diff --git a/common/src/main/java/us/myles/ViaVersion/api/protocol/ProtocolPipeline.java b/common/src/main/java/us/myles/ViaVersion/api/protocol/ProtocolPipeline.java
index 01bf4286d..8e4473599 100644
--- a/common/src/main/java/us/myles/ViaVersion/api/protocol/ProtocolPipeline.java
+++ b/common/src/main/java/us/myles/ViaVersion/api/protocol/ProtocolPipeline.java
@@ -75,7 +75,7 @@ public class ProtocolPipeline extends SimpleProtocol {
         packetWrapper.apply(direction, state, 0, protocolList, direction == Direction.OUTGOING);
         super.transform(direction, state, packetWrapper);
 
-        if (Via.getManager().isDebug()) { // 26 52 76
+        if (Via.getManager().isDebug()) {
             logPacket(direction, state, packetWrapper, originalID);
         }
     }
diff --git a/common/src/main/java/us/myles/ViaVersion/protocols/protocol1_17to1_16_4/Protocol1_17To1_16_4.java b/common/src/main/java/us/myles/ViaVersion/protocols/protocol1_17to1_16_4/Protocol1_17To1_16_4.java
index 74e182362..25bc63aa9 100644
--- a/common/src/main/java/us/myles/ViaVersion/protocols/protocol1_17to1_16_4/Protocol1_17To1_16_4.java
+++ b/common/src/main/java/us/myles/ViaVersion/protocols/protocol1_17to1_16_4/Protocol1_17To1_16_4.java
@@ -2,6 +2,7 @@ package us.myles.ViaVersion.protocols.protocol1_17to1_16_4;
 
 import org.jetbrains.annotations.Nullable;
 import us.myles.ViaVersion.api.data.MappingData;
+import us.myles.ViaVersion.api.data.UserConnection;
 import us.myles.ViaVersion.api.protocol.Protocol;
 import us.myles.ViaVersion.api.remapper.PacketRemapper;
 import us.myles.ViaVersion.api.rewriters.RegistryType;
@@ -13,10 +14,11 @@ import us.myles.ViaVersion.protocols.protocol1_16_2to1_16_1.ClientboundPackets1_
 import us.myles.ViaVersion.protocols.protocol1_16_2to1_16_1.ServerboundPackets1_16_2;
 import us.myles.ViaVersion.protocols.protocol1_17to1_16_4.packets.InventoryPackets;
 import us.myles.ViaVersion.protocols.protocol1_17to1_16_4.packets.WorldPackets;
+import us.myles.ViaVersion.protocols.protocol1_17to1_16_4.storage.BiomeStorage;
 
 public class Protocol1_17To1_16_4 extends Protocol<ClientboundPackets1_16_2, ClientboundPackets1_16_2, ServerboundPackets1_16_2, ServerboundPackets1_16_2> {
 
-    public static final MappingData MAPPINGS = new MappingData("1.16.2", "1.17");
+    public static final MappingData MAPPINGS = new MappingData("1.16.2", "1.17", true);
     private TagRewriter tagRewriter;
 
     public Protocol1_17To1_16_4() {
@@ -56,6 +58,11 @@ public class Protocol1_17To1_16_4 extends Protocol<ClientboundPackets1_16_2, Cli
         tagRewriter.addTag(RegistryType.BLOCK, "minecraft:cauldrons", 261);
     }
 
+    @Override
+    public void init(UserConnection user) {
+        user.put(new BiomeStorage(user));
+    }
+
     @Override
     @Nullable
     public MappingData getMappingData() {
diff --git a/common/src/main/java/us/myles/ViaVersion/protocols/protocol1_17to1_16_4/packets/WorldPackets.java b/common/src/main/java/us/myles/ViaVersion/protocols/protocol1_17to1_16_4/packets/WorldPackets.java
index 8bc4fc608..01be93aac 100644
--- a/common/src/main/java/us/myles/ViaVersion/protocols/protocol1_17to1_16_4/packets/WorldPackets.java
+++ b/common/src/main/java/us/myles/ViaVersion/protocols/protocol1_17to1_16_4/packets/WorldPackets.java
@@ -1,5 +1,6 @@
 package us.myles.ViaVersion.protocols.protocol1_17to1_16_4.packets;
 
+import us.myles.ViaVersion.api.Via;
 import us.myles.ViaVersion.api.minecraft.chunks.Chunk;
 import us.myles.ViaVersion.api.minecraft.chunks.ChunkSection;
 import us.myles.ViaVersion.api.remapper.PacketRemapper;
@@ -8,6 +9,7 @@ import us.myles.ViaVersion.api.type.Type;
 import us.myles.ViaVersion.protocols.protocol1_16_2to1_16_1.ClientboundPackets1_16_2;
 import us.myles.ViaVersion.protocols.protocol1_16_2to1_16_1.types.Chunk1_16_2Type;
 import us.myles.ViaVersion.protocols.protocol1_17to1_16_4.Protocol1_17To1_16_4;
+import us.myles.ViaVersion.protocols.protocol1_17to1_16_4.storage.BiomeStorage;
 import us.myles.ViaVersion.protocols.protocol1_17to1_16_4.types.Chunk1_17Type;
 
 public class WorldPackets {
@@ -43,9 +45,18 @@ public class WorldPackets {
                     Chunk chunk = wrapper.read(new Chunk1_16_2Type());
                     wrapper.write(new Chunk1_17Type(), chunk);
 
