diff --git a/.github/workflows/buildtools.sh b/.github/workflows/buildtools.sh
index a512230..6905ff8 100644
--- a/.github/workflows/buildtools.sh
+++ b/.github/workflows/buildtools.sh
@@ -33,4 +33,5 @@ checkVersion "1.20.2" "17"
 checkVersion "1.20.4" "17"
 checkVersion "1.20.6" "21"
 checkVersion "1.21" "21"
-checkVersion "1.21.3" "21"
\ No newline at end of file
+checkVersion "1.21.3" "21"
+checkVersion "1.21.4" "21"
\ No newline at end of file
diff --git a/zip-common/src/main/java/net/imprex/zip/common/MinecraftVersion.java b/zip-common/src/main/java/net/imprex/zip/common/MinecraftVersion.java
index ba93bf1..af92975 100644
--- a/zip-common/src/main/java/net/imprex/zip/common/MinecraftVersion.java
+++ b/zip-common/src/main/java/net/imprex/zip/common/MinecraftVersion.java
@@ -19,6 +19,7 @@ private static final class NmsMapping {
 		private static final List<NmsMapping> MAPPINGS = new ArrayList<>();
 
 		static {
+			MAPPINGS.add(new NmsMapping("1.21.4", "v1_21_R3"));
 			MAPPINGS.add(new NmsMapping("1.21.3", "v1_21_R2"));
 			MAPPINGS.add(new NmsMapping("1.21", "v1_21_R1"));
 			MAPPINGS.add(new NmsMapping("1.20.5", "v1_20_R4"));
diff --git a/zip-nms/pom.xml b/zip-nms/pom.xml
index 486a581..2c1e80b 100644
--- a/zip-nms/pom.xml
+++ b/zip-nms/pom.xml
@@ -21,5 +21,6 @@
 		<module>zip-nms-v1_20_R4</module>
 		<module>zip-nms-v1_21_R1</module>
 		<module>zip-nms-v1_21_R2</module>
+		<module>zip-nms-v1_21_R3</module>
 	</modules>
 </project>
\ No newline at end of file
diff --git a/zip-nms/zip-nms-v1_21_R3/pom.xml b/zip-nms/zip-nms-v1_21_R3/pom.xml
new file mode 100644
index 0000000..89e6386
--- /dev/null
+++ b/zip-nms/zip-nms-v1_21_R3/pom.xml
@@ -0,0 +1,72 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+
+	<parent>
+		<groupId>net.imprex</groupId>
+		<artifactId>zip-nms</artifactId>
+		<version>${revision}</version>
+	</parent>
+
+	<artifactId>zip-nms-v1_21_R3</artifactId>
+
+	<dependencies>
+		<dependency>
+			<groupId>net.imprex</groupId>
+			<artifactId>zip-nms-api</artifactId>
+			<version>${revision}</version>
+			<scope>provided</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.spigotmc</groupId>
+			<artifactId>spigot</artifactId>
+			<version>1.21.4-R0.1-SNAPSHOT</version>
+			<classifier>remapped-mojang</classifier>
+			<scope>provided</scope>
+		</dependency>
+	</dependencies>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>net.md-5</groupId>
+				<artifactId>specialsource-maven-plugin</artifactId>
+				<version>${plugin.specialsource.version}</version>
+				<executions>
+					<execution>
+						<phase>package</phase>
+						<goals>
+							<goal>remap</goal>
+						</goals>
+						<id>remap-obf</id>
+						<configuration>
+							<srgIn>
+								org.spigotmc:minecraft-server:1.21.4-R0.1-SNAPSHOT:txt:maps-mojang</srgIn>
+							<reverse>true</reverse>
+							<remappedDependencies>
+								org.spigotmc:spigot:1.21.4-R0.1-SNAPSHOT:jar:remapped-mojang</remappedDependencies>
+							<remappedArtifactAttached>true</remappedArtifactAttached>
+							<remappedClassifierName>remapped-obf</remappedClassifierName>
