diff --git a/core/src/main/java/net/momirealms/craftengine/core/util/FriendlyByteBuf.java b/core/src/main/java/net/momirealms/craftengine/core/util/FriendlyByteBuf.java
index 7b298a6cd..e9b1c7de8 100644
--- a/core/src/main/java/net/momirealms/craftengine/core/util/FriendlyByteBuf.java
+++ b/core/src/main/java/net/momirealms/craftengine/core/util/FriendlyByteBuf.java
@@ -217,6 +217,20 @@ public class FriendlyByteBuf extends ByteBuf {
         return this;
     }
 
+    public FriendlyByteBuf writeFixedSizeLongArray(long[] array) {
+        for (long value : array) {
+            this.writeLong(value);
+        }
+        return this;
+    }
+
+    public long[] readFixedSizeLongArray(long[] output) {
+        for(int i = 0; i < output.length; ++i) {
+            output[i] = this.readLong();
+        }
+        return output;
+    }
+
     public long[] readLongArray() {
         return this.readLongArray(null);
     }
diff --git a/core/src/main/java/net/momirealms/craftengine/core/world/chunk/PalettedContainer.java b/core/src/main/java/net/momirealms/craftengine/core/world/chunk/PalettedContainer.java
index bc41daeec..da44b67e9 100644
--- a/core/src/main/java/net/momirealms/craftengine/core/world/chunk/PalettedContainer.java
+++ b/core/src/main/java/net/momirealms/craftengine/core/world/chunk/PalettedContainer.java
@@ -8,6 +8,7 @@ import net.momirealms.craftengine.core.plugin.CraftEngine;
 import net.momirealms.craftengine.core.util.FriendlyByteBuf;
 import net.momirealms.craftengine.core.util.IndexedIterable;
 import net.momirealms.craftengine.core.util.MCUtils;
+import net.momirealms.craftengine.core.util.VersionHelper;
 import org.jetbrains.annotations.Nullable;
 
 import java.util.Arrays;
@@ -15,12 +16,14 @@ import java.util.List;
 import java.util.Optional;
 import java.util.concurrent.locks.Lock;
 import java.util.concurrent.locks.ReentrantLock;
-import java.util.function.Consumer;
-import java.util.function.IntUnaryOperator;
-import java.util.function.Predicate;
+import java.util.function.*;
 import java.util.stream.LongStream;
 
 public class PalettedContainer<T> implements PaletteResizeListener<T>, ReadableContainer<T> {
+    private static final BiConsumer<FriendlyByteBuf, long[]> RAW_DATA_WRITER = VersionHelper.isVersionNewerThan1_21_5() ?
+            (FriendlyByteBuf::writeFixedSizeLongArray) : (FriendlyByteBuf::writeLongArray);
+    private static final BiConsumer<FriendlyByteBuf, long[]> RAW_DATA_READER = VersionHelper.isVersionNewerThan1_21_5() ?
+            (FriendlyByteBuf::readFixedSizeLongArray) : (FriendlyByteBuf::readLongArray);
     private final PaletteResizeListener<T> dummyListener = (newSize, added) -> 0;
     private final IndexedIterable<T> idList;
     private Data<T> data;
@@ -78,7 +81,7 @@ public class PalettedContainer<T> implements PaletteResizeListener<T>, ReadableC
             int i = buf.readByte();
             Data<T> data = this.getCompatibleData(this.data, i);
             data.palette.readPacket(buf);
-            buf.readLongArray(data.storage.getData());
+            RAW_DATA_READER.accept(buf, data.storage.getData());
             this.data = data;
         } finally {
             this.unlock();
@@ -303,7 +306,7 @@ public class PalettedContainer<T> implements PaletteResizeListener<T>, ReadableC
         public void writePacket(FriendlyByteBuf buf) {
             buf.writeByte(this.storage.getElementBits());
             this.palette.writePacket(buf);
-            buf.writeLongArray(this.storage.getData());
+            RAW_DATA_WRITER.accept(buf, this.storage.getData());
         }
     }