com.viaversion.viabackwards.api.data.MappedItem;
@@ -31,6 +32,7 @@ import com.viaversion.viaversion.api.connection.UserConnection;
 import com.viaversion.viaversion.api.minecraft.EitherHolder;
 import com.viaversion.viaversion.api.minecraft.Holder;
 import com.viaversion.viaversion.api.minecraft.HolderSet;
+import com.viaversion.viaversion.api.minecraft.SoundEvent;
 import com.viaversion.viaversion.api.minecraft.data.StructuredDataContainer;
 import com.viaversion.viaversion.api.minecraft.data.StructuredDataKey;
 import com.viaversion.viaversion.api.minecraft.item.Item;
@@ -38,72 +40,46 @@ import com.viaversion.viaversion.api.minecraft.item.data.CustomModelData1_21_4;
 import com.viaversion.viaversion.api.protocol.packet.ClientboundPacketType;
 import com.viaversion.viaversion.api.protocol.packet.ServerboundPacketType;
 import com.viaversion.viaversion.api.protocol.version.ProtocolVersion;
-import com.viaversion.viaversion.api.type.Type;
 import com.viaversion.viaversion.rewriter.StructuredItemRewriter;
+import com.viaversion.viaversion.util.ArrayUtil;
+import com.viaversion.viaversion.util.Key;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.function.BiConsumer;
 import java.util.function.Function;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
+// 1.21.5+
 public class BackwardsStructuredItemRewriter<C extends ClientboundPacketType, S extends ServerboundPacketType,
     T extends BackwardsProtocol<C, ?, ?, S>> extends StructuredItemRewriter<C, S, T> {
 
     private static final int[] EMPTY_INT_ARRAY = new int[0];
+    private static final String GLOBAL_MODEL_DATA_MARKER = "VB|injected_cmd";
 
-    public BackwardsStructuredItemRewriter(
-        T protocol,
-        Type<Item> itemType, Type<Item[]> itemArrayType, Type<Item> mappedItemType, Type<Item[]> mappedItemArrayType,
-        Type<Item> itemCostType, Type<Item> optionalItemCostType, Type<Item> mappedItemCostType, Type<Item> mappedOptionalItemCostType
-    ) {
-        super(protocol, itemType, itemArrayType, mappedItemType, mappedItemArrayType, itemCostType, optionalItemCostType, mappedItemCostType, mappedOptionalItemCostType);
-    }
+    private final String nbtTagName;
 
-    public BackwardsStructuredItemRewriter(final T protocol, final Type<Item> itemType, final Type<Item[]> itemArrayType, final Type<Item> mappedItemType, final Type<Item[]> mappedItemArrayType) {
-        super(protocol, itemType, itemArrayType, mappedItemType, mappedItemArrayType);
-    }
-
-    public BackwardsStructuredItemRewriter(final T protocol, final Type<Item> itemType, final Type<Item[]> itemArrayType) {
-        super(protocol, itemType, itemArrayType);
+    public BackwardsStructuredItemRewriter(T protocol) {
+        super(protocol);
+        this.nbtTagName = "VB|" + protocol.getClass().getSimpleName();
     }
 
     @Override
-    public Item handleItemToClient(final UserConnection connection, final Item item) {
-        if (item.isEmpty()) {
-            return item;
-        }
-
-        final StructuredDataContainer dataContainer = item.dataContainer();
-        updateItemDataComponentTypeIds(dataContainer, true);
+    protected void backupInconvertibleData(final UserConnection connection, final Item item, final StructuredDataContainer dataContainer, final CompoundTag backupTag) {
+        super.backupInconvertibleData(connection, item, dataContainer, backupTag);
 
         final BackwardsMappingData mappingData = protocol.getMappingData();
         final MappedItem mappedItem = mappingData != null ? mappingData.getMappedItem(item.identifier()) : null;
         if (mappedItem == null) {
-            // Just rewrite the id
-            if (mappingData != null && mappingData.getItemMappings() != null) {
-                item.setIdentifier(mappingData.getNewItemId(item.identifier()));
-            }
-
-            updateItemDataComponents(connection, item, true);
-            return item;
+            return;
         }
 
-        // Save original id, set remapped id
-        final CompoundTag tag = createCustomTag(item);
-        tag.putInt(nbtTagName("id"), item.identifier());
-        item.setIdentifier(mappedItem.id());
+        final CompoundTag customTag = createCustomTag(item);
+        customTag.putInt(nbtTagName("id"), item.identifier()); // Save original id
 
         // Add custom model data
-        if (mappedItem.customModelData() != null) {
+        if (ViaBackwards.getConfig().passOriginalItemNameToResourcePacks()) {
             if (connection.getProtocolInfo().protocolVersion().newerThanOrEqualTo(ProtocolVersion.v1_21_4)) {
-                if (!dataContainer.has(StructuredDataKey.CUSTOM_MODEL_DATA1_21_4)) {
-                    dataContainer.set(StructuredDataKey.CUSTOM_MODEL_DATA1_21_4, new CustomModelData1_21_4(
-                        new float[]{mappedItem.customModelData().floatValue()},
-                        new boolean[0],
-                        new String[0],
-                        EMPTY_INT_ARRAY
-                    ));
-                }
+                addCustomModelData(item, mappedItem, customTag);
             } else if (!dataContainer.has(StructuredDataKey.CUSTOM_MODEL_DATA1_20_5)) {
                 dataContainer.set(StructuredDataKey.CUSTOM_MODEL_DATA1_20_5, mappedItem.customModelData());
             }
@@ -112,38 +88,61 @@ public class BackwardsStructuredItemRewriter<C extends ClientboundPacketType, S
         // Set custom name - only done if there is no original one
         if (!dataContainer.has(StructuredDataKey.CUSTOM_NAME)) {
             dataContainer.set(StructuredDataKey.CUSTOM_NAME, mappedItem.tagName());
-            tag.putBoolean(nbtTagName("added_custom_name"), true);
+            customTag.putBoolean(nbtTagName("added_custom_name"), true);
         }
+    }
 
-        updateItemDataComponents(connection, item, true);
-        return item;
+    private void addCustomModelData(final Item item, final MappedItem mappedItem, final CompoundTag customTag) {
+        final StructuredDataContainer dataContainer = item.dataContainer();
+        CustomModelData1_21_4 customModelData = dataContainer.get(StructuredDataKey.CUSTOM_MODEL_DATA1_21_4);
+        if (customModelData == null) {
+            // Add both the identifier string and custom model data
+            customModelData = new CustomModelData1_21_4(
+                new float[]{mappedItem.customModelData()},
+                new boolean[0],
+                new String[]{protocol.getMappingData().getFullItemMappings().identifier(item.identifier())},
+                EMPTY_INT_ARRAY
+            );
+            dataContainer.set(StructuredDataKey.CUSTOM_MODEL_DATA1_21_4, customModelData);
+            // Add one global marker and one for this specific version, so it is removed at the correct protocol
+            customTag.putBoolean(GLOBAL_MODEL_DATA_MARKER, true);
+            customTag.putBoolean(nbtTagName("added_custom_model_data"), true);
+        } else if (!customTag.contains(GLOBAL_MODEL_DATA_MARKER)) {
+            final String identifier = protocol.getMappingData().getFullItemMappings().identifier(item.identifier());
+            dataContainer.set(StructuredDataKey.CUSTOM_MODEL_DATA1_21_4, new CustomModelData1_21_4(
+                customModelData.floats(), customModelData.booleans(), ArrayUtil.add(customModelData.strings(), identifier), customModelData.colors()
+            ));
+            customTag.putBoolean(GLOBAL_MODEL_DATA_MARKER, true);
+            customTag.putString(nbtTagName("injected_custom_model_data"), identifier);
+        }
     }
 
     @Override
-    public Item handleItemToServer(final UserConnection connection, final Item item) {
-        if (item.isEmpty()) {
-            return item;
+    protected void restoreBackupData(final Item item, final StructuredDataContainer container, final CompoundTag customData) {
+        super.restoreBackupData(item, container, customData);
+        if (removeBackupTag(customData, "id") instanceof final IntTag originalTag) {
+            item.setIdentifier(originalTag.asInt());
+            removeCustomTag(container, customData);
         }
 
-        final StructuredDataContainer dataContainer = item.dataContainer();
-        updateItemDataComponentTypeIds(dataContainer, false);
-
-        final BackwardsMappingData mappingData = protocol.getMappingData();
-        if (mappingData != null && mappingData.getItemMappings() != null) {
-            item.setIdentifier(mappingData.getOldItemId(item.identifier()));
+        if (removeBackupTag(customData, "injected_custom_model_data") instanceof StringTag injectedCustomModelData) {
+            customData.remove(GLOBAL_MODEL_DATA_MARKER);
+            container.replace(StructuredDataKey.CUSTOM_MODEL_DATA1_21_4, customModelData -> {
+                final String target = injectedCustomModelData.getValue();
+                final String[] strings = customModelData.strings();
+                for (int i = 0; i < strings.length; i++) {
+                    if (strings[i].equals(target)) {
+                        // Remove the injected string
+                        final String[] filteredStrings = ArrayUtil.remove(strings, i);
+                        return new CustomModelData1_21_4(customModelData.floats(), customModelData.booleans(), filteredStrings, customModelData.colors());
+                    }
+                }
+                return customModelData;
+            });
+        } else if (removeBackupTag(customData, "added_custom_model_data") != null) {
+            customData.remove(GLOBAL_MODEL_DATA_MARKER);
+            container.remove(StructuredDataKey.CUSTOM_MODEL_DATA1_21_4);
         }
-
-        final CompoundTag customData = dataContainer.get(StructuredDataKey.CUSTOM_DATA);
-        if (customData != null) {
-            if (customData.remove(nbtTagName("id")) instanceof final IntTag originalTag) {
-                item.setIdentifier(originalTag.asInt());
-                removeCustomTag(dataContainer, customData);
-            }
-        }
-
-        restoreTextComponents(item);
-        updateItemDataComponents(connection, item, false);
-        return item;
     }
 
     protected void saveListTag(CompoundTag tag, ListTag<?> original, String name) {
@@ -291,6 +290,20 @@ public class BackwardsStructuredItemRewriter<C extends ClientboundPacketType, S
         }
     }
 
+    protected void saveKeyData(final StructuredDataKey<Key> key, final StructuredDataContainer data, final CompoundTag backupTag) {
+        final Key value = data.get(key);
+        if (value != null) {
+            backupTag.putString(key.identifier(), value.original());
+        }
+    }
+
+    protected void restoreKeyData(final StructuredDataKey<Key> key, final StructuredDataContainer data, final CompoundTag backupTag) {
+        final String value = backupTag.getString(key.identifier());
+        if (value != null) {
+            data.set(key, Key.of(value));
+        }
+    }
+
     protected void saveIntData(final StructuredDataKey<Integer> key, final StructuredDataContainer data, final CompoundTag backupTag) {
         final Integer variant = data.get(key);
         if (variant != null) {
@@ -319,8 +332,31 @@ public class BackwardsStructuredItemRewriter<C extends ClientboundPacketType, S
         }
     }
 
+    protected void saveSoundEventHolder(final CompoundTag tag, final Holder<SoundEvent> holder) {
+        tag.put("sound_event", holderToTag(holder, this::saveSoundEvent));
+    }
+
+    protected void saveSoundEvent(final SoundEvent soundEvent, final CompoundTag tag) {
+        tag.putString("identifier", soundEvent.identifier());
+        if (soundEvent.fixedRange() != null) {
+            tag.putFloat("fixed_range", soundEvent.fixedRange());
+        }
+    }
+
+    protected Holder<SoundEvent> restoreSoundEventHolder(final CompoundTag tag) {
+        return restoreSoundEventHolder(tag, "sound_event");
+    }
+
+    protected Holder<SoundEvent> restoreSoundEventHolder(final CompoundTag tag, final String key) {
+        return restoreHolder(tag, key, soundEventTag -> {
+            final String identifier = soundEventTag.getString("identifier");
+            final FloatTag fixedRange = soundEventTag.getFloatTag("fixed_range");
+            return new SoundEvent(identifier, fixedRange != null ? fixedRange.asFloat() : null);
+        });
+    }
+
     @Override
     public String nbtTagName() {
-        return "VB|" + protocol.getClass().getSimpleName();
+        return this.nbtTagName;
     }
 }

common/src/main/java/com/viaversion/viabackwards/api/rewriters/EnchantmentRewriter.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -17,12 +17,12 @@
  */
 package com.viaversion.viabackwards.api.rewriters;
 
-import com.viaversion.viabackwards.utils.ChatUtil;
-import com.viaversion.viaversion.api.minecraft.item.Item;
 import com.viaversion.nbt.tag.CompoundTag;
 import com.viaversion.nbt.tag.ListTag;
 import com.viaversion.nbt.tag.NumberTag;
 import com.viaversion.nbt.tag.StringTag;
+import com.viaversion.viabackwards.utils.ChatUtil;
+import com.viaversion.viaversion.api.minecraft.item.Item;
 import com.viaversion.viaversion.util.Key;
 import java.util.ArrayList;
 import java.util.HashMap;

common/src/main/java/com/viaversion/viabackwards/api/rewriters/EntityRewriter.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -18,8 +18,7 @@
 package com.viaversion.viabackwards.api.rewriters;
 
 import com.viaversion.viabackwards.api.BackwardsProtocol;
-import com.viaversion.viaversion.api.data.entity.EntityTracker;
-import com.viaversion.viaversion.api.minecraft.entities.EntityType;
+import com.viaversion.viaversion.api.data.entity.TrackedEntity;
 import com.viaversion.viaversion.api.minecraft.entitydata.EntityDataType;
 import com.viaversion.viaversion.api.protocol.packet.ClientboundPacketType;
 import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
@@ -37,110 +36,28 @@ public abstract class EntityRewriter<C extends ClientboundPacketType, T extends
         super(protocol, displayType, 2, displayVisibilityType, 3);
     }
 
-    @Override
-    public void registerTrackerWithData(C packetType, EntityType fallingBlockType) {
-        protocol.registerClientbound(packetType, wrapper -> {
-            wrapper.passthrough(Types.VAR_INT); // Entity ID
-            wrapper.passthrough(Types.UUID); // Entity UUID
-            wrapper.passthrough(Types.VAR_INT); // Entity Type
-            wrapper.passthrough(Types.DOUBLE); // X
-            wrapper.passthrough(Types.DOUBLE); // Y
-            wrapper.passthrough(Types.DOUBLE); // Z
-            wrapper.passthrough(Types.BYTE); // Pitch
-            wrapper.passthrough(Types.BYTE); // Yaw
-            wrapper.passthrough(Types.INT); // Data
-            getSpawnTrackerWithDataHandler(fallingBlockType).handle(wrapper);
-        });
-    }
-
-    @Override
-    public void registerTrackerWithData1_19(C packetType, EntityType fallingBlockType) {
-        protocol.registerClientbound(packetType, wrapper -> {
-            wrapper.passthrough(Types.VAR_INT); // Entity id
-            wrapper.passthrough(Types.UUID); // Entity UUID
-            wrapper.passthrough(Types.VAR_INT); // Entity type
-            wrapper.passthrough(Types.DOUBLE); // X
-            wrapper.passthrough(Types.DOUBLE); // Y
-            wrapper.passthrough(Types.DOUBLE); // Z
-            wrapper.passthrough(Types.BYTE); // Pitch
-            wrapper.passthrough(Types.BYTE); // Yaw
-            wrapper.passthrough(Types.BYTE); // Head yaw
-            wrapper.passthrough(Types.VAR_INT); // Data
-            getSpawnTrackerWithDataHandler1_19(fallingBlockType).handle(wrapper);
-        });
-    }
-
-    public PacketHandler getSpawnTrackerWithDataHandler(EntityType fallingBlockType) {
+    public PacketHandler getSpawnTrackerWithDataHandler() {
         return wrapper -> {
-            // Check against the UNMAPPED entity type
-            EntityType entityType = trackAndMapEntity(wrapper);
-            if (entityType == fallingBlockType) {
+            int entityId = wrapper.get(Types.VAR_INT, 0);
+            int typeId = wrapper.get(Types.VAR_INT, 1);
+            TrackedEntity entity = trackAndRewrite(wrapper, typeId, entityId);
+            if (entity.entityType() == fallingBlockType()) {
                 int blockState = wrapper.get(Types.INT, 0);
                 wrapper.set(Types.INT, 0, protocol.getMappingData().getNewBlockStateId(blockState));
             }
         };
     }
 