+						</configuration>
+					</execution>
+					<execution>
+						<phase>package</phase>
+						<goals>
+							<goal>remap</goal>
+						</goals>
+						<id>remap-spigot</id>
+						<configuration>
+							<inputFile>
+								${project.build.directory}/${project.artifactId}-${project.version}-remapped-obf.jar</inputFile>
+							<srgIn>
+								org.spigotmc:minecraft-server:1.21.4-R0.1-SNAPSHOT:csrg:maps-spigot</srgIn>
+							<remappedDependencies>
+								org.spigotmc:spigot:1.21.4-R0.1-SNAPSHOT:jar:remapped-obf</remappedDependencies>
+						</configuration>
+					</execution>
+				</executions>
+			</plugin>
+		</plugins>
+	</build>
+</project>
\ No newline at end of file
diff --git a/zip-nms/zip-nms-v1_21_R3/src/main/java/net/imprex/zip/nms/v1_21_R3/ZipNmsManager.java b/zip-nms/zip-nms-v1_21_R3/src/main/java/net/imprex/zip/nms/v1_21_R3/ZipNmsManager.java
new file mode 100644
index 0000000..7c2a710
--- /dev/null
+++ b/zip-nms/zip-nms-v1_21_R3/src/main/java/net/imprex/zip/nms/v1_21_R3/ZipNmsManager.java
@@ -0,0 +1,150 @@
+package net.imprex.zip.nms.v1_21_R3;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Optional;
+import java.util.UUID;
+import java.util.function.BiConsumer;
+
+import org.bukkit.Material;
+import org.bukkit.craftbukkit.v1_21_R3.CraftRegistry;
+import org.bukkit.craftbukkit.v1_21_R3.inventory.CraftItemStack;
+import org.bukkit.inventory.ItemStack;
+import org.bukkit.inventory.meta.SkullMeta;
+
+import com.mojang.authlib.GameProfile;
+import com.mojang.authlib.properties.Property;
+
+import net.imprex.zip.common.ReflectionUtil;
+import net.imprex.zip.nms.api.NmsManager;
+import net.minecraft.core.RegistryAccess;
+import net.minecraft.nbt.CompoundTag;
+import net.minecraft.nbt.ListTag;
+import net.minecraft.nbt.NbtAccounter;
+import net.minecraft.nbt.NbtIo;
+import net.minecraft.nbt.Tag;
+import net.minecraft.world.item.component.ResolvableProfile;
+
+public class ZipNmsManager implements NmsManager {
+
+	private static final BiConsumer<SkullMeta, GameProfile> SET_PROFILE;
+
+	private static final RegistryAccess DEFAULT_REGISTRY = CraftRegistry.getMinecraftRegistry();
+
+	private static final CompoundTag NBT_EMPTY_ITEMSTACK = new CompoundTag();
+
+	static {
+		NBT_EMPTY_ITEMSTACK.putString("id", "minecraft:air");
+
+		BiConsumer<SkullMeta, GameProfile> setProfile = (meta, profile) -> {
+			throw new NullPointerException("Unable to find 'setProfile' method!");
+		};
+
+		Class<?> craftMetaSkullClass = new ItemStack(Material.PLAYER_HEAD)
+				.getItemMeta()
+				.getClass();
+
+		Method setResolvableProfileMethod = ReflectionUtil.searchMethod(craftMetaSkullClass, void.class, ResolvableProfile.class);
+		if (setResolvableProfileMethod != null) {
+			setProfile = (meta, profile) -> {
+				try {
+					setResolvableProfileMethod.invoke(meta, new ResolvableProfile(profile));
+				} catch (IllegalAccessException | InvocationTargetException e) {
+					e.printStackTrace();
+				}
+			};
+		} else {
+			Method setProfileMethod = ReflectionUtil.searchMethod(craftMetaSkullClass, void.class, GameProfile.class);
