diff --git a/pom.xml b/pom.xml
index d5a31597..51b72c1e 100644
--- a/pom.xml
+++ b/pom.xml
@@ -5,7 +5,7 @@
 
     <groupId>com.github.steveice10</groupId>
     <artifactId>mcprotocollib</artifactId>
-    <version>20w20b-SNAPSHOT</version>
+    <version>20w21a-SNAPSHOT</version>
     <packaging>jar</packaging>
 
     <name>MCProtocolLib</name>
diff --git a/src/main/java/com/github/steveice10/mc/protocol/MinecraftConstants.java b/src/main/java/com/github/steveice10/mc/protocol/MinecraftConstants.java
index cc1e40eb..752a53fd 100644
--- a/src/main/java/com/github/steveice10/mc/protocol/MinecraftConstants.java
+++ b/src/main/java/com/github/steveice10/mc/protocol/MinecraftConstants.java
@@ -2,8 +2,8 @@ package com.github.steveice10.mc.protocol;
 
 public class MinecraftConstants {
     // General Constants
-    public static final String GAME_VERSION = "20w20b";
-    public static final int PROTOCOL_VERSION = 717;
+    public static final String GAME_VERSION = "20w21a";
+    public static final int PROTOCOL_VERSION = 718;
 
     // General Key Constants
     public static final String PROFILE_KEY = "profile";
diff --git a/src/main/java/com/github/steveice10/mc/protocol/packet/ingame/server/ServerChatPacket.java b/src/main/java/com/github/steveice10/mc/protocol/packet/ingame/server/ServerChatPacket.java
index df4c1b11..f825c4a0 100644
--- a/src/main/java/com/github/steveice10/mc/protocol/packet/ingame/server/ServerChatPacket.java
+++ b/src/main/java/com/github/steveice10/mc/protocol/packet/ingame/server/ServerChatPacket.java
@@ -14,6 +14,7 @@ import lombok.NonNull;
 import lombok.Setter;
 
 import java.io.IOException;
+import java.util.UUID;
 
 @Data
 @Setter(AccessLevel.NONE)
@@ -22,6 +23,7 @@ import java.io.IOException;
 public class ServerChatPacket implements Packet {
     private @NonNull Message message;
     private @NonNull MessageType type;
+    private @NonNull UUID senderUuid;
 
     public ServerChatPacket(@NonNull String text) {
         this(Message.fromString(text));
@@ -32,19 +34,29 @@ public class ServerChatPacket implements Packet {
     }
 
     public ServerChatPacket(@NonNull String text, @NonNull MessageType type) {
-        this(Message.fromString(text), type);
+        this(Message.fromString(text), type, new UUID(0, 0));
+    }
+
+    public ServerChatPacket(@NonNull Message message, @NonNull MessageType type) {
+        this(message, type, new UUID(0, 0));
+    }
+
+    public ServerChatPacket(@NonNull String text, @NonNull MessageType type, UUID uuid) {
+        this(Message.fromString(text), type, uuid);
     }
 
     @Override
     public void read(NetInput in) throws IOException {
         this.message = Message.fromString(in.readString());
         this.type = MagicValues.key(MessageType.class, in.readByte());
+        this.senderUuid = in.readUUID();
     }
 
     @Override
     public void write(NetOutput out) throws IOException {
         out.writeString(this.message.toJsonString());
         out.writeByte(MagicValues.value(Integer.class, this.type));
+        out.writeUUID(this.senderUuid);
     }
 
     @Override
diff --git a/src/main/java/com/github/steveice10/mc/protocol/packet/ingame/server/ServerJoinGamePacket.java b/src/main/java/com/github/steveice10/mc/protocol/packet/ingame/server/ServerJoinGamePacket.java
index e251b12c..98a51eed 100644
--- a/src/main/java/com/github/steveice10/mc/protocol/packet/ingame/server/ServerJoinGamePacket.java
+++ b/src/main/java/com/github/steveice10/mc/protocol/packet/ingame/server/ServerJoinGamePacket.java
@@ -1,7 +1,9 @@
 package com.github.steveice10.mc.protocol.packet.ingame.server;
 
 import com.github.steveice10.mc.protocol.data.MagicValues;
+import com.github.steveice10.mc.protocol.data.game.NBT;
 import com.github.steveice10.mc.protocol.data.game.entity.player.GameMode;
+import com.github.steveice10.opennbt.tag.builtin.CompoundTag;
 import com.github.steveice10.packetlib.io.NetInput;
 import com.github.steveice10.packetlib.io.NetOutput;
 import com.github.steveice10.packetlib.packet.Packet;
@@ -25,7 +27,8 @@ public class ServerJoinGamePacket implements Packet {
     private int entityId;
     private boolean hardcore;
     private @NonNull GameMode gameMode;
-    private int dimension;
+    private @NonNull CompoundTag dimensionCodec;
+    private @NonNull String dimension;
     private long hashedSeed;
     private int maxPlayers;
     private int viewDistance;
@@ -41,8 +44,8 @@ public class ServerJoinGamePacket implements Packet {
         int gameMode = in.readUnsignedByte();
         this.hardcore = (gameMode & GAMEMODE_FLAG_HARDCORE) != 0;
         this.gameMode = MagicValues.key(GameMode.class, gameMode & GAMEMODE_MASK);
-
-        this.dimension = in.readInt();
+        this.dimensionCodec = NBT.read(in);
+        this.dimension = in.readString();
         this.hashedSeed = in.readLong();
         this.maxPlayers = in.readUnsignedByte();
         this.viewDistance = in.readVarInt();
@@ -62,8 +65,8 @@ public class ServerJoinGamePacket implements Packet {
         }
 