-    public PacketHandler getSpawnTrackerWithDataHandler1_19(EntityType fallingBlockType) {
-        return wrapper -> {
-            if (protocol.getMappingData() == null) {
-                return;
-            }
+    public void trackSpawnWithData1_19(final PacketWrapper wrapper, final int data) {
+        if (protocol.getMappingData() == null) {
+            return;
+        }
 
-            // Check against the UNMAPPED entity type
-            EntityType entityType = trackAndMapEntity(wrapper);
-            if (entityType == fallingBlockType) {
-                int blockState = wrapper.get(Types.VAR_INT, 2);
-                wrapper.set(Types.VAR_INT, 2, protocol.getMappingData().getNewBlockStateId(blockState));
-            }
-        };
-    }
-
-    public void registerSpawnTracker(C packetType) {
-        protocol.registerClientbound(packetType, wrapper -> {
-            wrapper.passthrough(Types.VAR_INT); // Entity ID
-            wrapper.passthrough(Types.UUID); // Entity UUID
-            wrapper.passthrough(Types.VAR_INT); // Entity Type
-            trackAndMapEntity(wrapper);
-        });
-    }
-
-    /**
-     * Returns a handler to track the current world and uncache entity data on world changes.
-     *
-     * @return handler to track the current world
-     */
-    public PacketHandler worldTrackerHandlerByKey() {
-        return wrapper -> {
-            EntityTracker tracker = tracker(wrapper.user());
-            String world = wrapper.get(Types.STRING, 1);
-            if (tracker.currentWorld() != null && !tracker.currentWorld().equals(world)) {
-                tracker.clearEntities();
-            }
-            tracker.setCurrentWorld(world);
-        };
-    }
-
-    /**
-     * Sets the mapped entity id and returns the unmapped entity type.
-     *
-     * @param wrapper packet wrapper
-     * @return unmapped (!) entity type
-     */
-    protected EntityType trackAndMapEntity(PacketWrapper wrapper) {
+        int entityId = wrapper.get(Types.VAR_INT, 0);
         int typeId = wrapper.get(Types.VAR_INT, 1);
-        EntityType entityType = typeFromId(typeId);
-        if (entityType == null) {
-            return null;
+        TrackedEntity entity = trackAndRewrite(wrapper, typeId, entityId);
+        if (entity.entityType() == fallingBlockType()) {
+            wrapper.set(Types.VAR_INT, 2, protocol.getMappingData().getNewBlockStateId(data));
         }
-
-        tracker(wrapper.user()).addEntity(wrapper.get(Types.VAR_INT, 0), entityType);
-
-        int mappedTypeId = newEntityId(entityType.getId());
-        if (typeId != mappedTypeId) {
-            wrapper.set(Types.VAR_INT, 1, mappedTypeId);
-        }
-
-        return entityType;
     }
 }

common/src/main/java/com/viaversion/viabackwards/api/rewriters/EntityRewriterBase.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -23,8 +23,6 @@ import com.viaversion.viabackwards.api.BackwardsProtocol;
 import com.viaversion.viabackwards.api.entities.storage.EntityReplacement;
 import com.viaversion.viabackwards.api.entities.storage.WrappedEntityData;
 import com.viaversion.viaversion.api.connection.UserConnection;
-import com.viaversion.viaversion.api.data.entity.EntityTracker;
-import com.viaversion.viaversion.api.data.entity.StoredEntityData;
 import com.viaversion.viaversion.api.data.entity.TrackedEntity;
 import com.viaversion.viaversion.api.minecraft.ClientWorld;
 import com.viaversion.viaversion.api.minecraft.Particle;
@@ -39,7 +37,6 @@ import com.viaversion.viaversion.libs.fastutil.ints.Int2ObjectMap;
 import com.viaversion.viaversion.libs.fastutil.ints.Int2ObjectOpenHashMap;
 import com.viaversion.viaversion.libs.gson.JsonElement;
 import com.viaversion.viaversion.rewriter.EntityRewriter;
-import com.viaversion.viaversion.rewriter.entitydata.EntityDataHandlerEvent;
 import java.util.List;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
@@ -86,12 +83,12 @@ public abstract class EntityRewriterBase<C extends ClientboundPacketType, T exte
                     // Add it as new entity data
                     entityDataList.add(new EntityData(displayNameIndex, displayNameDataType, displayNameObject));
                     addDisplayVisibilityData(entityDataList);
-                } else if (displayName.getValue() == null || displayName.getValue().toString().isEmpty()) {
+                } else if (isEmptyDisplayName(displayName.getValue())) {
                     // Overwrite the existing null/empty display name
                     displayName.setValue(displayNameObject);
                     addDisplayVisibilityData(entityDataList);
                 }
-            } else if (displayName != null && (displayName.getValue() == null || displayName.getValue().toString().isEmpty())) {
+            } else if (displayName != null && (isEmptyDisplayName(displayName))) {
                 // Overwrite null/empty display name
                 displayName.setValue(displayNameObject);
                 addDisplayVisibilityData(entityDataList);
@@ -104,6 +101,17 @@ public abstract class EntityRewriterBase<C extends ClientboundPacketType, T exte
         }
     }
 
+    private boolean isEmptyDisplayName(@Nullable Object o) {
+        if (o == null) {
+            return true;
+        } else if (o instanceof String s) {
+            return s.isEmpty();
+        } else if (o instanceof JsonElement element) {
+            return element.isJsonNull() || (element.isJsonPrimitive() && element.getAsJsonPrimitive().getAsString().isEmpty());
+        }
+        return false;
+    }
+
     private void addDisplayVisibilityData(List<EntityData> entityDataList) {
         if (alwaysShowOriginalMobName()) {
             removeData(displayVisibilityIndex, entityDataList);
@@ -140,10 +148,6 @@ public abstract class EntityRewriterBase<C extends ClientboundPacketType, T exte
         return entityDataMappings.get(type.getId());
     }
 
-    protected @Nullable StoredEntityData storedEntityData(EntityDataHandlerEvent event) {
-        return tracker(event.user()).entityData(event.entityId());
-    }
-
     /**
      * Maps an entity type to another with extra data.
      * Note that both types should be of the same version.
@@ -175,7 +179,7 @@ public abstract class EntityRewriterBase<C extends ClientboundPacketType, T exte
         filter().handler((event, data) -> {
             EntityDataType type = data.dataType();
             if (type == itemType) {
-                protocol.getItemRewriter().handleItemToClient(event.user(), data.value());
+                data.setValue(protocol.getItemRewriter().handleItemToClient(event.user(), data.value()));
             } else if (type == blockStateType) {
                 int value = data.value();
                 data.setValue(protocol.getMappingData().getNewBlockStateId(value));
@@ -227,6 +231,8 @@ public abstract class EntityRewriterBase<C extends ClientboundPacketType, T exte
         });
     }
 
+    // ------------------ Legacy methods
+
     // ONLY TRACKS, DOESN'T REWRITE IDS
     protected PacketHandler getTrackerHandler(Type<? extends Number> intType, int typeIndex) {
         return wrapper -> {
@@ -242,23 +248,9 @@ public abstract class EntityRewriterBase<C extends ClientboundPacketType, T exte
         return getTrackerHandler(Types.VAR_INT, 1);
     }
 
-    protected PacketHandler getTrackerHandler(EntityType entityType) {
-        return wrapper -> tracker(wrapper.user()).addEntity(wrapper.get(Types.VAR_INT, 0), entityType);
-    }
-
-    protected PacketHandler getPlayerTrackerHandler() {
-        return wrapper -> {
-            final int entityId = wrapper.get(Types.INT, 0);
-
-            final EntityTracker tracker = tracker(wrapper.user());
-            tracker(wrapper.user()).setClientEntityId(entityId);
-            tracker.addEntity(entityId, tracker.playerType());
-        };
-    }
-
     protected PacketHandler getDimensionHandler(int index) {
         return wrapper -> {
-            ClientWorld clientWorld = wrapper.user().getClientWorld(this.protocol.getClass());
+            ClientWorld clientWorld = wrapper.user().storables(this.protocol).clientWorld();
             int dimensionId = wrapper.get(Types.INT, index);
             if (clientWorld.setEnvironment(dimensionId)) {
                 tracker(wrapper.user()).clearEntities();

common/src/main/java/com/viaversion/viabackwards/api/rewriters/LegacyBlockItemRewriter.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -208,9 +208,9 @@ public abstract class LegacyBlockItemRewriter<C extends ClientboundPacketType, S
     }
 
     @Override
-    public @Nullable Item handleItemToServer(UserConnection connection, @Nullable final Item item) {
+    public @Nullable Item handleItemToServer(UserConnection connection, @Nullable Item item) {
         if (item == null) return null;
-        super.handleItemToServer(connection, item);
+        item = super.handleItemToServer(connection, item);
         if (item.tag() != null) {
             Tag originalId = item.tag().remove(nbtTagName("id"));
             if (originalId instanceof IntTag) {

common/src/main/java/com/viaversion/viabackwards/api/rewriters/LegacyEnchantmentRewriter.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -17,7 +17,6 @@
  */
 package com.viaversion.viabackwards.api.rewriters;
 
-import com.viaversion.viaversion.api.minecraft.item.Item;
 import com.viaversion.nbt.tag.ByteTag;
 import com.viaversion.nbt.tag.CompoundTag;
 import com.viaversion.nbt.tag.IntTag;
@@ -25,6 +24,7 @@ import com.viaversion.nbt.tag.ListTag;
 import com.viaversion.nbt.tag.NumberTag;
 import com.viaversion.nbt.tag.StringTag;
 import com.viaversion.nbt.tag.Tag;
+import com.viaversion.viaversion.api.minecraft.item.Item;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.HashSet;

common/src/main/java/com/viaversion/viabackwards/api/rewriters/LegacyEntityRewriter.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -21,6 +21,7 @@ import com.viaversion.viabackwards.api.BackwardsProtocol;
 import com.viaversion.viabackwards.api.entities.storage.EntityObjectData;
 import com.viaversion.viabackwards.api.entities.storage.EntityReplacement;
 import com.viaversion.viabackwards.api.entities.storage.WrappedEntityData;
+import com.viaversion.viaversion.api.data.entity.EntityTracker;
 import com.viaversion.viaversion.api.minecraft.ClientWorld;
 import com.viaversion.viaversion.api.minecraft.entities.EntityType;
 import com.viaversion.viaversion.api.minecraft.entities.ObjectType;
@@ -35,6 +36,7 @@ import com.viaversion.viaversion.api.type.Type;
 import com.viaversion.viaversion.api.type.Types;
 import java.util.HashMap;
 import java.util.List;
+import java.util.Locale;
 import java.util.Map;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
@@ -50,7 +52,7 @@ public abstract class LegacyEntityRewriter<C extends ClientboundPacketType, T ex
     }
 
     protected EntityObjectData mapObjectType(ObjectType oldObjectType, ObjectType replacement, int data) {
-        EntityObjectData entData = new EntityObjectData(protocol, oldObjectType.getType().name(), oldObjectType.getId(), replacement.getId(), data);
+        EntityObjectData entData = new EntityObjectData(protocol, oldObjectType.getType().name().toLowerCase(Locale.ROOT), oldObjectType.getId(), replacement.getId(), data);
         objectTypes.put(oldObjectType, entData);
         return entData;
     }
@@ -65,7 +67,7 @@ public abstract class LegacyEntityRewriter<C extends ClientboundPacketType, T ex
             public void register() {
                 map(Types.INT);
                 handler(wrapper -> {
-                    ClientWorld clientWorld = wrapper.user().getClientWorld(protocol.getClass());
+                    ClientWorld clientWorld = wrapper.user().storables(protocol).clientWorld();
                     if (clientWorld.setEnvironment(wrapper.get(Types.INT, 0))) {
                         tracker(wrapper.user()).clearEntities();
                     }
@@ -82,12 +84,13 @@ public abstract class LegacyEntityRewriter<C extends ClientboundPacketType, T ex
                 map(Types.UNSIGNED_BYTE); // 1 - Gamemode
                 map(Types.INT); // 2 - Dimension
                 handler(wrapper -> {
-                    ClientWorld clientWorld = wrapper.user().getClientWorld(protocol.getClass());
+                    ClientWorld clientWorld = wrapper.user().storables(protocol).clientWorld();
                     clientWorld.setEnvironment(wrapper.get(Types.INT, 1));
 
                     final int entityId = wrapper.get(Types.INT, 0);
-                    addTrackedEntity(wrapper, entityId, playerType);
-                    tracker(wrapper.user()).setClientEntityId(entityId);
+                    final EntityTracker tracker = tracker(wrapper.user());
+                    tracker.addEntity(entityId, playerType);
+                    tracker.setClientEntityId(entityId);
                 });
             }
         });
@@ -131,13 +134,13 @@ public abstract class LegacyEntityRewriter<C extends ClientboundPacketType, T ex
                 return;
             }
 
-            addTrackedEntity(wrapper, wrapper.get(Types.VAR_INT, 0), type);
+            tracker(wrapper.user()).addEntity(wrapper.get(Types.VAR_INT, 0), type);
         };
     }
 
     protected PacketHandler getTrackerAndDataHandler(Type<List<EntityData>> dataType, EntityType entityType) {
         return wrapper -> {
-            addTrackedEntity(wrapper, wrapper.get(Types.VAR_INT, 0), entityType);
+            tracker(wrapper.user()).addEntity(wrapper.get(Types.VAR_INT, 0), entityType);
             List<EntityData> entityDataList = wrapper.get(dataType, 0);
             handleEntityData(wrapper.get(Types.VAR_INT, 0), entityDataList, wrapper.user());
         };
@@ -162,11 +165,6 @@ public abstract class LegacyEntityRewriter<C extends ClientboundPacketType, T ex
         };
     }
 
-    @Deprecated
-    protected void addTrackedEntity(PacketWrapper wrapper, int entityId, EntityType type) {
-        tracker(wrapper.user()).addEntity(entityId, type);
-    }
-
     @FunctionalInterface
     protected interface IdSetter {
 

common/src/main/java/com/viaversion/viabackwards/api/rewriters/LegacySoundRewriter.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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

common/src/main/java/com/viaversion/viabackwards/api/rewriters/MapColorRewriter.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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

common/src/main/java/com/viaversion/viabackwards/api/rewriters/SoundRewriter.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -17,24 +17,22 @@
  */
 package com.viaversion.viabackwards.api.rewriters;
 
-import com.viaversion.viabackwards.api.BackwardsProtocol;
-import com.viaversion.viaversion.api.minecraft.Holder;
-import com.viaversion.viaversion.api.minecraft.SoundEvent;
+import com.viaversion.viaversion.api.data.Mappings;
+import com.viaversion.viaversion.api.protocol.AbstractProtocol;
 import com.viaversion.viaversion.api.protocol.packet.ClientboundPacketType;
-import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
 import com.viaversion.viaversion.api.protocol.remapper.PacketHandler;
 import com.viaversion.viaversion.api.type.Types;
 
 public class SoundRewriter<C extends ClientboundPacketType> extends com.viaversion.viaversion.rewriter.SoundRewriter<C> {
 