-                    if (!chunk.isFullChunk()) {
-                        chunk.setBiomeData(new int[0]);
-                        //TODO does this have to be converted to a multi block change and/or entity nbt update?
+                    BiomeStorage biomeStorage = wrapper.user().get(BiomeStorage.class);
+                    if (chunk.isFullChunk()) {
+                        biomeStorage.setBiomes(chunk.getX(), chunk.getZ(), chunk.getBiomeData());
+                    } else {
+                        // Biomes always have to be sent now
+                        int[] biomes = biomeStorage.getBiomes(chunk.getX(), chunk.getZ());
+                        if (biomes != null) {
+                            chunk.setBiomeData(biomes);
+                        } else {
+                            Via.getPlatform().getLogger().warning("Biome data not found for chunk at " + chunk.getX() + ", " + chunk.getZ());
+                            chunk.setBiomeData(new int[0]);
+                        }
                     }
 
                     for (int s = 0; s < 16; s++) {
@@ -60,6 +71,17 @@ public class WorldPackets {
             }
         });
 
+        protocol.registerOutgoing(ClientboundPackets1_16_2.UNLOAD_CHUNK, new PacketRemapper() {
+            @Override
+            public void registerMap() {
+                handler(wrapper -> {
+                    int x = wrapper.passthrough(Type.INT);
+                    int z = wrapper.passthrough(Type.INT);
+                    wrapper.user().get(BiomeStorage.class).clearBiomes(x, z);
+                });
+            }
+        });
+
         blockRewriter.registerEffect(ClientboundPackets1_16_2.EFFECT, 1010, 2001);
     }
 }
diff --git a/common/src/main/java/us/myles/ViaVersion/protocols/protocol1_17to1_16_4/storage/BiomeStorage.java b/common/src/main/java/us/myles/ViaVersion/protocols/protocol1_17to1_16_4/storage/BiomeStorage.java
new file mode 100644
index 000000000..2ce38a8c4
--- /dev/null
+++ b/common/src/main/java/us/myles/ViaVersion/protocols/protocol1_17to1_16_4/storage/BiomeStorage.java
@@ -0,0 +1,34 @@
+package us.myles.ViaVersion.protocols.protocol1_17to1_16_4.storage;
+
+import org.jetbrains.annotations.Nullable;
+import us.myles.ViaVersion.api.data.StoredObject;
+import us.myles.ViaVersion.api.data.UserConnection;
+
+import java.util.HashMap;
+import java.util.Map;
+
+public class BiomeStorage extends StoredObject {
+
+    private final Map<Long, int[]> chunkBiomes = new HashMap<>();
+
+    public BiomeStorage(UserConnection user) {
+        super(user);
+    }
+
+    @Nullable
+    public int[] getBiomes(int x, int z) {
+        return chunkBiomes.get(getChunkSectionIndex(x, z));
+    }
+
+    public void setBiomes(int x, int z, int[] biomes) {
+        chunkBiomes.put(getChunkSectionIndex(x, z), biomes);
+    }
+
+    public void clearBiomes(int x, int z) {
+        chunkBiomes.remove(getChunkSectionIndex(x, z));
+    }
+
+    private long getChunkSectionIndex(int x, int z) {
+        return ((x & 0x3FFFFFFL) << 38) | (z & 0x3FFFFFFL);
+    }
+}
diff --git a/common/src/main/resources/assets/viaversion/data/mappingdiff-1.16.2to1.17.json b/common/src/main/resources/assets/viaversion/data/mappingdiff-1.16.2to1.17.json
index ae013c97b..fd030bf58 100644
--- a/common/src/main/resources/assets/viaversion/data/mappingdiff-1.16.2to1.17.json
+++ b/common/src/main/resources/assets/viaversion/data/mappingdiff-1.16.2to1.17.json
@@ -1,10 +1,61 @@
 {
+  "blocks": {
+    "498": "dirt_path"
+  },
   "blockstates": {
-    "4729": "minecraft:chain[axis=y,waterlogged=true]",
-    "4730": "minecraft:chain[axis=y,waterlogged=false]",
-    "14886": "minecraft:lantern[hanging=true,waterlogged=false]",
-    "14887": "minecraft:lantern[hanging=false,waterlogged=false]",
-    "14888": "minecraft:soul_lantern[hanging=true,waterlogged=false]",
-    "14889": "minecraft:soul_lantern[hanging=false,waterlogged=false]"
+    "1305": "minecraft:powered_rail[powered=true,shape=north_south,waterlogged=false]",
+    "1306": "minecraft:powered_rail[powered=true,shape=east_west,waterlogged=false]",
