diff --git a/core/src/mindustry/content/Blocks.java b/core/src/mindustry/content/Blocks.java
index 3dfcb0a7a4..82810ac84b 100644
--- a/core/src/mindustry/content/Blocks.java
+++ b/core/src/mindustry/content/Blocks.java
@@ -302,6 +302,7 @@ public class Blocks implements ContentList{
 
         icerocks = new StaticWall("icerocks"){{
             variants = 2;
+            iceSnow.asFloor().wall = this;
         }};
 
         snowrocks = new StaticWall("snowrocks"){{
@@ -365,11 +366,13 @@ public class Blocks implements ContentList{
         moss = new Floor("moss"){{
             variants = 3;
             attributes.set(Attribute.spores, 0.15f);
+            wall = sporePine;
         }};
 
         sporeMoss = new Floor("spore-moss"){{
             variants = 3;
             attributes.set(Attribute.spores, 0.3f);
+            wall = sporerocks;
         }};
 
         metalFloor = new Floor("metal-floor"){{
diff --git a/core/src/mindustry/content/UnitTypes.java b/core/src/mindustry/content/UnitTypes.java
index e9421b71b6..407b16e6c7 100644
--- a/core/src/mindustry/content/UnitTypes.java
+++ b/core/src/mindustry/content/UnitTypes.java
@@ -17,6 +17,7 @@ public class UnitTypes implements ContentList{
     public static @EntityDef({Unitc.class}) UnitType spirit;
     public static @EntityDef({Unitc.class, Builderc.class}) UnitType phantom;
 
+    //TODO remove
     public static UnitType alpha, delta, tau, omega, dart, javelin, trident, glaive;
     public static UnitType starter;
 
diff --git a/core/src/mindustry/core/ContentLoader.java b/core/src/mindustry/core/ContentLoader.java
index d16f6a4279..2f662ef13b 100644
--- a/core/src/mindustry/core/ContentLoader.java
+++ b/core/src/mindustry/core/ContentLoader.java
@@ -233,6 +233,10 @@ public class ContentLoader{
         return (Block)getByID(ContentType.block, id);
     }
 
+    public Block block(String name){
+        return (Block)getByName(ContentType.block, name);
+    }
+
     public Array<Item> items(){
         return getBy(ContentType.item);
     }
diff --git a/core/src/mindustry/core/World.java b/core/src/mindustry/core/World.java
index dd7733e806..ca77b19017 100644
--- a/core/src/mindustry/core/World.java
+++ b/core/src/mindustry/core/World.java
@@ -7,7 +7,6 @@ import arc.math.geom.*;
 import arc.struct.*;
 import arc.util.ArcAnnotate.*;
 import arc.util.*;
-import mindustry.content.*;
 import mindustry.core.GameState.*;
 import mindustry.game.EventType.*;
 import mindustry.game.*;
@@ -69,11 +68,11 @@ public class World{
     }
 
     public int width(){
-        return tiles.width();
+        return tiles.width;
     }
 
     public int height(){
-        return tiles.height();
+        return tiles.height;
     }
 
     public int unitWidth(){
@@ -130,7 +129,7 @@ public class World{
     public Tiles resize(int width, int height){
         clearTileEntities();
 
-        if(tiles.width() != width || tiles.height() != height){
+        if(tiles.width != width || tiles.height != height){
             tiles = new Tiles(width, height);
         }
 
@@ -164,7 +163,7 @@ public class World{
             addDarkness(tiles);
         }
 
-        Groups.resize(-finalWorldBounds, -finalWorldBounds, tiles.width() * tilesize + finalWorldBounds * 2, tiles.height() * tilesize + finalWorldBounds * 2);
+        Groups.resize(-finalWorldBounds, -finalWorldBounds, tiles.width * tilesize + finalWorldBounds * 2, tiles.height * tilesize + finalWorldBounds * 2);
 
         generating = false;
         Events.fire(new WorldLoadEvent());
@@ -207,8 +206,7 @@ public class World{
                 sector.planet.generator.generate(position, gen);
                 tiles.set(x, y, new Tile(x, y, gen.floor, gen.overlay, gen.block));
             });
-
-            tiles.get(size/2, size/2).setBlock(Blocks.coreShard, Team.sharded);
+            sector.planet.generator.decorate(tiles);
         });
     }
 
@@ -300,8 +298,8 @@ public class World{
     }
 
     public void addDarkness(Tiles tiles){
-        byte[] dark = new byte[tiles.width() * tiles.height()];
-        byte[] writeBuffer = new byte[tiles.width() * tiles.height()];
+        byte[] dark = new byte[tiles.width * tiles.height];
+        byte[] writeBuffer = new byte[tiles.width * tiles.height];
 
         byte darkIterations = 4;
 