-    private final BackwardsProtocol<C, ?, ?, ?> protocol;
-
-    public SoundRewriter(final BackwardsProtocol<C, ?, ?, ?> protocol) {
+    public SoundRewriter(final AbstractProtocol<C, ?, ?, ?> protocol) {
         super(protocol);
-        this.protocol = protocol;
     }
 
     public void registerNamedSound(final C packetType) {
+        if (protocol.getMappingData() == null || Mappings.isFullIdentity(protocol.getMappingData().getFullSoundMappings())) {
+            return;
+        }
         protocol.registerClientbound(packetType, wrapper -> {
             wrapper.passthrough(Types.STRING); // Sound identifier
             getNamedSoundHandler().handle(wrapper);
@@ -42,36 +40,18 @@ public class SoundRewriter<C extends ClientboundPacketType> extends com.viaversi
     }
 
     public void registerStopSound(final C packetType) {
-        protocol.registerClientbound(packetType, wrapper -> getStopSoundHandler().handle(wrapper));
-    }
-
-    public PacketHandler getNamedSoundHandler() {
-        return wrapper -> {
-            final String soundId = wrapper.get(Types.STRING, 0);
-            final String mappedId = protocol.getMappingData().getMappedNamedSound(soundId);
-            if (mappedId == null) {
-                return;
-            }
-
-            if (!mappedId.isEmpty()) {
-                wrapper.set(Types.STRING, 0, mappedId);
-            } else {
-                wrapper.cancel();
-            }
-        };
-    }
-
-    public PacketHandler getStopSoundHandler() {
-        return wrapper -> {
+        if (protocol.getMappingData() == null || Mappings.isFullIdentity(protocol.getMappingData().getFullSoundMappings())) {
+            return;
+        }
+        protocol.registerClientbound(packetType, wrapper -> {
             final byte flags = wrapper.passthrough(Types.BYTE);
-            if ((flags & 0x02) == 0) return; // No sound specified
-
             if ((flags & 0x01) != 0) {
                 wrapper.passthrough(Types.VAR_INT); // Source
             }
 
+            if ((flags & 0x02) == 0) return; // No sound specified
             final String soundId = wrapper.read(Types.STRING);
-            final String mappedId = protocol.getMappingData().getMappedNamedSound(soundId);
+            final String mappedId = protocol.getMappingData().getFullSoundMappings().mappedIdentifier(soundId);
             if (mappedId == null) {
                 // No mapping found
                 wrapper.write(Types.STRING, soundId);
@@ -84,45 +64,22 @@ public class SoundRewriter<C extends ClientboundPacketType> extends com.viaversi
                 // Cancel if set to empty
                 wrapper.cancel();
             }
-        };
+        });
     }
 
-    @Override
-    public void registerSound1_19_3(final C packetType) {
-        protocol.registerClientbound(packetType, getSoundHandler1_19_3());
-    }
-
-    public PacketHandler getSoundHandler1_19_3() {
+    public PacketHandler getNamedSoundHandler() {
         return wrapper -> {
-            Holder<SoundEvent> soundEventHolder = wrapper.read(Types.SOUND_EVENT);
-            if (soundEventHolder.isDirect()) {
-                wrapper.write(Types.SOUND_EVENT, rewriteSoundEvent(wrapper, soundEventHolder));
+            final String soundId = wrapper.get(Types.STRING, 0);
+            final String mappedId = protocol.getMappingData().getFullSoundMappings().mappedIdentifier(soundId);
+            if (mappedId == null) {
                 return;
             }
 
-            final int mappedId = idRewriter.rewrite(soundEventHolder.id());
-            if (mappedId == -1) {
+            if (!mappedId.isEmpty()) {
+                wrapper.set(Types.STRING, 0, mappedId);
+            } else {
                 wrapper.cancel();
-                return;
             }
-
-            if (mappedId != soundEventHolder.id()) {
-                soundEventHolder = Holder.of(mappedId);
-            }
-
-            wrapper.write(Types.SOUND_EVENT, soundEventHolder);
         };
     }
-
-    public Holder<SoundEvent> rewriteSoundEvent(final PacketWrapper wrapper, final Holder<SoundEvent> soundEventHolder) {
-        final SoundEvent soundEvent = soundEventHolder.value();
-        final String mappedIdentifier = protocol.getMappingData().getMappedNamedSound(soundEvent.identifier());
-        if (mappedIdentifier != null) {
-            if (!mappedIdentifier.isEmpty()) {
-                return Holder.of(soundEvent.withIdentifier(mappedIdentifier));
-            }
-            wrapper.cancel();
-        }
-        return soundEventHolder;
-    }
 }

common/src/main/java/com/viaversion/viabackwards/api/rewriters/StructuredEnchantmentRewriter.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -33,6 +33,7 @@ import com.viaversion.viaversion.libs.fastutil.ints.Int2IntMap;
 import com.viaversion.viaversion.libs.fastutil.objects.ObjectIterator;
 import com.viaversion.viaversion.rewriter.IdRewriteFunction;
 import com.viaversion.viaversion.util.ComponentUtil;
+import com.viaversion.viaversion.util.Limit;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
@@ -195,7 +196,12 @@ public class StructuredEnchantmentRewriter {
         }
 
         final Enchantments enchantments = new Enchantments(tag.remove(itemRewriter.nbtTagName("show_" + key.identifier())) != null);
+        int i = 0;
         for (final CompoundTag enchantment : enchantmentsTag) {
+            if (i++ > 255) {
+                break;
+            }
+
             enchantments.add(enchantment.getInt("id"), enchantment.getInt("lvl"));
         }
         data.set(key, enchantments);

common/src/main/java/com/viaversion/viabackwards/api/rewriters/text/JsonNBTComponentRewriter.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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

common/src/main/java/com/viaversion/viabackwards/api/rewriters/text/NBTComponentRewriter.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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

common/src/main/java/com/viaversion/viabackwards/api/rewriters/text/TranslatableRewriter.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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

common/src/main/java/com/viaversion/viabackwards/item/DataItemWithExtras.java

@@ -0,0 +1,103 @@
+/*
+ * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
+ * 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.viabackwards.item;
+
+import com.viaversion.nbt.tag.CompoundTag;
+import com.viaversion.nbt.tag.ListTag;
+import com.viaversion.nbt.tag.StringTag;
+import com.viaversion.viaversion.api.minecraft.item.DataItem;
+import com.viaversion.viaversion.api.minecraft.item.Item;
+import com.viaversion.viaversion.libs.gson.JsonElement;
+import com.viaversion.viaversion.libs.gson.JsonParser;
+import com.viaversion.viaversion.libs.gson.JsonPrimitive;
+import com.viaversion.viaversion.libs.gson.JsonSyntaxException;
+import java.util.ArrayList;
+import java.util.List;
+import org.checkerframework.checker.nullness.qual.Nullable;
+
+/**
+ * Prevent expensive parsing/toString by checking against cached JsonElement instances, used from 1.14 to 1.20.5.
+ * <p>
+ * When using this, be careful not to break caching by modifying the display tag directly.
+ */
+public final class DataItemWithExtras extends DataItem {
+
+    private JsonElement name;
+    private List<JsonElement> lore;
+
+    public DataItemWithExtras(final Item from) {
+        setIdentifier(from.identifier());
+        setAmount(from.amount());
+        setData(from.data());
+        setTag(from.tag());
+
+        if (tag() == null) {
+            return;
+        }
+
+        final CompoundTag display = tag().getCompoundTag("display");
+        if (display == null) {
+            return;
+        }
+
+        final StringTag name = display.getStringTag("Name");
+        if (name != null) {
+            this.name = parse(name.getValue());
+        }
+
+        final ListTag<StringTag> lore = display.getListTag("Lore", StringTag.class);
+        if (lore != null) {
+            this.lore = new ArrayList<>(lore.size());
+            for (int i = 0; i < lore.size(); i++) {
+                this.lore.add(parse(lore.get(i).getValue()));
+            }
+        }
+    }
+
+    public @Nullable JsonElement name() {
+        return name;
+    }
+
+    public @Nullable StringTag rawName() {
+        if (tag() == null) {
+            return null;
+        }
+        final CompoundTag display = tag().getCompoundTag("display");
+        return display != null ? display.getStringTag("Name") : null;
+    }
+
+    public @Nullable List<JsonElement> lore() {
+        return lore;
+    }
+
+    public @Nullable ListTag<StringTag> rawLore() {
+        if (tag() == null) {
+            return null;
+        }
+        final CompoundTag display = tag().getCompoundTag("display");
+        return display != null ? display.getListTag("Lore", StringTag.class) : null;
+    }
+
+    private JsonElement parse(final String value) {
+        try {
+            return JsonParser.parseString(value);
+        } catch (final JsonSyntaxException e) {
+            return new JsonPrimitive(value);
+        }
+    }
+}

common/src/main/java/com/viaversion/viabackwards/protocol/registration/BackwardsRegistrations.java

@@ -0,0 +1,38 @@
+/*
+ * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
+ * 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.viabackwards.protocol.registration;
+
+import com.viaversion.viaversion.api.protocol.version.ProtocolVersion;
+import com.viaversion.viaversion.protocol.shared_registration.SharedRegistrations;
+
+public final class BackwardsRegistrations {
+
+    private static final SharedRegistrations REGISTRATIONS = SharedRegistrations.create();
+
+    public static void apply() {
+        REGISTRATIONS.registrations()
+            .range(ProtocolVersion.v1_10, ProtocolVersion.v1_19_3, RegistryRegistrations::registerNamedSound1_10)
+            .since(ProtocolVersion.v1_14, RegistryRegistrations::registerStopSound1_14)
+
+            .register();
+    }
+
+    public static SharedRegistrations registrations() {
+        return REGISTRATIONS;
+    }
+}

common/src/main/java/com/viaversion/viabackwards/protocol/registration/RegistryRegistrations.java

@@ -0,0 +1,36 @@
+/*
+ * 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.viabackwards.protocol.registration;
+
+import com.viaversion.viabackwards.api.rewriters.SoundRewriter;
+import com.viaversion.viaversion.api.protocol.packet.ClientboundPacketType;
+import com.viaversion.viaversion.protocol.shared_registration.PacketBound;
+import com.viaversion.viaversion.protocol.shared_registration.RegistrationContext;
+import com.viaversion.viaversion.protocols.v1_13_2to1_14.packet.ClientboundPackets1_14;
+import com.viaversion.viaversion.protocols.v1_9_1to1_9_3.packet.ClientboundPackets1_9_3;
+
+final class RegistryRegistrations {
+
+    static <CU extends ClientboundPacketType> void registerNamedSound1_10(final RegistrationContext<CU, ?> ctx) {
+        ctx.clientbound(ClientboundPackets1_9_3.CUSTOM_SOUND, new SoundRewriter<>(ctx.protocol())::registerNamedSound, PacketBound.REMOVED_AT_MAX);
+    }
+
+    static <CU extends ClientboundPacketType> void registerStopSound1_14(final RegistrationContext<CU, ?> ctx) {
+        ctx.clientbound(ClientboundPackets1_14.STOP_SOUND, new SoundRewriter<>(ctx.protocol())::registerStopSound);
+    }
+}

common/src/main/java/com/viaversion/viabackwards/protocol/template/BlockItemPacketRewriter1_99.java

@@ -1,73 +0,0 @@
-/*
- * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 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.viabackwards.protocol.template;
-
-import com.viaversion.viabackwards.api.rewriters.BackwardsStructuredItemRewriter;
-import com.viaversion.viaversion.api.type.types.chunk.ChunkType1_21_5;
-import com.viaversion.viaversion.api.type.types.version.Types1_21_4;
-import com.viaversion.viaversion.api.type.types.version.Types1_21_5;
-import com.viaversion.viaversion.protocols.v1_21_2to1_21_4.packet.ServerboundPacket1_21_4;
-import com.viaversion.viaversion.protocols.v1_21_2to1_21_4.packet.ServerboundPackets1_21_4;
-import com.viaversion.viaversion.protocols.v1_21_4to1_21_5.rewriter.RecipeDisplayRewriter1_21_5;
-import com.viaversion.viaversion.protocols.v1_21to1_21_2.packet.ClientboundPacket1_21_2;
-import com.viaversion.viaversion.protocols.v1_21to1_21_2.packet.ClientboundPackets1_21_2;
-import com.viaversion.viaversion.rewriter.BlockRewriter;
-import com.viaversion.viaversion.rewriter.RecipeDisplayRewriter;
-
-// To replace if needed:
-//   ChunkType1_21_5
-//   RecipeDisplayRewriter
-//   Types1_21_4
-final class BlockItemPacketRewriter1_99 extends BackwardsStructuredItemRewriter<ClientboundPacket1_21_2, ServerboundPacket1_21_4, Protocol1_98To1_99> {
-
-    public BlockItemPacketRewriter1_99(final Protocol1_98To1_99 protocol) {
-        super(protocol, Types1_21_4.ITEM, Types1_21_4.ITEM_ARRAY);
-        /*super(protocol,
-            Types1_21_4.ITEM, Types1_21_4.ITEM_ARRAY, Types1_OLD.ITEM, Types1_OLD.ITEM_ARRAY,
-            Types1_21_4.ITEM_COST, Types1_21_4.OPTIONAL_ITEM_COST, Types1_OLD.ITEM_COST, Types1_OLD.OPTIONAL_ITEM_COST
-        );*/
-    }
-
-    @Override
-    public void registerPackets() {
-        final BlockRewriter<ClientboundPacket1_21_2> blockRewriter = BlockRewriter.for1_20_2(protocol);
-        blockRewriter.registerBlockEvent(ClientboundPackets1_21_2.BLOCK_EVENT);
-        blockRewriter.registerBlockUpdate(ClientboundPackets1_21_2.BLOCK_UPDATE);
-        blockRewriter.registerSectionBlocksUpdate1_20(ClientboundPackets1_21_2.SECTION_BLOCKS_UPDATE);
-        blockRewriter.registerLevelEvent1_21(ClientboundPackets1_21_2.LEVEL_EVENT, 2001);
-        blockRewriter.registerLevelChunk1_19(ClientboundPackets1_21_2.LEVEL_CHUNK_WITH_LIGHT, ChunkType1_21_5::new);
-        blockRewriter.registerBlockEntityData(ClientboundPackets1_21_2.BLOCK_ENTITY_DATA);
-
-        // registerOpenScreen(ClientboundPackets1_21_2.OPEN_SCREEN);
-        protocol.registerClientbound(ClientboundPackets1_21_2.SET_CURSOR_ITEM, this::passthroughClientboundItem);
-        registerSetPlayerInventory(ClientboundPackets1_21_2.SET_PLAYER_INVENTORY);
-        registerCooldown1_21_2(ClientboundPackets1_21_2.COOLDOWN);
-        registerSetContent1_21_2(ClientboundPackets1_21_2.CONTAINER_SET_CONTENT);
-        registerSetSlot1_21_2(ClientboundPackets1_21_2.CONTAINER_SET_SLOT);
-        registerAdvancements1_20_3(ClientboundPackets1_21_2.UPDATE_ADVANCEMENTS);
-        registerSetEquipment(ClientboundPackets1_21_2.SET_EQUIPMENT);
-        registerMerchantOffers1_20_5(ClientboundPackets1_21_2.MERCHANT_OFFERS);
-        registerContainerClick1_21_5(ServerboundPackets1_21_4.CONTAINER_CLICK);
-        registerSetCreativeModeSlot1_21_5(ServerboundPackets1_21_4.SET_CREATIVE_MODE_SLOT, Types1_21_5.LENGTH_PREFIXED_ITEM, Types1_21_5.LENGTH_PREFIXED_ITEM); // Change this
-
-        final RecipeDisplayRewriter<ClientboundPacket1_21_2> recipeRewriter = new RecipeDisplayRewriter1_21_5<>(protocol);
-        recipeRewriter.registerUpdateRecipes(ClientboundPackets1_21_2.UPDATE_RECIPES);
-        recipeRewriter.registerRecipeBookAdd(ClientboundPackets1_21_2.RECIPE_BOOK_ADD);
-        recipeRewriter.registerPlaceGhostRecipe(ClientboundPackets1_21_2.PLACE_GHOST_RECIPE);
-    }
-}

common/src/main/java/com/viaversion/viabackwards/protocol/template/BlockItemPacketRewriter99_1.java

