diff --git a/core/src/mindustry/maps/filters/TerrainFilter.java b/core/src/mindustry/maps/filters/TerrainFilter.java
index 4caea2041a..e5da12a52f 100644
--- a/core/src/mindustry/maps/filters/TerrainFilter.java
+++ b/core/src/mindustry/maps/filters/TerrainFilter.java
@@ -10,7 +10,7 @@ import static mindustry.maps.filters.FilterOption.*;
 
 public class TerrainFilter extends GenerateFilter{
     float scl = 40, threshold = 0.9f, octaves = 3f, falloff = 0.5f, magnitude = 1f, circleScl = 2.1f;
-    Block floor = Blocks.stone, block = Blocks.stoneWall;
+    Block floor = Blocks.air, block = Blocks.stoneWall;
 
     @Override
     public FilterOption[] options(){
@@ -21,7 +21,7 @@ public class TerrainFilter extends GenerateFilter{
         new SliderOption("circle-scale", () -> circleScl, f -> circleScl = f, 0f, 3f),
         new SliderOption("octaves", () -> octaves, f -> octaves = f, 1f, 10f),
         new SliderOption("falloff", () -> falloff, f -> falloff = f, 0f, 1f),
-        new BlockOption("floor", () -> floor, b -> floor = b, floorsOnly),
+        new BlockOption("floor", () -> floor, b -> floor = b, floorsOptional),
         new BlockOption("wall", () -> block, b -> block = b, wallsOnly)
         );
     }
@@ -30,12 +30,12 @@ public class TerrainFilter extends GenerateFilter{
     public void apply(){
         float noise = noise(in.x, in.y, scl, magnitude, octaves, falloff) + Mathf.dst((float)in.x / in.width, (float)in.y / in.height, 0.5f, 0.5f) * circleScl;
 
-        in.floor = floor;
+        if(floor != Blocks.air){
+            in.floor = floor;
+        }
 
         if(noise >= threshold){
             in.block = block;
-        }else if(!in.block.synthetic()){
-            in.block = Blocks.air;
         }
     }
 }