+    "1307": "minecraft:powered_rail[powered=true,shape=ascending_east,waterlogged=false]",
+    "1308": "minecraft:powered_rail[powered=true,shape=ascending_west,waterlogged=false]",
+    "1309": "minecraft:powered_rail[powered=true,shape=ascending_north,waterlogged=false]",
+    "1310": "minecraft:powered_rail[powered=true,shape=ascending_south,waterlogged=false]",
+    "1311": "minecraft:powered_rail[powered=false,shape=north_south,waterlogged=false]",
+    "1312": "minecraft:powered_rail[powered=false,shape=east_west,waterlogged=false]",
+    "1313": "minecraft:powered_rail[powered=false,shape=ascending_east,waterlogged=false]",
+    "1314": "minecraft:powered_rail[powered=false,shape=ascending_west,waterlogged=false]",
+    "1315": "minecraft:powered_rail[powered=false,shape=ascending_north,waterlogged=false]",
+    "1316": "minecraft:powered_rail[powered=false,shape=ascending_south,waterlogged=false]",
+    "1317": "minecraft:detector_rail[powered=true,shape=north_south,waterlogged=false]",
+    "1318": "minecraft:detector_rail[powered=true,shape=east_west,waterlogged=false]",
+    "1319": "minecraft:detector_rail[powered=true,shape=ascending_east,waterlogged=false]",
+    "1320": "minecraft:detector_rail[powered=true,shape=ascending_west,waterlogged=false]",
+    "1321": "minecraft:detector_rail[powered=true,shape=ascending_north,waterlogged=false]",
+    "1322": "minecraft:detector_rail[powered=true,shape=ascending_south,waterlogged=false]",
+    "1323": "minecraft:detector_rail[powered=false,shape=north_south,waterlogged=false]",
+    "1324": "minecraft:detector_rail[powered=false,shape=east_west,waterlogged=false]",
+    "1325": "minecraft:detector_rail[powered=false,shape=ascending_east,waterlogged=false]",
+    "1326": "minecraft:detector_rail[powered=false,shape=ascending_west,waterlogged=false]",
+    "1327": "minecraft:detector_rail[powered=false,shape=ascending_north,waterlogged=false]",
+    "1328": "minecraft:detector_rail[powered=false,shape=ascending_south,waterlogged=false]",
+    "3645": "minecraft:rail[shape=north_south,waterlogged=false]",
+    "3646": "minecraft:rail[shape=east_west,waterlogged=false]",
+    "3647": "minecraft:rail[shape=ascending_east,waterlogged=false]",
+    "3648": "minecraft:rail[shape=ascending_west,waterlogged=false]",
+    "3649": "minecraft:rail[shape=ascending_north,waterlogged=false]",
+    "3650": "minecraft:rail[shape=ascending_south,waterlogged=false]",
+    "3651": "minecraft:rail[shape=south_east,waterlogged=false]",
+    "3652": "minecraft:rail[shape=south_west,waterlogged=false]",
+    "3653": "minecraft:rail[shape=north_west,waterlogged=false]",
+    "3654": "minecraft:rail[shape=north_east,waterlogged=false]",
+    "6827": "minecraft:activator_rail[powered=true,shape=north_south,waterlogged=false]",
+    "6828": "minecraft:activator_rail[powered=true,shape=east_west,waterlogged=false]",
+    "6829": "minecraft:activator_rail[powered=true,shape=ascending_east,waterlogged=false]",
+    "6830": "minecraft:activator_rail[powered=true,shape=ascending_west,waterlogged=false]",
+    "6831": "minecraft:activator_rail[powered=true,shape=ascending_north,waterlogged=false]",
+    "6832": "minecraft:activator_rail[powered=true,shape=ascending_south,waterlogged=false]",
+    "6833": "minecraft:activator_rail[powered=false,shape=north_south,waterlogged=false]",
+    "6834": "minecraft:activator_rail[powered=false,shape=east_west,waterlogged=false]",
+    "6835": "minecraft:activator_rail[powered=false,shape=ascending_east,waterlogged=false]",
+    "6836": "minecraft:activator_rail[powered=false,shape=ascending_west,waterlogged=false]",
+    "6837": "minecraft:activator_rail[powered=false,shape=ascending_north,waterlogged=false]",
+    "6838": "minecraft:activator_rail[powered=false,shape=ascending_south,waterlogged=false]",
+    "5145": "minecraft:cauldron",
+    "5146": "minecraft:water_cauldron[level=1]",
+    "5147": "minecraft:water_cauldron[level=2]",
+    "5148": "minecraft:water_cauldron[level=3]",
+    "9227": "minecraft:dirt_path"
+  },
+  "items": {
+    "372": "minecraft:dirt_path"
   }
 }
\ No newline at end of file