@@ -0,0 +1,64 @@
+/*
+ * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
+ * 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.viabackwards.protocol.template;
+
+import com.viaversion.nbt.tag.CompoundTag;
+import com.viaversion.viabackwards.api.rewriters.BackwardsStructuredItemRewriter;
+import com.viaversion.viaversion.api.connection.UserConnection;
+import com.viaversion.viaversion.api.minecraft.data.StructuredDataContainer;
+import com.viaversion.viaversion.api.minecraft.item.Item;
+import com.viaversion.viaversion.protocols.v1_21_11to26_1.packet.ClientboundPacket26_1;
+import com.viaversion.viaversion.protocols.v1_21_7to1_21_9.packet.ServerboundPacket1_21_9;
+
+// To replace if needed:
+//   ChunkType1_21_5
+//   RecipeDisplayRewriter
+final class BlockItemPacketRewriter99_1 extends BackwardsStructuredItemRewriter<ClientboundPacket26_1, ServerboundPacket1_21_9, Protocol99_1To98_1> {
+
+    public BlockItemPacketRewriter99_1(final Protocol99_1To98_1 protocol) {
+        super(protocol);
+    }
+
+    @Override
+    public void registerPackets() {
+    }
+
+    @Override
+    protected void handleItemDataComponentsToClient(final UserConnection connection, final Item item, final StructuredDataContainer container) {
+        super.handleItemDataComponentsToClient(connection, item, container);
+        // downgradeData(item, container); // static import VV method
+    }
+
+    @Override
+    protected void handleItemDataComponentsToServer(final UserConnection connection, final Item item, final StructuredDataContainer container) {
+        super.handleItemDataComponentsToServer(connection, item, container);
+        // upgradeData(item, container); // static import VV method
+    }
+
+    @Override
+    protected void restoreBackupData(final Item item, final StructuredDataContainer container, final CompoundTag customData) {
+        super.restoreBackupData(item, container, customData);
+        // restore any data if needed here
+    }
+
+    @Override
+    protected void backupInconvertibleData(final UserConnection connection, final Item item, final StructuredDataContainer dataContainer, final CompoundTag backupTag) {
+        super.backupInconvertibleData(connection, item, dataContainer, backupTag);
+        // back up any data if needed here, called before the method below
+    }
+}

common/src/main/java/com/viaversion/viabackwards/protocol/template/ComponentRewriter99_1.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -21,11 +21,11 @@ import com.viaversion.nbt.tag.CompoundTag;
 import com.viaversion.viabackwards.api.BackwardsProtocol;
 import com.viaversion.viabackwards.api.rewriters.text.NBTComponentRewriter;
 import com.viaversion.viaversion.api.connection.UserConnection;
-import com.viaversion.viaversion.protocols.v1_21to1_21_2.packet.ClientboundPacket1_21_2;
+import com.viaversion.viaversion.protocols.v1_21_11to26_1.packet.ClientboundPacket26_1;
 
-final class ComponentRewriter1_99 extends NBTComponentRewriter<ClientboundPacket1_21_2> {
+final class ComponentRewriter99_1 extends NBTComponentRewriter<ClientboundPacket26_1> {
 
-    public ComponentRewriter1_99(final BackwardsProtocol<ClientboundPacket1_21_2, ?, ?, ?> protocol) {
+    public ComponentRewriter99_1(final BackwardsProtocol<ClientboundPacket26_1, ?, ?, ?> protocol) {
         super(protocol);
     }
 

common/src/main/java/com/viaversion/viabackwards/protocol/template/EntityPacketRewriter1_99.java

@@ -1,91 +0,0 @@
-/*
- * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 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.viabackwards.protocol.template;
-
-import com.viaversion.viabackwards.api.rewriters.EntityRewriter;
-import com.viaversion.viaversion.api.minecraft.entities.EntityType;
-import com.viaversion.viaversion.api.minecraft.entities.EntityTypes1_21_4;
-import com.viaversion.viaversion.api.type.types.version.Types1_21_4;
-import com.viaversion.viaversion.protocols.v1_20_5to1_21.packet.ClientboundConfigurationPackets1_21;
-import com.viaversion.viaversion.protocols.v1_21to1_21_2.packet.ClientboundPacket1_21_2;
-import com.viaversion.viaversion.protocols.v1_21to1_21_2.packet.ClientboundPackets1_21_2;
-import com.viaversion.viaversion.rewriter.RegistryDataRewriter;
-
-// Replace if needed
-//  Types1_OLD
-//  Types1_21_4
-final class EntityPacketRewriter1_99 extends EntityRewriter<ClientboundPacket1_21_2, Protocol1_98To1_99> {
-
-    public EntityPacketRewriter1_99(final Protocol1_98To1_99 protocol) {
-        super(protocol, Types1_21_4.ENTITY_DATA_TYPES.optionalComponentType, Types1_21_4.ENTITY_DATA_TYPES.booleanType);
-    }
-
-    @Override
-    public void registerPackets() {
-        registerTrackerWithData1_19(ClientboundPackets1_21_2.ADD_ENTITY, EntityTypes1_21_4.FALLING_BLOCK);
-        registerSetEntityData(ClientboundPackets1_21_2.SET_ENTITY_DATA, /*Types1_OLD.ENTITY_DATA_LIST, */Types1_21_4.ENTITY_DATA_LIST); // Specify old and new entity data list if changed
-        registerRemoveEntities(ClientboundPackets1_21_2.REMOVE_ENTITIES);
-        registerPlayerAbilities(ClientboundPackets1_21_2.PLAYER_ABILITIES);
-        registerGameEvent(ClientboundPackets1_21_2.GAME_EVENT);
-        registerLogin1_20_5(ClientboundPackets1_21_2.LOGIN);
-        registerRespawn1_20_5(ClientboundPackets1_21_2.RESPAWN);
-
-        final RegistryDataRewriter registryDataRewriter = new RegistryDataRewriter(protocol);
-        protocol.registerClientbound(ClientboundConfigurationPackets1_21.REGISTRY_DATA, registryDataRewriter::handle);
-    }
-
-    @Override
-    protected void registerRewrites() {
-        /*filter().handler((event, data) -> {
-            int id = data.dataType().typeId();
-            if (id >= ac) {
-                return;
-            } else if (id >= ab) {
-                id--;
-            }
-
-            data.setDataType(Types1_21_4.ENTITY_DATA_TYPES.byId(id));
-        });*/
-
-        registerEntityDataTypeHandler1_20_3(
-            Types1_21_4.ENTITY_DATA_TYPES.itemType,
-            Types1_21_4.ENTITY_DATA_TYPES.blockStateType,
-            Types1_21_4.ENTITY_DATA_TYPES.optionalBlockStateType,
-            Types1_21_4.ENTITY_DATA_TYPES.particleType,
-            Types1_21_4.ENTITY_DATA_TYPES.particlesType,
-            Types1_21_4.ENTITY_DATA_TYPES.componentType,
-            Types1_21_4.ENTITY_DATA_TYPES.optionalComponentType
-        );
-
-        // Remove entity data of new entity type
-        // filter().type(EntityTypes1_21_4.SNIFFER).removeIndex(newIndex);
-    }
-
-    @Override
-    public void onMappingDataLoaded() {
-        // If types changed, uncomment to map them
-        // mapTypes();
-
-        // mapEntityTypeWithData(EntityTypes1_21_4.SNIFFER, EntityTypes1_21_4.RAVAGER).tagName();
-    }
-
-    @Override
-    public EntityType typeFromId(final int type) {
-        return EntityTypes1_21_4.getTypeFromId(type);
-    }
-}

common/src/main/java/com/viaversion/viabackwards/protocol/template/EntityPacketRewriter99_1.java

@@ -0,0 +1,75 @@
+/*
+ * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
+ * 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.viabackwards.protocol.template;
+
+import com.viaversion.viabackwards.api.rewriters.EntityRewriter;
+import com.viaversion.viaversion.api.minecraft.entities.EntityType;
+import com.viaversion.viaversion.api.minecraft.entities.EntityTypes1_21_11;
+import com.viaversion.viaversion.api.minecraft.entitydata.types.EntityDataTypes26_1;
+import com.viaversion.viaversion.api.type.types.version.VersionedTypes;
+import com.viaversion.viaversion.protocols.v1_21_11to26_1.packet.ClientboundPacket26_1;
+
+// Replace if needed
+//  VersionedTypes
+final class EntityPacketRewriter99_1 extends EntityRewriter<ClientboundPacket26_1, Protocol99_1To98_1> {
+
+    private static final EntityDataTypes26_1 MAPPED_DATA_TYPES = VersionedTypes.V26_1.entityDataTypes;
+
+    public EntityPacketRewriter99_1(final Protocol99_1To98_1 protocol) {
+        super(protocol, MAPPED_DATA_TYPES.optionalComponentType, MAPPED_DATA_TYPES.booleanType);
+    }
+
+    @Override
+    public void registerPackets() {
+    }
+
+    @Override
+    protected void registerRewrites() {
+        dataTypeMapper().register();
+        /* ... or like this for additions and removals that are not at the very end
+        dataTypeMapper()
+            .added(MAPPED_DATA_TYPES.catSoundVariant)
+            .removed(MAPPED_DATA_TYPES.cowSoundVariant)
+            .skip(MAPPED_DATA_TYPES.pigSoundVariant) // if neither removed nor added, but the value type has to be changed separately
+            .register();*/
+
+        registerEntityDataTypeHandler1_20_3(
+            MAPPED_DATA_TYPES.itemType,
+            MAPPED_DATA_TYPES.blockStateType,
+            MAPPED_DATA_TYPES.optionalBlockStateType,
+            MAPPED_DATA_TYPES.particleType,
+            MAPPED_DATA_TYPES.particlesType,
+            MAPPED_DATA_TYPES.componentType,
+            MAPPED_DATA_TYPES.optionalComponentType
+        );
+
+        // Remove entity data of new entity type
+        // filter().type(EntityTypes1_21_11.SNIFFER).removeIndex(newIndex);
+    }
+
+    @Override
+    public void onMappingDataLoaded() {
+        super.onMappingDataLoaded();
+        // mapEntityTypeWithData(EntityTypes1_21_11.SNIFFER, EntityTypes1_21_11.RAVAGER).tagName();
+    }
+
+    @Override
+    public EntityType typeFromId(final int type) {
+        return EntityTypes1_21_11.getTypeFromId(type);
+    }
+}

common/src/main/java/com/viaversion/viabackwards/protocol/template/Protocol1_98To1_99.java

@@ -1,146 +0,0 @@
-/*
- * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 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.viabackwards.protocol.template;
-
-import com.viaversion.viabackwards.api.BackwardsProtocol;
-import com.viaversion.viabackwards.api.data.BackwardsMappingData;
-import com.viaversion.viabackwards.api.rewriters.SoundRewriter;
-import com.viaversion.viabackwards.api.rewriters.text.NBTComponentRewriter;
-import com.viaversion.viaversion.api.connection.UserConnection;
-import com.viaversion.viaversion.api.minecraft.entities.EntityTypes1_21_4;
-import com.viaversion.viaversion.api.protocol.packet.provider.PacketTypesProvider;
-import com.viaversion.viaversion.api.protocol.packet.provider.SimplePacketTypesProvider;
-import com.viaversion.viaversion.api.type.types.version.Types1_21_4;
-import com.viaversion.viaversion.data.entity.EntityTrackerBase;
-import com.viaversion.viaversion.protocols.v1_20_3to1_20_5.packet.ServerboundConfigurationPackets1_20_5;
-import com.viaversion.viaversion.protocols.v1_20_5to1_21.Protocol1_20_5To1_21;
-import com.viaversion.viaversion.protocols.v1_20_5to1_21.packet.ClientboundConfigurationPackets1_21;
-import com.viaversion.viaversion.protocols.v1_21_2to1_21_4.packet.ServerboundPacket1_21_4;
-import com.viaversion.viaversion.protocols.v1_21_2to1_21_4.packet.ServerboundPackets1_21_4;
-import com.viaversion.viaversion.protocols.v1_21to1_21_2.packet.ClientboundPacket1_21_2;
-import com.viaversion.viaversion.protocols.v1_21to1_21_2.packet.ClientboundPackets1_21_2;
-import com.viaversion.viaversion.rewriter.ParticleRewriter;
-import com.viaversion.viaversion.rewriter.StatisticsRewriter;
-import com.viaversion.viaversion.rewriter.TagRewriter;
-
-import static com.viaversion.viaversion.util.ProtocolUtil.packetTypeMap;
-
-// Placeholders to replace (in the entire package):
-//   Protocol1_98To1_99, EntityPacketRewriter1_99, BlockItemPacketRewriter1_99
-//   Protocol1_20_5To1_21 (the ViaVersion protocol class the mappings depend on)
-//   ClientboundPacket1_21_2
-//   ServerboundPacket1_21_4
-//   ClientboundConfigurationPackets1_21
-//   ServerboundConfigurationPackets1_20_5
-//   EntityTypes1_21_4 (UNMAPPED type)
-//   Types1_21_4.PARTICLE
-//   1.99, 1.98
-final class Protocol1_98To1_99 extends BackwardsProtocol<ClientboundPacket1_21_2, ClientboundPacket1_21_2, ServerboundPacket1_21_4, ServerboundPacket1_21_4> {
-
-    // ViaBackwards uses its own mappings and also needs a translatablerewriter for translation mappings
-    public static final BackwardsMappingData MAPPINGS = new BackwardsMappingData("1.99", "1.98", Protocol1_20_5To1_21.class);
-    private final EntityPacketRewriter1_99 entityRewriter = new EntityPacketRewriter1_99(this);
-    private final BlockItemPacketRewriter1_99 itemRewriter = new BlockItemPacketRewriter1_99(this);
-    private final ParticleRewriter<ClientboundPacket1_21_2> particleRewriter = new ParticleRewriter<>(this, Types1_21_4.PARTICLE/*, Types1_OLD.PARTICLE*/);
-    private final NBTComponentRewriter<ClientboundPacket1_21_2> translatableRewriter = new ComponentRewriter1_99(this);
-    private final TagRewriter<ClientboundPacket1_21_2> tagRewriter = new TagRewriter<>(this);
-
-    public Protocol1_98To1_99() {
-        super(ClientboundPacket1_21_2.class, ClientboundPacket1_21_2.class, ServerboundPacket1_21_4.class, ServerboundPacket1_21_4.class);
-    }
-
-    @Override
-    protected void registerPackets() {
-        super.registerPackets();
-
-        tagRewriter.registerGeneric(ClientboundPackets1_21_2.UPDATE_TAGS);
-        tagRewriter.registerGeneric(ClientboundConfigurationPackets1_21.UPDATE_TAGS);
-
-        final SoundRewriter<ClientboundPacket1_21_2> soundRewriter = new SoundRewriter<>(this);
-        soundRewriter.registerSound1_19_3(ClientboundPackets1_21_2.SOUND);
-        soundRewriter.registerSound1_19_3(ClientboundPackets1_21_2.SOUND_ENTITY);
-        soundRewriter.registerStopSound(ClientboundPackets1_21_2.STOP_SOUND);
-
-        new StatisticsRewriter<>(this).register(ClientboundPackets1_21_2.AWARD_STATS);
-        //new AttributeRewriter<>(this).register1_21(ClientboundPackets1_21_2.UPDATE_ATTRIBUTES);
-
-        // Registers translatable mappings (missing a whole bunch still)
-        //translatableRewriter.registerOpenScreen1_14(ClientboundPackets1_21_2.OPEN_SCREEN); // Handled by registerOpenScreen in item rewriters
-        translatableRewriter.registerComponentPacket(ClientboundPackets1_21_2.SET_ACTION_BAR_TEXT);
-        translatableRewriter.registerComponentPacket(ClientboundPackets1_21_2.SET_TITLE_TEXT);
-        translatableRewriter.registerComponentPacket(ClientboundPackets1_21_2.SET_SUBTITLE_TEXT);
-        translatableRewriter.registerBossEvent(ClientboundPackets1_21_2.BOSS_EVENT);
-        translatableRewriter.registerComponentPacket(ClientboundPackets1_21_2.DISCONNECT);
-        translatableRewriter.registerTabList(ClientboundPackets1_21_2.TAB_LIST);
-        translatableRewriter.registerPlayerCombatKill1_20(ClientboundPackets1_21_2.PLAYER_COMBAT_KILL);
-        translatableRewriter.registerPlayerInfoUpdate1_21_4(ClientboundPackets1_21_2.PLAYER_INFO_UPDATE);
-        translatableRewriter.registerComponentPacket(ClientboundPackets1_21_2.SYSTEM_CHAT);
-        translatableRewriter.registerDisguisedChat(ClientboundPackets1_21_2.DISGUISED_CHAT);
-        translatableRewriter.registerPlayerChat1_21_5(ClientboundPackets1_21_2.PLAYER_CHAT);
-        translatableRewriter.registerPing();
-
-        // If needed for any particle, item, or block changes. Extend ParticleRewriter for particle serializer changes
-        particleRewriter.registerLevelParticles1_21_4(ClientboundPackets1_21_2.LEVEL_PARTICLES);
-        particleRewriter.registerExplode1_21_2(ClientboundPackets1_21_2.EXPLODE);
-    }
-
-    @Override
-    public void init(final UserConnection user) {
-        addEntityTracker(user, new EntityTrackerBase(user, EntityTypes1_21_4.PLAYER));
-    }
-
-    @Override
-    public BackwardsMappingData getMappingData() {
-        return MAPPINGS;
-    }
-
-    @Override
-    public EntityPacketRewriter1_99 getEntityRewriter() {
-        return entityRewriter;
-    }
-
-    @Override
-    public BlockItemPacketRewriter1_99 getItemRewriter() {
-        return itemRewriter;
-    }
-
-    @Override
-    public ParticleRewriter<ClientboundPacket1_21_2> getParticleRewriter() {
-        return particleRewriter;
-    }
-
-    @Override
-    public NBTComponentRewriter<ClientboundPacket1_21_2> getComponentRewriter() {
-        return translatableRewriter;
-    }
-
-    @Override
-    public TagRewriter<ClientboundPacket1_21_2> getTagRewriter() {
-        return tagRewriter;
-    }
-
-    @Override
-    protected PacketTypesProvider<ClientboundPacket1_21_2, ClientboundPacket1_21_2, ServerboundPacket1_21_4, ServerboundPacket1_21_4> createPacketTypesProvider() {
-        return new SimplePacketTypesProvider<>(
-            packetTypeMap(unmappedClientboundPacketType, ClientboundPackets1_21_2.class, ClientboundConfigurationPackets1_21.class),
-            packetTypeMap(mappedClientboundPacketType, ClientboundPackets1_21_2.class, ClientboundConfigurationPackets1_21.class),
-            packetTypeMap(mappedServerboundPacketType, ServerboundPackets1_21_4.class, ServerboundConfigurationPackets1_20_5.class),
-            packetTypeMap(unmappedServerboundPacketType, ServerboundPackets1_21_4.class, ServerboundConfigurationPackets1_20_5.class)
-        );
-    }
-}