         out.writeByte(gameMode);
-
-        out.writeInt(this.dimension);
+        NBT.write(out, this.dimensionCodec);
+        out.writeString(this.dimension);
         out.writeLong(this.hashedSeed);
         out.writeByte(this.maxPlayers);
         out.writeVarInt(this.viewDistance);
diff --git a/src/main/java/com/github/steveice10/mc/protocol/packet/ingame/server/ServerRespawnPacket.java b/src/main/java/com/github/steveice10/mc/protocol/packet/ingame/server/ServerRespawnPacket.java
index 4b15ab07..9c10d269 100644
--- a/src/main/java/com/github/steveice10/mc/protocol/packet/ingame/server/ServerRespawnPacket.java
+++ b/src/main/java/com/github/steveice10/mc/protocol/packet/ingame/server/ServerRespawnPacket.java
@@ -19,7 +19,7 @@ import java.io.IOException;
 @NoArgsConstructor(access = AccessLevel.PRIVATE)
 @AllArgsConstructor
 public class ServerRespawnPacket implements Packet {
-    private int dimension;
+    private String dimension;
     private long hashedSeed;
     private @NonNull GameMode gamemode;
     private boolean debug;
@@ -28,7 +28,7 @@ public class ServerRespawnPacket implements Packet {
 
     @Override
     public void read(NetInput in) throws IOException {
-        this.dimension = in.readInt();
+        this.dimension = in.readString();
         this.hashedSeed = in.readLong();
         this.gamemode = MagicValues.key(GameMode.class, in.readUnsignedByte());
         this.debug = in.readBoolean();
@@ -38,7 +38,7 @@ public class ServerRespawnPacket implements Packet {
 
     @Override
     public void write(NetOutput out) throws IOException {
-        out.writeInt(this.dimension);
+        out.writeString(this.dimension);
         out.writeLong(this.hashedSeed);
         out.writeByte(MagicValues.value(Integer.class, this.gamemode));
         out.writeBoolean(this.debug);
diff --git a/src/test/java/com/github/steveice10/mc/protocol/MinecraftProtocolTest.java b/src/test/java/com/github/steveice10/mc/protocol/MinecraftProtocolTest.java
index 8e0f298f..97392696 100644
--- a/src/test/java/com/github/steveice10/mc/protocol/MinecraftProtocolTest.java
+++ b/src/test/java/com/github/steveice10/mc/protocol/MinecraftProtocolTest.java
@@ -9,6 +9,9 @@ import com.github.steveice10.mc.protocol.data.status.VersionInfo;
 import com.github.steveice10.mc.protocol.data.status.handler.ServerInfoBuilder;
 import com.github.steveice10.mc.protocol.data.status.handler.ServerInfoHandler;
 import com.github.steveice10.mc.protocol.packet.ingame.server.ServerJoinGamePacket;
+import com.github.steveice10.opennbt.tag.builtin.CompoundTag;
+import com.github.steveice10.opennbt.tag.builtin.ListTag;
+import com.github.steveice10.opennbt.tag.builtin.StringTag;
 import com.github.steveice10.packetlib.Client;
 import com.github.steveice10.packetlib.Server;
 import com.github.steveice10.packetlib.Session;
@@ -44,7 +47,7 @@ public class MinecraftProtocolTest {
             new TextMessage("Hello world!"),
             null
     );
-    private static final ServerJoinGamePacket JOIN_GAME_PACKET = new ServerJoinGamePacket(0, false, GameMode.SURVIVAL, 0, 100, 0, 16, false, false, false, false);
+    private static final ServerJoinGamePacket JOIN_GAME_PACKET = new ServerJoinGamePacket(0, false, GameMode.SURVIVAL, getDimensionTag(), "minecraft:overworld", 100, 0, 16, false, false, false, false);
 
     private static Server server;
 
@@ -139,4 +142,15 @@ public class MinecraftProtocolTest {
             }
         }
     }
+
+    private static CompoundTag getDimensionTag() {
+        CompoundTag tag = new CompoundTag("");
+        ListTag dimensionTag = new ListTag("dimension");
+        CompoundTag overworldTag = new CompoundTag("");
+        overworldTag.put(new StringTag("key", "minecraft:overworld"));
+        overworldTag.put(new StringTag("element", "minecraft:overworld"));
+        dimensionTag.add(overworldTag);
+        tag.put(tag);
+        return tag;
+    }
 }