+			if (setProfileMethod != null) {
+				setProfile = (meta, profile) -> {
+					try {
+						setProfileMethod.invoke(meta, profile);
+					} catch (IllegalAccessException | InvocationTargetException e) {
+						e.printStackTrace();
+					}
+				};
+			}
+		}
+
+		SET_PROFILE = setProfile;
+	}
+
+	public byte[] nbtToBinary(CompoundTag compound) {
+		try (ByteArrayOutputStream outputStream = new ByteArrayOutputStream()) {
+			NbtIo.writeCompressed(compound, outputStream);
+			return outputStream.toByteArray();
+		} catch (Exception e) {
+			e.printStackTrace();
+		}
+		return null;
+	}
+
+	public CompoundTag binaryToNBT(byte[] binary) {
+		try (ByteArrayInputStream inputStream = new ByteArrayInputStream(binary)) {
+			return NbtIo.readCompressed(inputStream, NbtAccounter.unlimitedHeap());
+		} catch (Exception e) {
+			e.printStackTrace();
+		}
+		return new CompoundTag();
+	}
+
+	@Override
+	public byte[] itemstackToBinary(ItemStack[] items) {
+		CompoundTag inventory = new CompoundTag();
+		ListTag list = new ListTag();
+		for (ItemStack itemStack : items) {
+			if (itemStack == null || itemStack.getType() == Material.AIR) {
+				list.add(NBT_EMPTY_ITEMSTACK);
+			} else {
+				net.minecraft.world.item.ItemStack craftItem = CraftItemStack.asNMSCopy(itemStack);
+				Tag tag = craftItem.save(DEFAULT_REGISTRY);
+				list.add(tag);
+			}
+		}
+		inventory.put("i", list);
+		return nbtToBinary(inventory);
+	}
+
+	@Override
+	public List<ItemStack> binaryToItemStack(byte[] binary) {
+		CompoundTag nbt = binaryToNBT(binary);
+		List<ItemStack> items = new ArrayList<>();
+		if (nbt.contains("i", 9)) {
+			ListTag list = nbt.getList("i", 10);
+			for (Tag base : list) {
+				if (base instanceof CompoundTag itemTag) {
+					if (itemTag.getString("id").equals("minecraft:air")) {
+						items.add(new ItemStack(Material.AIR));
+					} else {
+						Optional<net.minecraft.world.item.ItemStack> optional = net.minecraft.world.item.ItemStack.parse(DEFAULT_REGISTRY, itemTag);
+						if (optional.isPresent()) {
+							items.add(CraftItemStack.asBukkitCopy(optional.get()));
+						}
+					}
+				}
+			}
+		}
+		return items;
+	}
+
+	@Override
+	public void setSkullProfile(SkullMeta meta, String texture) {
+		try {
+			GameProfile gameProfile = new GameProfile(UUID.randomUUID(), "");
+			gameProfile.getProperties().put("textures", new Property("textures", texture));
+
+			SET_PROFILE.accept(meta, gameProfile);
+		} catch (Exception e) {
+			e.printStackTrace();
+		}
+	}
+
+	@Override
+	public boolean isAir(Material material) {
+		return material == null || material == Material.AIR;
+	}
+}
\ No newline at end of file
diff --git a/zip-plugin/pom.xml b/zip-plugin/pom.xml
index 0b06ae0..967eac7 100644
--- a/zip-plugin/pom.xml
+++ b/zip-plugin/pom.xml
@@ -101,5 +101,11 @@
 			<version>${revision}</version>
 			<scope>compile</scope>
 		</dependency>
+		<dependency>
+			<groupId>net.imprex</groupId>
+			<artifactId>zip-nms-v1_21_R3</artifactId>
+			<version>${revision}</version>
+			<scope>compile</scope>
+		</dependency>
 	</dependencies>
 </project>
\ No newline at end of file