common/src/main/java/com/viaversion/viabackwards/protocol/template/Protocol99_1To98_1.java

@@ -0,0 +1,156 @@
+/*
+ * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
+ * 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.viabackwards.protocol.template;
+
+import com.viaversion.viabackwards.api.BackwardsProtocol;
+import com.viaversion.viabackwards.api.data.BackwardsMappingData;
+import com.viaversion.viabackwards.api.rewriters.BackwardsRegistryRewriter;
+import com.viaversion.viabackwards.api.rewriters.text.NBTComponentRewriter;
+import com.viaversion.viaversion.api.connection.UserConnection;
+import com.viaversion.viaversion.api.protocol.packet.provider.PacketTypesProvider;
+import com.viaversion.viaversion.api.protocol.packet.provider.SimplePacketTypesProvider;
+import com.viaversion.viaversion.api.type.types.chunk.ChunkType26_1;
+import com.viaversion.viaversion.api.type.types.version.VersionedTypes;
+import com.viaversion.viaversion.api.type.types.version.VersionedTypesHolder;
+import com.viaversion.viaversion.protocols.v1_21_11to26_1.Protocol1_21_11To26_1;
+import com.viaversion.viaversion.protocols.v1_21_11to26_1.packet.ClientboundPacket26_1;
+import com.viaversion.viaversion.protocols.v1_21_11to26_1.packet.ClientboundPackets26_1;
+import com.viaversion.viaversion.protocols.v1_21_5to1_21_6.packet.ServerboundPackets1_21_6;
+import com.viaversion.viaversion.protocols.v1_21_7to1_21_9.packet.ClientboundConfigurationPackets1_21_9;
+import com.viaversion.viaversion.protocols.v1_21_7to1_21_9.packet.ServerboundConfigurationPackets1_21_9;
+import com.viaversion.viaversion.protocols.v1_21_7to1_21_9.packet.ServerboundPacket1_21_9;
+import com.viaversion.viaversion.protocols.v26_2to26_3.rewriter.RecipeDisplayRewriter26_3;
+import com.viaversion.viaversion.rewriter.BlockRewriter;
+import com.viaversion.viaversion.rewriter.ParticleRewriter;
+import com.viaversion.viaversion.rewriter.RecipeDisplayRewriter;
+import com.viaversion.viaversion.rewriter.TagRewriter;
+import com.viaversion.viaversion.rewriter.block.BlockRewriter1_21_5;
+
+import static com.viaversion.viaversion.util.ProtocolUtil.packetTypeMap;
+
+// Placeholders to replace (in the entire package):
+//   Protocol1_21_11To26_1 (the ViaVersion protocol class the mappings depend on)
+//   ClientboundPacket26_1
+//   ServerboundPacket1_21_9
+//   ClientboundConfigurationPackets1_21
+//   ServerboundConfigurationPackets1_20_5
+//   EntityTypes1_21_11 (UNMAPPED type)
+//   VersionedTypes.V26_1
+//   99.1, 98.1
+final class Protocol99_1To98_1 extends BackwardsProtocol<ClientboundPacket26_1, ClientboundPacket26_1, ServerboundPacket1_21_9, ServerboundPacket1_21_9> {
+
+    // ViaBackwards uses its own mappings and also needs a translatablerewriter for translation mappings
+    public static final BackwardsMappingData MAPPINGS = new BackwardsMappingData("99.1", "98.1", Protocol1_21_11To26_1.class); // Change the VV (!) protocol class
+    private final EntityPacketRewriter99_1 entityRewriter = new EntityPacketRewriter99_1(this);
+    private final BlockItemPacketRewriter99_1 itemRewriter = new BlockItemPacketRewriter99_1(this);
+    private final ParticleRewriter<ClientboundPacket26_1> particleRewriter = new ParticleRewriter<>(this);
+    private final NBTComponentRewriter<ClientboundPacket26_1> translatableRewriter = new ComponentRewriter99_1(this);
+    private final TagRewriter<ClientboundPacket26_1> tagRewriter = new TagRewriter<>(this);
+    private final BackwardsRegistryRewriter registryDataRewriter = new BackwardsRegistryRewriter(this);
+    private final BlockRewriter<ClientboundPacket26_1> blockRewriter = new BlockRewriter1_21_5<>(this, ChunkType26_1::new);
+    private final RecipeDisplayRewriter<ClientboundPacket26_1> recipeRewriter = new RecipeDisplayRewriter26_3<>(this);
+
+    public Protocol99_1To98_1() {
+        super(ClientboundPacket26_1.class, ClientboundPacket26_1.class, ServerboundPacket1_21_9.class, ServerboundPacket1_21_9.class);
+    }
+
+    @Override
+    protected void registerPackets() {
+        super.registerPackets();
+
+        // Remove newly synchronized registries to prevent errors on older clients
+        //registryDataRewriter.remove("worldgen/block_state_provider");
+    }
+
+    @Override
+    public void init(final UserConnection connection) {
+        addEntityTracker(connection);
+        addItemHasher(connection);
+    }
+
+    // If data beyond the tracker and hasher is required
+    //@Override
+    //public ProtocolStorablesBase createStorables() {
+    //    return new ProtocolStorables99_1();
+    //}
+
+    @Override
+    public BackwardsMappingData getMappingData() {
+        return MAPPINGS;
+    }
+
+    @Override
+    public EntityPacketRewriter99_1 getEntityRewriter() {
+        return entityRewriter;
+    }
+
+    @Override
+    public BlockItemPacketRewriter99_1 getItemRewriter() {
+        return itemRewriter;
+    }
+
+    @Override
+    public BlockRewriter<ClientboundPacket26_1> getBlockRewriter() {
+        return blockRewriter;
+    }
+
+    @Override
+    public RecipeDisplayRewriter<ClientboundPacket26_1> getRecipeRewriter() {
+        return recipeRewriter;
+    }
+
+    @Override
+    public BackwardsRegistryRewriter getRegistryDataRewriter() {
+        return registryDataRewriter;
+    }
+
+    @Override
+    public ParticleRewriter<ClientboundPacket26_1> getParticleRewriter() {
+        return particleRewriter;
+    }
+
+    @Override
+    public NBTComponentRewriter<ClientboundPacket26_1> getComponentRewriter() {
+        return translatableRewriter;
+    }
+
+    @Override
+    public TagRewriter<ClientboundPacket26_1> getTagRewriter() {
+        return tagRewriter;
+    }
+
+    @Override
+    public VersionedTypesHolder types() {
+        return VersionedTypes.V26_1;
+    }
+
+    @Override
+    public VersionedTypesHolder mappedTypes() {
+        return VersionedTypes.V26_1;
+    }
+
+    @Override
+    protected PacketTypesProvider<ClientboundPacket26_1, ClientboundPacket26_1, ServerboundPacket1_21_9, ServerboundPacket1_21_9> createPacketTypesProvider() {
+        return new SimplePacketTypesProvider<>(
+            packetTypeMap(unmappedClientboundPacketType, ClientboundPackets26_1.class, ClientboundConfigurationPackets1_21_9.class),
+            packetTypeMap(mappedClientboundPacketType, ClientboundPackets26_1.class, ClientboundConfigurationPackets1_21_9.class),
+            packetTypeMap(mappedServerboundPacketType, ServerboundPackets1_21_6.class, ServerboundConfigurationPackets1_21_9.class),
+            packetTypeMap(unmappedServerboundPacketType, ServerboundPackets1_21_6.class, ServerboundConfigurationPackets1_21_9.class)
+        );
+    }
+}

common/src/main/java/com/viaversion/viabackwards/protocol/v1_10to1_9_3/Protocol1_10To1_9_3.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -57,7 +57,7 @@ public class Protocol1_10To1_9_3 extends BackwardsProtocol<ClientboundPackets1_9
         itemRewriter.register();
 
         SoundRewriter<ClientboundPackets1_9_3> soundRewriter = new SoundRewriter<>(this);
-        registerClientbound(ClientboundPackets1_9_3.CUSTOM_SOUND, new PacketHandlers() {
+        replaceClientbound(ClientboundPackets1_9_3.CUSTOM_SOUND, new PacketHandlers() {
             @Override
             public void register() {
                 map(Types.STRING); // 0 - Sound name
@@ -70,7 +70,7 @@ public class Protocol1_10To1_9_3 extends BackwardsProtocol<ClientboundPackets1_9
                 handler(soundRewriter.getNamedSoundHandler());
             }
         });
-        registerClientbound(ClientboundPackets1_9_3.SOUND, new PacketHandlers() {
+        replaceClientbound(ClientboundPackets1_9_3.SOUND, new PacketHandlers() {
             @Override
             public void register() {
                 map(Types.VAR_INT); // 0 - Sound name
@@ -98,8 +98,8 @@ public class Protocol1_10To1_9_3 extends BackwardsProtocol<ClientboundPackets1_9
 
     @Override
     public void init(UserConnection user) {
-        user.addEntityTracker(this.getClass(), new EntityTrackerBase(user, EntityTypes1_10.EntityType.PLAYER));
-        user.addClientWorld(this.getClass(), new ClientWorld());
+        addEntityTracker(user, new EntityTrackerBase(user, EntityTypes1_10.EntityType.PLAYER));
+        user.storables(this).setClientWorld(new ClientWorld());
     }
 
     @Override
@@ -116,9 +116,4 @@ public class Protocol1_10To1_9_3 extends BackwardsProtocol<ClientboundPackets1_9
     public BlockItemPacketRewriter1_10 getItemRewriter() {
         return itemRewriter;
     }
-
-    @Override
-    public boolean hasMappingDataToLoad() {
-        return true;
-    }
 }

common/src/main/java/com/viaversion/viabackwards/protocol/v1_10to1_9_3/rewriter/BlockItemPacketRewriter1_10.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -50,7 +50,7 @@ public class BlockItemPacketRewriter1_10 extends LegacyBlockItemRewriter<Clientb
         registerSetCreativeModeSlot(ServerboundPackets1_9_3.SET_CREATIVE_MODE_SLOT);
 
         protocol.registerClientbound(ClientboundPackets1_9_3.LEVEL_CHUNK, wrapper -> {
-            ClientWorld clientWorld = wrapper.user().getClientWorld(Protocol1_10To1_9_3.class);
+            ClientWorld clientWorld = wrapper.user().storables(protocol).clientWorld();
 
             ChunkType1_9_3 type = ChunkType1_9_3.forEnvironment(clientWorld.getEnvironment());
             Chunk chunk = wrapper.passthrough(type);

common/src/main/java/com/viaversion/viabackwards/protocol/v1_10to1_9_3/rewriter/EntityPacketRewriter1_10.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -29,7 +29,6 @@ import com.viaversion.viaversion.api.minecraft.entitydata.EntityData;
 import com.viaversion.viaversion.api.minecraft.entitydata.types.EntityDataTypes1_9;
 import com.viaversion.viaversion.api.protocol.remapper.PacketHandlers;
 import com.viaversion.viaversion.api.type.Types;
-import com.viaversion.viaversion.api.type.types.version.Types1_9;
 import com.viaversion.viaversion.protocols.v1_9_1to1_9_3.packet.ClientboundPackets1_9_3;
 import java.util.List;
 
@@ -80,7 +79,7 @@ public class EntityPacketRewriter1_10 extends LegacyEntityRewriter<ClientboundPa
                 map(Types.SHORT); // 9 - Velocity X
                 map(Types.SHORT); // 10 - Velocity Y
                 map(Types.SHORT); // 11 - Velocity Z
-                map(Types1_9.ENTITY_DATA_LIST); // 12 - Entity data
+                map(Types.ENTITY_DATA_LIST1_9); // 12 - Entity data
 
                 // Track entity
                 handler(getTrackerHandler(Types.UNSIGNED_BYTE, 0));
@@ -93,7 +92,7 @@ public class EntityPacketRewriter1_10 extends LegacyEntityRewriter<ClientboundPa
                         return;
                     }
 
-                    List<EntityData> entityDataList = wrapper.get(Types1_9.ENTITY_DATA_LIST, 0);
+                    List<EntityData> entityDataList = wrapper.get(Types.ENTITY_DATA_LIST1_9, 0);
                     handleEntityData(wrapper.get(Types.VAR_INT, 0), entityDataList, wrapper.user());
 
                     EntityReplacement entityReplacement = entityDataForType(type);
@@ -122,14 +121,14 @@ public class EntityPacketRewriter1_10 extends LegacyEntityRewriter<ClientboundPa
                 map(Types.DOUBLE); // 4 - Z
                 map(Types.BYTE); // 5 - Yaw
                 map(Types.BYTE); // 6 - Pitch
-                map(Types1_9.ENTITY_DATA_LIST); // 7 - Entity data list
+                map(Types.ENTITY_DATA_LIST1_9); // 7 - Entity data list
 
-                handler(getTrackerAndDataHandler(Types1_9.ENTITY_DATA_LIST, EntityTypes1_11.EntityType.PLAYER));
+                handler(getTrackerAndDataHandler(Types.ENTITY_DATA_LIST1_9, EntityTypes1_11.EntityType.PLAYER));
             }
         });
 
         registerRemoveEntities(ClientboundPackets1_9_3.REMOVE_ENTITIES);
-        registerSetEntityData(ClientboundPackets1_9_3.SET_ENTITY_DATA, Types1_9.ENTITY_DATA_LIST);
+        registerSetEntityData(ClientboundPackets1_9_3.SET_ENTITY_DATA, Types.ENTITY_DATA_LIST1_9);
     }
 
