diff --git a/src/main/java/net/hollowcube/polar/PolarReader.java b/src/main/java/net/hollowcube/polar/PolarReader.java
index 8b4c645..aff6bc4 100644
--- a/src/main/java/net/hollowcube/polar/PolarReader.java
+++ b/src/main/java/net/hollowcube/polar/PolarReader.java
@@ -74,9 +74,13 @@ private PolarReader() {}
                 continue;
 
             var packed = buffer.read(LONG_ARRAY);
-            var bitsPerEntry = packed.length * 64 / PolarChunk.HEIGHTMAP_SIZE;
-            heightmaps[i] = new int[PolarChunk.HEIGHTMAP_SIZE];
-            PaletteUtil.unpack(heightmaps[i], packed, bitsPerEntry);
+            if (packed.length == 0) {
+                heightmaps[i] = new int[0];
+            } else {
+                var bitsPerEntry = packed.length * 64 / PolarChunk.HEIGHTMAP_SIZE;
+                heightmaps[i] = new int[PolarChunk.HEIGHTMAP_SIZE];
+                PaletteUtil.unpack(heightmaps[i], packed, bitsPerEntry);
+            }
         }
 
         // Objects
diff --git a/src/main/java/net/hollowcube/polar/PolarWriter.java b/src/main/java/net/hollowcube/polar/PolarWriter.java
index 82a1c0f..b81205d 100644
--- a/src/main/java/net/hollowcube/polar/PolarWriter.java
+++ b/src/main/java/net/hollowcube/polar/PolarWriter.java
@@ -61,7 +61,8 @@ private static void writeChunk(@NotNull NetworkBuffer buffer, @NotNull PolarChun
             for (int i = 0; i < PolarChunk.MAX_HEIGHTMAPS; i++) {
                 var heightmap = chunk.heightmap(i);
                 if (heightmap == null) continue;
-                buffer.write(LONG_ARRAY, PaletteUtil.pack(heightmap, bitsPerEntry));
+                if (heightmap.length == 0) buffer.write(LONG_ARRAY, new long[0]);
+                else buffer.write(LONG_ARRAY, PaletteUtil.pack(heightmap, bitsPerEntry));
             }
         }