     @Override
@@ -158,6 +157,9 @@ public class EntityPacketRewriter1_10 extends LegacyEntityRewriter<ClientboundPa
             }
         });
 
+        // Added index from incorrect entity data hierarchy, where potions add to item entities
+        filter().type(EntityTypes1_10.EntityType.POTION).addIndex(6);
+
         // Handle the missing NoGravity tag for every entity data
         filter().removeIndex(5);
     }

common/src/main/java/com/viaversion/viabackwards/protocol/v1_11_1to1_11/Protocol1_11_1To1_11.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -39,8 +39,8 @@ public class Protocol1_11_1To1_11 extends BackwardsProtocol<ClientboundPackets1_
 
     @Override
     public void init(UserConnection user) {
-        user.addEntityTracker(this.getClass(), new EntityTrackerBase(user, EntityTypes1_11.EntityType.PLAYER));
-        user.addClientWorld(this.getClass(), new ClientWorld());
+        addEntityTracker(user, new EntityTrackerBase(user, EntityTypes1_11.EntityType.PLAYER));
+        user.storables(this).setClientWorld(new ClientWorld());
     }
 
     @Override

common/src/main/java/com/viaversion/viabackwards/protocol/v1_11_1to1_11/rewriter/EntityPacketRewriter1_11_1.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -24,7 +24,6 @@ import com.viaversion.viaversion.api.minecraft.entities.EntityType;
 import com.viaversion.viaversion.api.minecraft.entities.EntityTypes1_11;
 import com.viaversion.viaversion.api.protocol.remapper.PacketHandlers;
 import com.viaversion.viaversion.api.type.Types;
-import com.viaversion.viaversion.api.type.types.version.Types1_9;
 import com.viaversion.viaversion.protocols.v1_9_1to1_9_3.packet.ClientboundPackets1_9_3;
 
 public class EntityPacketRewriter1_11_1 extends LegacyEntityRewriter<ClientboundPackets1_9_3, Protocol1_11_1To1_11> {
@@ -72,13 +71,13 @@ public class EntityPacketRewriter1_11_1 extends LegacyEntityRewriter<Clientbound
                 map(Types.SHORT); // 9 - Velocity X
                 map(Types.SHORT); // 10 - Velocity Y
                 map(Types.SHORT); // 11 - Velocity Z
-                map(Types1_9.ENTITY_DATA_LIST); // 12 - Entity data
+                map(Types.ENTITY_DATA_LIST1_9); // 12 - Entity data
 
                 // Track entity
                 handler(getTrackerHandler());
 
                 // Rewrite entity type / data
-                handler(getMobSpawnRewriter1_11(Types1_9.ENTITY_DATA_LIST));
+                handler(getMobSpawnRewriter1_11(Types.ENTITY_DATA_LIST1_9));
             }
         });
 
@@ -96,14 +95,14 @@ public class EntityPacketRewriter1_11_1 extends LegacyEntityRewriter<Clientbound
                 map(Types.DOUBLE); // 4 - Z
                 map(Types.BYTE); // 5 - Yaw
                 map(Types.BYTE); // 6 - Pitch
-                map(Types1_9.ENTITY_DATA_LIST); // 7 - Entity data list
+                map(Types.ENTITY_DATA_LIST1_9); // 7 - Entity data list
 
-                handler(getTrackerAndDataHandler(Types1_9.ENTITY_DATA_LIST, EntityTypes1_11.EntityType.PLAYER));
+                handler(getTrackerAndDataHandler(Types.ENTITY_DATA_LIST1_9, EntityTypes1_11.EntityType.PLAYER));
             }
         });
 
         registerRemoveEntities(ClientboundPackets1_9_3.REMOVE_ENTITIES);
-        registerSetEntityData(ClientboundPackets1_9_3.SET_ENTITY_DATA, Types1_9.ENTITY_DATA_LIST);
+        registerSetEntityData(ClientboundPackets1_9_3.SET_ENTITY_DATA, Types.ENTITY_DATA_LIST1_9);
     }
 
     @Override

common/src/main/java/com/viaversion/viabackwards/protocol/v1_11_1to1_11/rewriter/ItemPacketRewriter1_11_1.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -23,8 +23,6 @@ import com.viaversion.viabackwards.api.rewriters.LegacyEnchantmentRewriter;
 import com.viaversion.viabackwards.protocol.v1_11_1to1_11.Protocol1_11_1To1_11;
 import com.viaversion.viaversion.api.connection.UserConnection;
 import com.viaversion.viaversion.api.minecraft.item.Item;
-import com.viaversion.viaversion.api.protocol.remapper.PacketHandlers;
-import com.viaversion.viaversion.api.type.Type;
 import com.viaversion.viaversion.api.type.Types;
 import com.viaversion.viaversion.protocols.v1_9_1to1_9_3.packet.ClientboundPackets1_9_3;
 import com.viaversion.viaversion.protocols.v1_9_1to1_9_3.packet.ServerboundPackets1_9_3;
@@ -73,7 +71,7 @@ public class ItemPacketRewriter1_11_1 extends LegacyBlockItemRewriter<Clientboun
     @Override
     public Item handleItemToServer(UserConnection connection, Item item) {
         if (item == null) return null;
-        super.handleItemToServer(connection, item);
+        item = super.handleItemToServer(connection, item);
 
         enchantmentRewriter.handleToServer(item);
         return item;

common/src/main/java/com/viaversion/viabackwards/protocol/v1_11to1_10/Protocol1_11To1_10.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -20,7 +20,6 @@ package com.viaversion.viabackwards.protocol.v1_11to1_10;
 
 import com.viaversion.viabackwards.api.BackwardsProtocol;
 import com.viaversion.viabackwards.api.data.BackwardsMappingData;
-import com.viaversion.viabackwards.api.rewriters.SoundRewriter;
 import com.viaversion.viabackwards.api.rewriters.text.JsonNBTComponentRewriter;
 import com.viaversion.viabackwards.protocol.v1_11to1_10.rewriter.BlockItemPacketRewriter1_11;
 import com.viaversion.viabackwards.protocol.v1_11to1_10.rewriter.EntityPacketRewriter1_11;
@@ -51,18 +50,14 @@ public class Protocol1_11To1_10 extends BackwardsProtocol<ClientboundPackets1_9_
         itemRewriter.register();
         PlayerPacketRewriter1_11.register(this);
 
-        SoundRewriter<ClientboundPackets1_9_3> soundRewriter = new SoundRewriter<>(this);
-        soundRewriter.registerNamedSound(ClientboundPackets1_9_3.CUSTOM_SOUND);
-        soundRewriter.registerSound(ClientboundPackets1_9_3.SOUND);
-
         componentRewriter = new JsonNBTComponentRewriter<>(this, ComponentRewriterBase.ReadType.JSON);
         componentRewriter.registerComponentPacket(ClientboundPackets1_9_3.CHAT);
     }
 
     @Override
     public void init(UserConnection user) {
-        user.addEntityTracker(this.getClass(), new EntityTrackerBase(user, EntityTypes1_11.EntityType.PLAYER));
-        user.addClientWorld(this.getClass(), new ClientWorld());
+        addEntityTracker(user, new EntityTrackerBase(user, EntityTypes1_11.EntityType.PLAYER));
+        user.storables(this).setClientWorld(new ClientWorld());
 
         if (!user.has(WindowTracker.class)) {
             user.put(new WindowTracker());
@@ -84,12 +79,8 @@ public class Protocol1_11To1_10 extends BackwardsProtocol<ClientboundPackets1_9_
         return itemRewriter;
     }
 
+    @Override
     public JsonNBTComponentRewriter<ClientboundPackets1_9_3> getComponentRewriter() {
         return componentRewriter;
     }
-
-    @Override
-    public boolean hasMappingDataToLoad() {
-        return true;
-    }
 }

common/src/main/java/com/viaversion/viabackwards/protocol/v1_11to1_10/data/SplashPotionMappings1_10.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -22,27 +22,39 @@ import com.viaversion.viaversion.libs.fastutil.ints.Int2IntOpenHashMap;
 
 public class SplashPotionMappings1_10 {
 
-    private static final Int2IntMap DATA = new Int2IntOpenHashMap(14, 0.99F);
+    private static final Int2IntMap DATA = new Int2IntOpenHashMap(26, 0.99F);
 
     static {
         DATA.defaultReturnValue(-1);
-        DATA.put(2039713, 5); // night vision
-        DATA.put(8356754, 7); // invisibility
-        DATA.put(2293580, 9); // jump boost
-        DATA.put(14981690, 12); // fire resistance
-        DATA.put(8171462, 14); // swiftness
-        DATA.put(5926017, 17); // slowness
-        DATA.put(3035801, 19); // water breathing
-        DATA.put(16262179, 21); // instant health
-        DATA.put(4393481, 23); // instant damage
-        DATA.put(5149489, 25); // poison
-        DATA.put(13458603, 28); // regeneration
-        DATA.put(9643043, 31); // strength
-        DATA.put(4738376, 34); // weakness
-        DATA.put(3381504, 36); // luck
+        DATA.put(0x1F1FA1, 5); // night vision
+        DATA.put(0xC2FF66, 5); // night vision 1.19.4
+        DATA.put(0x7F8392, 7); // invisibility
+        DATA.put(0xF6F6F6, 7); // invisibility 1.19.4
+        DATA.put(0x22FF4C, 9); // jump boost
+        DATA.put(0xFDFF84, 9); // jump boost 1.19.4
+        DATA.put(0xE49A3A, 12); // fire resistance
+        DATA.put(0xFF9900, 12); // fire resistance 1.19.4
+        DATA.put(0x7CAFC6, 14); // swiftness
+        DATA.put(0x33EBFF, 14); // swiftness 1.19.4
+        DATA.put(0x5A6C81, 17); // slowness
+        DATA.put(0x8BAFE0, 17); // slowness 1.19.4
+        DATA.put(0x2E5299, 19); // water breathing
+        DATA.put(0x98DAC0, 19); // water breathing 1.19.4
+        DATA.put(0xF82423, 21); // instant health
+        DATA.put(0x430A09, 23); // instant damage
+        DATA.put(0xA9656A, 23); // instant damage 1.19.4
+        DATA.put(0x4E9331, 25); // poison
+        DATA.put(0x87A363, 25); // poison 1.19.4
+        DATA.put(0xCD5CAB, 28); // regeneration
+        DATA.put(0x932423, 31); // strength
+        DATA.put(0xFFC700, 31); // strength 1.19.4
+        DATA.put(0x484D48, 34); // weakness
+        DATA.put(0x339900, 36); // luck
+        DATA.put(0x59C106, 36); // luck 1.19.4
     }
 
     public static int getOldData(int data) {
-        return DATA.get(data);
+        // newer servers send as ARGB
+        return DATA.get(data & 0xFFFFFF);
     }
 }

common/src/main/java/com/viaversion/viabackwards/protocol/v1_11to1_10/rewriter/BlockItemPacketRewriter1_11.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -18,6 +18,8 @@
 
 package com.viaversion.viabackwards.protocol.v1_11to1_10.rewriter;
 
+import com.viaversion.nbt.tag.CompoundTag;
+import com.viaversion.nbt.tag.StringTag;
 import com.viaversion.viabackwards.api.data.MappedLegacyBlockItem;
 import com.viaversion.viabackwards.api.rewriters.LegacyBlockItemRewriter;
 import com.viaversion.viabackwards.api.rewriters.LegacyEnchantmentRewriter;
@@ -26,7 +28,7 @@ import com.viaversion.viabackwards.protocol.v1_11to1_10.storage.ChestedHorseStor
 import com.viaversion.viabackwards.protocol.v1_11to1_10.storage.WindowTracker;
 import com.viaversion.viaversion.api.connection.UserConnection;
 import com.viaversion.viaversion.api.data.entity.EntityTracker;
-import com.viaversion.viaversion.api.data.entity.StoredEntityData;
+import com.viaversion.viaversion.api.data.entity.TrackedEntity;
 import com.viaversion.viaversion.api.minecraft.ClientWorld;
 import com.viaversion.viaversion.api.minecraft.chunks.Chunk;
 import com.viaversion.viaversion.api.minecraft.entities.EntityTypes1_11;
@@ -35,12 +37,9 @@ import com.viaversion.viaversion.api.minecraft.item.Item;
 import com.viaversion.viaversion.api.protocol.remapper.PacketHandlers;
 import com.viaversion.viaversion.api.type.Types;
 import com.viaversion.viaversion.api.type.types.chunk.ChunkType1_9_3;
-import com.viaversion.nbt.tag.CompoundTag;
-import com.viaversion.nbt.tag.StringTag;
 import com.viaversion.viaversion.protocols.v1_10to1_11.data.EntityMappings1_11;
 import com.viaversion.viaversion.protocols.v1_9_1to1_9_3.packet.ClientboundPackets1_9_3;
 import com.viaversion.viaversion.protocols.v1_9_1to1_9_3.packet.ServerboundPackets1_9_3;
-import com.viaversion.viaversion.util.IdAndData;
 import java.util.Arrays;
 import java.util.Optional;
 
@@ -147,7 +146,7 @@ public class BlockItemPacketRewriter1_11 extends LegacyBlockItemRewriter<Clientb
         registerSetCreativeModeSlot(ServerboundPackets1_9_3.SET_CREATIVE_MODE_SLOT);
 
         protocol.registerClientbound(ClientboundPackets1_9_3.LEVEL_CHUNK, wrapper -> {
-            ClientWorld clientWorld = wrapper.user().getClientWorld(Protocol1_11To1_10.class);
+            ClientWorld clientWorld = wrapper.user().storables(protocol).clientWorld();
 
             ChunkType1_9_3 type = ChunkType1_9_3.forEnvironment(clientWorld.getEnvironment()); // Use the 1.10 Chunk type since nothing changed.
             Chunk chunk = wrapper.passthrough(type);
@@ -252,7 +251,7 @@ public class BlockItemPacketRewriter1_11 extends LegacyBlockItemRewriter<Clientb
     @Override
     protected void registerRewrites() {
         // Handle spawner block entity (map to itself with custom handler)
-        MappedLegacyBlockItem data = itemReplacements.computeIfAbsent(IdAndData.toRawData(52), s -> new MappedLegacyBlockItem(52));
+        MappedLegacyBlockItem data = blockReplacements.computeIfAbsent(compress(52, -1), s -> new MappedLegacyBlockItem(52, (short) -1, null, MappedLegacyBlockItem.Type.BLOCK));
         data.setBlockEntityHandler((b, tag) -> EntityMappings1_11.toClientSpawner(tag, true));
 
         enchantmentRewriter = new LegacyEnchantmentRewriter(nbtTagName());
@@ -280,7 +279,7 @@ public class BlockItemPacketRewriter1_11 extends LegacyBlockItemRewriter<Clientb
     @Override
     public Item handleItemToServer(UserConnection connection, Item item) {
         if (item == null) return null;
-        super.handleItemToServer(connection, item);
+        item = super.handleItemToServer(connection, item);
 
         CompoundTag tag = item.tag();
         if (tag == null) return item;
@@ -295,9 +294,9 @@ public class BlockItemPacketRewriter1_11 extends LegacyBlockItemRewriter<Clientb
     private boolean isLlama(UserConnection user) {
         WindowTracker tracker = user.get(WindowTracker.class);
         if (tracker.getInventory() != null && tracker.getInventory().equals("EntityHorse")) {
-            EntityTracker entTracker = user.getEntityTracker(Protocol1_11To1_10.class);
-            StoredEntityData entityData = entTracker.entityData(tracker.getEntityId());
-            return entityData != null && entityData.type().is(EntityTypes1_11.EntityType.LLAMA);
+            EntityTracker entTracker = user.getEntityTracker(protocol);
+            TrackedEntity entityData = entTracker.entity(tracker.getEntityId());
+            return entityData != null && entityData.entityType().is(EntityTypes1_11.EntityType.LLAMA);
         }
         return false;
     }
@@ -305,8 +304,8 @@ public class BlockItemPacketRewriter1_11 extends LegacyBlockItemRewriter<Clientb
     private Optional<ChestedHorseStorage> getChestedHorse(UserConnection user) {
         WindowTracker tracker = user.get(WindowTracker.class);
         if (tracker.getInventory() != null && tracker.getInventory().equals("EntityHorse")) {
-            EntityTracker entTracker = user.getEntityTracker(Protocol1_11To1_10.class);
-            StoredEntityData entityData = entTracker.entityData(tracker.getEntityId());
+            EntityTracker entTracker = user.getEntityTracker(protocol);
+            TrackedEntity entityData = entTracker.entity(tracker.getEntityId());
             if (entityData != null)
                 return Optional.of(entityData.get(ChestedHorseStorage.class));
         }

common/src/main/java/com/viaversion/viabackwards/protocol/v1_11to1_10/rewriter/EntityPacketRewriter1_11.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -23,14 +23,12 @@ import com.viaversion.viabackwards.api.rewriters.LegacyEntityRewriter;
 import com.viaversion.viabackwards.protocol.v1_11to1_10.Protocol1_11To1_10;
 import com.viaversion.viabackwards.protocol.v1_11to1_10.data.SplashPotionMappings1_10;
 import com.viaversion.viabackwards.protocol.v1_11to1_10.storage.ChestedHorseStorage;
-import com.viaversion.viaversion.api.data.entity.StoredEntityData;
 import com.viaversion.viaversion.api.minecraft.entities.EntityType;
 import com.viaversion.viaversion.api.minecraft.entities.EntityTypes1_11;
 import com.viaversion.viaversion.api.minecraft.entitydata.EntityData;
 import com.viaversion.viaversion.api.minecraft.entitydata.types.EntityDataTypes1_9;
 import com.viaversion.viaversion.api.protocol.remapper.PacketHandlers;
 import com.viaversion.viaversion.api.type.Types;
-import com.viaversion.viaversion.api.type.types.version.Types1_9;
 import com.viaversion.viaversion.protocols.v1_9_1to1_9_3.packet.ClientboundPackets1_9_3;
 import java.util.List;
 
@@ -104,17 +102,17 @@ public class EntityPacketRewriter1_11 extends LegacyEntityRewriter<ClientboundPa
                 map(Types.SHORT); // 9 - Velocity X
                 map(Types.SHORT); // 10 - Velocity Y
                 map(Types.SHORT); // 11 - Velocity Z
-                map(Types1_9.ENTITY_DATA_LIST); // 12 - Entity data
+                map(Types.ENTITY_DATA_LIST1_9); // 12 - Entity data
 
                 // Track entity
                 handler(getTrackerHandler(Types.UNSIGNED_BYTE, 0));
 
                 // Rewrite entity type / data
-                handler(getMobSpawnRewriter(Types1_9.ENTITY_DATA_LIST));
+                handler(getMobSpawnRewriter(Types.ENTITY_DATA_LIST1_9));
 
                 // Sub 1.11 clients will error if the list is empty
                 handler(wrapper -> {
-                    List<EntityData> entityDataList = wrapper.get(Types1_9.ENTITY_DATA_LIST, 0);
+                    List<EntityData> entityDataList = wrapper.get(Types.ENTITY_DATA_LIST1_9, 0);
                     if (entityDataList.isEmpty()) {
                         entityDataList.add(new EntityData(0, EntityDataTypes1_9.BYTE, (byte) 0));
                     }
@@ -136,12 +134,12 @@ public class EntityPacketRewriter1_11 extends LegacyEntityRewriter<ClientboundPa
                 map(Types.DOUBLE); // 4 - Z
                 map(Types.BYTE); // 5 - Yaw
                 map(Types.BYTE); // 6 - Pitch
-                map(Types1_9.ENTITY_DATA_LIST); // 7 - Entity data list
+                map(Types.ENTITY_DATA_LIST1_9); // 7 - Entity data list
 
-                handler(getTrackerAndDataHandler(Types1_9.ENTITY_DATA_LIST, EntityTypes1_11.EntityType.PLAYER));
+                handler(getTrackerAndDataHandler(Types.ENTITY_DATA_LIST1_9, EntityTypes1_11.EntityType.PLAYER));
                 handler(wrapper -> {
                     // Sub 1.11 clients will cry if the list is empty
-                    List<EntityData> entityDataList = wrapper.get(Types1_9.ENTITY_DATA_LIST, 0);
+                    List<EntityData> entityDataList = wrapper.get(Types.ENTITY_DATA_LIST1_9, 0);
                     if (entityDataList.isEmpty()) {
                         entityDataList.add(new EntityData(0, EntityDataTypes1_9.BYTE, (byte) 0));
                     }
@@ -150,7 +148,7 @@ public class EntityPacketRewriter1_11 extends LegacyEntityRewriter<ClientboundPa
         });
 
         registerRemoveEntities(ClientboundPackets1_9_3.REMOVE_ENTITIES);
-        registerSetEntityData(ClientboundPackets1_9_3.SET_ENTITY_DATA, Types1_9.ENTITY_DATA_LIST);
+        registerSetEntityData(ClientboundPackets1_9_3.SET_ENTITY_DATA, Types.ENTITY_DATA_LIST1_9);
 
         protocol.registerClientbound(ClientboundPackets1_9_3.ENTITY_EVENT, new PacketHandlers() {
             @Override
@@ -260,9 +258,9 @@ public class EntityPacketRewriter1_11 extends LegacyEntityRewriter<ClientboundPa
 
         // Handle horse flags
         filter().type(EntityTypes1_11.EntityType.ABSTRACT_HORSE).index(13).handler((event, data) -> {
-            StoredEntityData entityData = storedEntityData(event);
             byte b = (byte) data.getValue();
-            if (entityData.has(ChestedHorseStorage.class) && entityData.get(ChestedHorseStorage.class).isChested()) {
+            final ChestedHorseStorage chestedHorseStorage = event.trackedEntity().get(ChestedHorseStorage.class);
+            if (chestedHorseStorage != null && chestedHorseStorage.isChested()) {
                 b |= 0x08; // Chested
                 data.setValue(b);
             }
@@ -270,9 +268,8 @@ public class EntityPacketRewriter1_11 extends LegacyEntityRewriter<ClientboundPa
 
         // Create chested horse storage
         filter().type(EntityTypes1_11.EntityType.CHESTED_HORSE).handler((event, data) -> {
-            StoredEntityData entityData = storedEntityData(event);
-            if (!entityData.has(ChestedHorseStorage.class)) {
-                entityData.put(new ChestedHorseStorage());
+            if (!event.trackedEntity().has(ChestedHorseStorage.class)) {
+                event.trackedEntity().put(new ChestedHorseStorage());
             }
         });
 
@@ -281,8 +278,7 @@ public class EntityPacketRewriter1_11 extends LegacyEntityRewriter<ClientboundPa
 
         // Handle chested horse
         filter().type(EntityTypes1_11.EntityType.CHESTED_HORSE).index(15).handler((event, data) -> {
-            StoredEntityData entityData = storedEntityData(event);
-            ChestedHorseStorage storage = entityData.get(ChestedHorseStorage.class);
+            ChestedHorseStorage storage = event.trackedEntity().get(ChestedHorseStorage.class);
             boolean b = (boolean) data.getValue();
             storage.setChested(b);
             event.cancel();
@@ -290,8 +286,7 @@ public class EntityPacketRewriter1_11 extends LegacyEntityRewriter<ClientboundPa
 
         // Get rid of Liama entity data
         filter().type(EntityTypes1_11.EntityType.LLAMA).handler((event, data) -> {
-            StoredEntityData entityData = storedEntityData(event);
-            ChestedHorseStorage storage = entityData.get(ChestedHorseStorage.class);
+            ChestedHorseStorage storage = event.trackedEntity().get(ChestedHorseStorage.class);
 
             int index = event.index();
             // Store them for later (:

common/src/main/java/com/viaversion/viabackwards/protocol/v1_11to1_10/rewriter/PlayerPacketRewriter1_11.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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

common/src/main/java/com/viaversion/viabackwards/protocol/v1_11to1_10/storage/ChestedHorseStorage.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -18,7 +18,9 @@
 
 package com.viaversion.viabackwards.protocol.v1_11to1_10.storage;
 
-public class ChestedHorseStorage {
+import com.viaversion.viaversion.api.connection.StorableObject;
+
+public final class ChestedHorseStorage implements StorableObject {
     private boolean chested;
     private int liamaStrength;
     private int liamaCarpetColor = -1;

common/src/main/java/com/viaversion/viabackwards/protocol/v1_11to1_10/storage/WindowTracker.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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

common/src/main/java/com/viaversion/viabackwards/protocol/v1_12_1to1_12/Protocol1_12_1To1_12.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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

common/src/main/java/com/viaversion/viabackwards/protocol/v1_12_2to1_12_1/Protocol1_12_2To1_12_1.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -21,7 +21,6 @@ package com.viaversion.viabackwards.protocol.v1_12_2to1_12_1;
 import com.viaversion.viabackwards.api.BackwardsProtocol;
 import com.viaversion.viabackwards.protocol.v1_12_2to1_12_1.storage.KeepAliveTracker;
 import com.viaversion.viaversion.api.connection.UserConnection;
-import com.viaversion.viaversion.api.protocol.remapper.PacketHandlers;
 import com.viaversion.viaversion.api.type.Types;
 import com.viaversion.viaversion.protocols.v1_12to1_12_1.packet.ClientboundPackets1_12_1;
 import com.viaversion.viaversion.protocols.v1_12to1_12_1.packet.ServerboundPackets1_12_1;
@@ -34,32 +33,20 @@ public class Protocol1_12_2To1_12_1 extends BackwardsProtocol<ClientboundPackets
 
     @Override
     protected void registerPackets() {
-        registerClientbound(ClientboundPackets1_12_1.KEEP_ALIVE, new PacketHandlers() {
-            @Override
-            public void register() {
-                handler(packetWrapper -> {
-                    Long keepAlive = packetWrapper.read(Types.LONG);
-                    packetWrapper.user().get(KeepAliveTracker.class).setKeepAlive(keepAlive);
-                    packetWrapper.write(Types.VAR_INT, keepAlive.hashCode());
-                });
-            }
+        registerClientbound(ClientboundPackets1_12_1.KEEP_ALIVE, wrapper -> {
+            long keepAlive = wrapper.read(Types.LONG);
+            int id = wrapper.user().get(KeepAliveTracker.class).track(keepAlive);
+            wrapper.write(Types.VAR_INT, id);
         });
 
-        registerServerbound(ServerboundPackets1_12_1.KEEP_ALIVE, new PacketHandlers() {
-            @Override
-            public void register() {
-                handler(packetWrapper -> {
-                    int keepAlive = packetWrapper.read(Types.VAR_INT);
-                    long realKeepAlive = packetWrapper.user().get(KeepAliveTracker.class).getKeepAlive();
-                    if (keepAlive != Long.hashCode(realKeepAlive)) {
-                        packetWrapper.cancel(); // Wrong data, cancel packet
-                        return;
-                    }
-                    packetWrapper.write(Types.LONG, realKeepAlive);
-                    // Reset KeepAliveTracker (to prevent sending same valid value in a row causing a timeout)
-                    packetWrapper.user().get(KeepAliveTracker.class).setKeepAlive(Integer.MAX_VALUE);
-                });
+        registerServerbound(ServerboundPackets1_12_1.KEEP_ALIVE, wrapper -> {
+            int keepAlive = wrapper.read(Types.VAR_INT);
+            Long realKeepAlive = wrapper.user().get(KeepAliveTracker.class).consume(keepAlive);
+            if (realKeepAlive == null) {
+                wrapper.cancel(); // stale/bad
+                return;
             }
+            wrapper.write(Types.LONG, realKeepAlive);
         });
     }
 

common/src/main/java/com/viaversion/viabackwards/protocol/v1_12_2to1_12_1/storage/KeepAliveTracker.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -19,20 +19,22 @@
 package com.viaversion.viabackwards.protocol.v1_12_2to1_12_1.storage;
 
 import com.viaversion.viaversion.api.connection.StorableObject;
+import java.util.HashMap;
+import java.util.Map;
+import org.checkerframework.checker.nullness.qual.Nullable;
 
 public class KeepAliveTracker implements StorableObject {
-    private long keepAlive = Integer.MAX_VALUE;
 
-    public long getKeepAlive() {
-        return keepAlive;
+    private final Map<Integer, Long> pending = new HashMap<>();
+    private int nextId;
+
+    public int track(long original) {
+        int id = nextId++;
+        pending.put(id, original);
+        return id;
     }
 
-    public void setKeepAlive(long keepAlive) {
-        this.keepAlive = keepAlive;
-    }
-
-    @Override
-    public String toString() {
-        return "KeepAliveTracker{" + "keepAlive=" + keepAlive + '}';
+    public @Nullable Long consume(int id) {
+        return pending.remove(id);
     }
 }

common/src/main/java/com/viaversion/viabackwards/protocol/v1_12to1_11_1/Protocol1_12To1_11_1.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -20,11 +20,11 @@ package com.viaversion.viabackwards.protocol.v1_12to1_11_1;
 
 import com.viaversion.viabackwards.api.BackwardsProtocol;
 import com.viaversion.viabackwards.api.data.BackwardsMappingData;
-import com.viaversion.viabackwards.protocol.v1_12to1_11_1.storage.ShoulderTracker;
 import com.viaversion.viabackwards.protocol.v1_12to1_11_1.rewriter.BlockItemPacketRewriter1_12;
 import com.viaversion.viabackwards.protocol.v1_12to1_11_1.rewriter.ComponentRewriter1_12;
 import com.viaversion.viabackwards.protocol.v1_12to1_11_1.rewriter.EntityPacketRewriter1_12;
 import com.viaversion.viabackwards.protocol.v1_12to1_11_1.rewriter.SoundPacketRewriter1_12;
+import com.viaversion.viabackwards.protocol.v1_12to1_11_1.storage.ShoulderTracker;
 import com.viaversion.viaversion.api.connection.UserConnection;
 import com.viaversion.viaversion.api.minecraft.ClientWorld;
 import com.viaversion.viaversion.api.minecraft.entities.EntityTypes1_12;
@@ -50,8 +50,8 @@ public class Protocol1_12To1_11_1 extends BackwardsProtocol<ClientboundPackets1_
 
     @Override
     protected void registerPackets() {
-        itemRewriter.register();
-        entityRewriter.register();
+        super.registerPackets();
+
         componentRewriter.registerComponentPacket(ClientboundPackets1_12.CHAT);
         new SoundPacketRewriter1_12(this).register();
 
@@ -71,8 +71,8 @@ public class Protocol1_12To1_11_1 extends BackwardsProtocol<ClientboundPackets1_
 
     @Override
     public void init(UserConnection user) {
-        user.addEntityTracker(this.getClass(), new EntityTrackerBase(user, EntityTypes1_12.EntityType.PLAYER));
-        user.addClientWorld(this.getClass(), new ClientWorld());
+        addEntityTracker(user, new EntityTrackerBase(user, EntityTypes1_12.EntityType.PLAYER));
+        user.storables(this).setClientWorld(new ClientWorld());
 
         user.put(new ShoulderTracker(user));
     }
@@ -92,12 +92,8 @@ public class Protocol1_12To1_11_1 extends BackwardsProtocol<ClientboundPackets1_
         return itemRewriter;
     }
 
+    @Override
     public ComponentRewriter1_12 getComponentRewriter() {
         return componentRewriter;
     }
-
-    @Override
-    public boolean hasMappingDataToLoad() {
-        return true;
-    }
 }

common/src/main/java/com/viaversion/viabackwards/protocol/v1_12to1_11_1/data/BlockColors1_11_1.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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

common/src/main/java/com/viaversion/viabackwards/protocol/v1_12to1_11_1/data/MapColorMappings1_11_1.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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

common/src/main/java/com/viaversion/viabackwards/protocol/v1_12to1_11_1/rewriter/BlockItemPacketRewriter1_12.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -18,7 +18,13 @@
 
 package com.viaversion.viabackwards.protocol.v1_12to1_11_1.rewriter;
 
+import com.google.common.primitives.Ints;
+import com.viaversion.nbt.tag.CompoundTag;
+import com.viaversion.nbt.tag.IntArrayTag;
+import com.viaversion.nbt.tag.ListTag;
+import com.viaversion.nbt.tag.LongArrayTag;
 import com.viaversion.nbt.tag.StringTag;
+import com.viaversion.nbt.tag.Tag;
 import com.viaversion.viabackwards.api.rewriters.LegacyBlockItemRewriter;
 import com.viaversion.viabackwards.protocol.v1_12to1_11_1.Protocol1_12To1_11_1;
 import com.viaversion.viabackwards.protocol.v1_12to1_11_1.data.MapColorMappings1_11_1;
@@ -30,18 +36,14 @@ import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
 import com.viaversion.viaversion.api.protocol.remapper.PacketHandlers;
 import com.viaversion.viaversion.api.type.Types;
 import com.viaversion.viaversion.api.type.types.chunk.ChunkType1_9_3;
-import com.viaversion.nbt.tag.CompoundTag;
-import com.viaversion.nbt.tag.IntArrayTag;
-import com.viaversion.nbt.tag.LongArrayTag;
-import com.viaversion.nbt.tag.Tag;
 import com.viaversion.viaversion.protocols.v1_11_1to1_12.packet.ClientboundPackets1_12;
 import com.viaversion.viaversion.protocols.v1_11_1to1_12.packet.ServerboundPackets1_12;
 import com.viaversion.viaversion.protocols.v1_9_1to1_9_3.packet.ServerboundPackets1_9_3;
-import java.util.Iterator;
-import java.util.Map;
 import com.viaversion.viaversion.util.ComponentUtil;
 import com.viaversion.viaversion.util.Key;
 import com.viaversion.viaversion.util.SerializerVersion;
+import java.util.Iterator;
+import java.util.Map;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
 public class BlockItemPacketRewriter1_12 extends LegacyBlockItemRewriter<ClientboundPackets1_12, ServerboundPackets1_9_3, Protocol1_12To1_11_1> {
@@ -114,7 +116,7 @@ public class BlockItemPacketRewriter1_12 extends LegacyBlockItemRewriter<Clientb
                         PacketWrapper confirm = wrapper.create(ServerboundPackets1_12.CONTAINER_ACK);
                         confirm.write(Types.BYTE, wrapper.get(Types.BYTE, 0));
                         confirm.write(Types.SHORT, wrapper.get(Types.SHORT, 1));
-                        confirm.write(Types.BOOLEAN, false); // Success - not used
+                        confirm.write(Types.BOOLEAN, true); // Success - not used
 
                         wrapper.sendToServer(Protocol1_12To1_11_1.class);
                         wrapper.cancel();
@@ -131,7 +133,7 @@ public class BlockItemPacketRewriter1_12 extends LegacyBlockItemRewriter<Clientb
         registerSetCreativeModeSlot(ServerboundPackets1_9_3.SET_CREATIVE_MODE_SLOT);
 
         protocol.registerClientbound(ClientboundPackets1_12.LEVEL_CHUNK, wrapper -> {
-            ClientWorld clientWorld = wrapper.user().getClientWorld(Protocol1_12To1_11_1.class);
+            ClientWorld clientWorld = wrapper.user().storables(protocol).clientWorld();
 
             ChunkType1_9_3 type = ChunkType1_9_3.forEnvironment(clientWorld.getEnvironment()); // Use the 1.9.4 Chunk type since nothing changed.
             Chunk chunk = wrapper.passthrough(type);
@@ -230,6 +232,30 @@ public class BlockItemPacketRewriter1_12 extends LegacyBlockItemRewriter<Clientb
                 backupTag.put(entry.getKey(), fromLongArrayTag(tag));
                 iterator.remove();
                 hasLongArrayTag = true;
+            } else if (entry.getValue() instanceof ListTag<?> tag) {
+                if (tag.getElementType() == LongArrayTag.class) {
+                    // Lists can't hold mixed tag types, so the whole list has to be removed
+                    ListTag<IntArrayTag> intArrays = new ListTag<>(IntArrayTag.class);
+                    for (Tag longArrayTag : tag) {
+                        intArrays.add(fromLongArrayTag((LongArrayTag) longArrayTag));
+                    }
+                    backupTag.put(entry.getKey(), intArrays);
+                    iterator.remove();
+                    hasLongArrayTag = true;
+                } else if (tag.getElementType() == CompoundTag.class) {
+                    // Backed up by list index
+                    CompoundTag listBackupTag = new CompoundTag();
+                    for (int i = 0; i < tag.size(); i++) {
+                        CompoundTag nestedBackupTag = new CompoundTag();
+                        if (handleNbtToClient((CompoundTag) tag.get(i), nestedBackupTag)) {
+                            listBackupTag.put(Integer.toString(i), nestedBackupTag);
+                        }
+                    }
+                    if (!listBackupTag.isEmpty()) {
+                        backupTag.put(entry.getKey(), listBackupTag);
+                        hasLongArrayTag = true;
+                    }
+                }
             }
         }
         return hasLongArrayTag;
@@ -238,7 +264,7 @@ public class BlockItemPacketRewriter1_12 extends LegacyBlockItemRewriter<Clientb
     @Override
     public @Nullable Item handleItemToServer(UserConnection connection, Item item) {
         if (item == null) return null;
-        super.handleItemToServer(connection, item);
+        item = super.handleItemToServer(connection, item);
 
         if (item.tag() != null) {
             if (item.tag().remove("Via|LongArrayTags") instanceof CompoundTag tag) {
@@ -252,11 +278,33 @@ public class BlockItemPacketRewriter1_12 extends LegacyBlockItemRewriter<Clientb
     private void handleNbtToServer(CompoundTag compoundTag, CompoundTag backupTag) {
         // Restore the removed long array tags
         for (Map.Entry<String, Tag> entry : backupTag) {
-            if (entry.getValue() instanceof CompoundTag) {
-                CompoundTag nestedTag = compoundTag.getCompoundTag(entry.getKey());
-                handleNbtToServer(nestedTag, (CompoundTag) entry.getValue());
-            } else {
-                compoundTag.put(entry.getKey(), fromIntArrayTag((IntArrayTag) entry.getValue()));
+            if (entry.getValue() instanceof CompoundTag nestedBackupTag) {
+                Tag tag = compoundTag.get(entry.getKey());
+                if (tag instanceof CompoundTag nestedTag) {
+                    handleNbtToServer(nestedTag, nestedBackupTag);
+                } else if (tag instanceof ListTag<?> listTag) {
+                    handleListToServer(listTag, nestedBackupTag);
+                }
+            } else if (entry.getValue() instanceof IntArrayTag intArrayTag) {
+                compoundTag.put(entry.getKey(), fromIntArrayTag(intArrayTag));
+            } else if (entry.getValue() instanceof ListTag<?> intArrays) {
+                ListTag<LongArrayTag> longArrays = new ListTag<>(LongArrayTag.class);
+                for (Tag intArrayTag : intArrays) {
+                    if (intArrayTag instanceof IntArrayTag) {
+                        longArrays.add(fromIntArrayTag((IntArrayTag) intArrayTag));
+                    }
+                }
+                compoundTag.put(entry.getKey(), longArrays);
+            }
+        }
+    }
+
+    private void handleListToServer(ListTag<?> listTag, CompoundTag backupTag) {
+        for (Map.Entry<String, Tag> entry : backupTag) {
+            Integer index = Ints.tryParse(entry.getKey());
+            if (index != null && index >= 0 && index < listTag.size()
+                && listTag.get(index) instanceof CompoundTag nestedTag && entry.getValue() instanceof CompoundTag nestedBackupTag) {
+                handleNbtToServer(nestedTag, nestedBackupTag);
             }
         }
     }
@@ -275,7 +323,7 @@ public class BlockItemPacketRewriter1_12 extends LegacyBlockItemRewriter<Clientb
     private LongArrayTag fromIntArrayTag(IntArrayTag tag) {
         long[] longArray = new long[tag.length() / 2];
         int[] intArray = tag.getValue();
-        for (int i = 0, j = 0; i < intArray.length; i += 2, j++) {
+        for (int i = 0, j = 0; j < longArray.length; i += 2, j++) {
             longArray[j] = (long) intArray[i] << 32 | ((long) intArray[i + 1] & 0xFFFFFFFFL);
         }
         return new LongArrayTag(longArray);

common/src/main/java/com/viaversion/viabackwards/protocol/v1_12to1_11_1/rewriter/ComponentRewriter1_12.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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

common/src/main/java/com/viaversion/viabackwards/protocol/v1_12to1_11_1/rewriter/EntityPacketRewriter1_12.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -23,7 +23,6 @@ import com.viaversion.viabackwards.api.rewriters.LegacyEntityRewriter;
 import com.viaversion.viabackwards.protocol.v1_12to1_11_1.Protocol1_12To1_11_1;
 import com.viaversion.viabackwards.protocol.v1_12to1_11_1.storage.ParrotStorage;
 import com.viaversion.viabackwards.protocol.v1_12to1_11_1.storage.ShoulderTracker;
-import com.viaversion.viaversion.api.data.entity.StoredEntityData;
 import com.viaversion.viaversion.api.minecraft.entities.EntityType;
 import com.viaversion.viaversion.api.minecraft.entities.EntityTypes1_12;
 import com.viaversion.viaversion.api.minecraft.entitydata.EntityData;
@@ -31,8 +30,6 @@ import com.viaversion.viaversion.api.minecraft.entitydata.types.EntityDataTypes1
 import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
 import com.viaversion.viaversion.api.protocol.remapper.PacketHandlers;
 import com.viaversion.viaversion.api.type.Types;
-import com.viaversion.viaversion.api.type.types.version.Types1_12;
-import com.viaversion.viaversion.api.type.types.version.Types1_9;
 import com.viaversion.viaversion.libs.gson.JsonElement;
 import com.viaversion.viaversion.protocols.v1_11_1to1_12.packet.ClientboundPackets1_12;
 import com.viaversion.viaversion.protocols.v1_9_1to1_9_3.packet.ClientboundPackets1_9_3;
@@ -84,13 +81,13 @@ public class EntityPacketRewriter1_12 extends LegacyEntityRewriter<ClientboundPa
                 map(Types.SHORT); // 9 - Velocity X
                 map(Types.SHORT); // 10 - Velocity Y
                 map(Types.SHORT); // 11 - Velocity Z
-                map(Types1_12.ENTITY_DATA_LIST, Types1_9.ENTITY_DATA_LIST); // 12 - Entity data
+                map(Types.ENTITY_DATA_LIST1_12, Types.ENTITY_DATA_LIST1_9); // 12 - Entity data
 
                 // Track entity
                 handler(getTrackerHandler());
 
                 // Rewrite entity type / data
-                handler(getMobSpawnRewriter1_11(Types1_9.ENTITY_DATA_LIST));
+                handler(getMobSpawnRewriter1_11(Types.ENTITY_DATA_LIST1_9));
             }
         });
 
@@ -106,9 +103,9 @@ public class EntityPacketRewriter1_12 extends LegacyEntityRewriter<ClientboundPa
                 map(Types.DOUBLE); // 4 - Z
                 map(Types.BYTE); // 5 - Yaw
                 map(Types.BYTE); // 6 - Pitch
-                map(Types1_12.ENTITY_DATA_LIST, Types1_9.ENTITY_DATA_LIST); // 7 - Entity data list
+                map(Types.ENTITY_DATA_LIST1_12, Types.ENTITY_DATA_LIST1_9); // 7 - Entity data list
 
-                handler(getTrackerAndDataHandler(Types1_9.ENTITY_DATA_LIST, EntityTypes1_12.EntityType.PLAYER));
+                handler(getTrackerAndDataHandler(Types.ENTITY_DATA_LIST1_9, EntityTypes1_12.EntityType.PLAYER));
             }
         });
 
@@ -120,7 +117,7 @@ public class EntityPacketRewriter1_12 extends LegacyEntityRewriter<ClientboundPa
                 map(Types.INT); // 2 - Dimension
 
                 handler(getDimensionHandler(1));
-                handler(getPlayerTrackerHandler());
+                handler(playerTrackerHandler());
 
                 handler(wrapper -> {
                     ShoulderTracker tracker = wrapper.user().get(ShoulderTracker.class);
@@ -142,7 +139,7 @@ public class EntityPacketRewriter1_12 extends LegacyEntityRewriter<ClientboundPa
 
         registerRespawn(ClientboundPackets1_12.RESPAWN);
         registerRemoveEntities(ClientboundPackets1_12.REMOVE_ENTITIES);
-        registerSetEntityData(ClientboundPackets1_12.SET_ENTITY_DATA, Types1_12.ENTITY_DATA_LIST, Types1_9.ENTITY_DATA_LIST);
+        registerSetEntityData(ClientboundPackets1_12.SET_ENTITY_DATA, Types.ENTITY_DATA_LIST1_12, Types.ENTITY_DATA_LIST1_9);
 
         protocol.registerClientbound(ClientboundPackets1_12.UPDATE_ATTRIBUTES, new PacketHandlers() {
             @Override
@@ -210,16 +207,14 @@ public class EntityPacketRewriter1_12 extends LegacyEntityRewriter<ClientboundPa
 
         // Create Parrot storage
         filter().type(EntityTypes1_12.EntityType.PARROT).handler((event, data) -> {
-            StoredEntityData entityData = storedEntityData(event);
-            if (!entityData.has(ParrotStorage.class)) {
-                entityData.put(new ParrotStorage());
+            if (!event.trackedEntity().has(ParrotStorage.class)) {
+                event.trackedEntity().put(new ParrotStorage());
             }
         });
         // Parrot remove animal entity data
         filter().type(EntityTypes1_12.EntityType.PARROT).cancel(12); // Is baby
         filter().type(EntityTypes1_12.EntityType.PARROT).index(13).handler((event, data) -> {
-            StoredEntityData entityData = storedEntityData(event);
-            ParrotStorage storage = entityData.get(ParrotStorage.class);
+            ParrotStorage storage = event.trackedEntity().get(ParrotStorage.class);
             boolean isSitting = (((byte) data.getValue()) & 0x01) == 0x01;
             boolean isTamed = (((byte) data.getValue()) & 0x04) == 0x04;
 

common/src/main/java/com/viaversion/viabackwards/protocol/v1_12to1_11_1/rewriter/SoundPacketRewriter1_12.java

@@ -1,6 +1,6 @@
 /*
  * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
- * Copyright (C) 2016-2025 ViaVersion and contributors
+ * 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
@@ -21,7 +21,6 @@ package com.viaversion.viabackwards.protocol.v1_12to1_11_1.rewriter;
 import com.viaversion.viabackwards.api.rewriters.LegacySoundRewriter;
 import com.viaversion.viabackwards.protocol.v1_12to1_11_1.Protocol1_12To1_11_1;
 import com.viaversion.viaversion.api.protocol.remapper.PacketHandlers;
-import com.viaversion.viaversion.api.type.Type;
 import com.viaversion.viaversion.api.type.Types;
 import com.viaversion.viaversion.protocols.v1_11_1to1_12.packet.ClientboundPackets1_12;
 
@@ -33,20 +32,7 @@ public class SoundPacketRewriter1_12 extends LegacySoundRewriter<Protocol1_12To1
 
     @Override
     protected void registerPackets() {
-        protocol.registerClientbound(ClientboundPackets1_12.CUSTOM_SOUND, new PacketHandlers() {
-            @Override
-            public void register() {
-                map(Types.STRING); // 0 - Sound name
-                map(Types.VAR_INT); // 1 - Sound Category
-                map(Types.INT); // 2 - x
-                map(Types.INT); // 3 - y
-                map(Types.INT); // 4 - z
-                map(Types.FLOAT); // 5 - Volume
-                map(Types.FLOAT); // 6 - Pitch
-            }
-        });
-
-        protocol.registerClientbound(ClientboundPackets1_12.SOUND, new PacketHandlers() {
+        protocol.replaceClientbound(ClientboundPackets1_12.SOUND, new PacketHandlers() {
             @Override
             public void register() {
                 map(Types.VAR_INT); // 0 - Sound name