@@ -314,11 +312,11 @@ public class World{
 
         for(int i = 0; i < darkIterations; i++){
             for(Tile tile : tiles){
-                int idx = tile.y * tiles.width() + tile.x;
+                int idx = tile.y * tiles.width + tile.x;
                 boolean min = false;
                 for(Point2 point : Geometry.d4){
                     int newX = tile.x + point.x, newY = tile.y + point.y;
-                    int nidx = newY * tiles.width() + newX;
+                    int nidx = newY * tiles.width + newX;
                     if(tiles.in(newX, newY) && dark[nidx] < dark[idx]){
                         min = true;
                         break;
@@ -331,7 +329,7 @@ public class World{
         }
 
         for(Tile tile : tiles){
-            int idx = tile.y * tiles.width() + tile.x;
+            int idx = tile.y * tiles.width + tile.x;
 
             if(tile.isDarkened()){
                 tile.rotation(dark[idx]);
@@ -341,7 +339,7 @@ public class World{
                 boolean full = true;
                 for(Point2 p : Geometry.d4){
                     int px = p.x + tile.x, py = p.y + tile.y;
-                    int nidx = py * tiles.width() + px;
+                    int nidx = py * tiles.width + px;
                     if(tiles.in(px, py) && !(tile.isDarkened() && dark[nidx] == 4)){
                         full = false;
                         break;
diff --git a/core/src/mindustry/graphics/PlanetRenderer.java b/core/src/mindustry/graphics/PlanetRenderer.java
index 22bca19b4d..472d025b6d 100644
--- a/core/src/mindustry/graphics/PlanetRenderer.java
+++ b/core/src/mindustry/graphics/PlanetRenderer.java
@@ -120,4 +120,9 @@ public class PlanetRenderer implements PlanetGenerator{
     public void generate(Vec3 position, TileGen tile){
 
     }
+
+    @Override
+    public void decorate(Tiles tiles){
+
+    }
 }
diff --git a/core/src/mindustry/io/MapIO.java b/core/src/mindustry/io/MapIO.java
index 0a70a8c0f6..e1a9b3eefa 100644
--- a/core/src/mindustry/io/MapIO.java
+++ b/core/src/mindustry/io/MapIO.java
@@ -133,7 +133,7 @@ public class MapIO{
     }
 
     public static Pixmap generatePreview(Tiles tiles){
-        Pixmap pixmap = new Pixmap(tiles.width(), tiles.height(), Format.RGBA8888);
+        Pixmap pixmap = new Pixmap(tiles.width, tiles.height, Format.RGBA8888);
         for(int x = 0; x < pixmap.getWidth(); x++){
             for(int y = 0; y < pixmap.getHeight(); y++){
                 Tile tile = tiles.getn(x, y);
diff --git a/core/src/mindustry/maps/generators/BasicGenerator.java b/core/src/mindustry/maps/generators/BasicGenerator.java
index a4a22e1095..70d38a5541 100644
--- a/core/src/mindustry/maps/generators/BasicGenerator.java
+++ b/core/src/mindustry/maps/generators/BasicGenerator.java
@@ -182,7 +182,7 @@ public abstract class BasicGenerator extends RandomGenerator{
         Tile end = tiles.getn(endX, endY);
         GridBits closed = new GridBits(width, height);
         IntFloatMap costs = new IntFloatMap();
-        PriorityQueue<Tile> queue = new PriorityQueue<>(tiles.width() * tiles.height()/4, (a, b) -> Float.compare(costs.get(a.pos(), 0f) + dh.cost(a.x, a.y, end.x, end.y), costs.get(b.pos(), 0f) + dh.cost(b.x, b.y, end.x, end.y)));
+        PriorityQueue<Tile> queue = new PriorityQueue<>(tiles.width * tiles.height /4, (a, b) -> Float.compare(costs.get(a.pos(), 0f) + dh.cost(a.x, a.y, end.x, end.y), costs.get(b.pos(), 0f) + dh.cost(b.x, b.y, end.x, end.y)));
         queue.add(start);
         boolean found = false;
         while(!queue.isEmpty()){
diff --git a/core/src/mindustry/maps/generators/MapGenerator.java b/core/src/mindustry/maps/generators/MapGenerator.java
index 54e5469bc1..14a1a712ab 100644
--- a/core/src/mindustry/maps/generators/MapGenerator.java
+++ b/core/src/mindustry/maps/generators/MapGenerator.java
@@ -62,7 +62,7 @@ public class MapGenerator extends Generator{
         for(Tile tile : tiles){
             if(tile.overlay() == Blocks.spawn){
                 int rad = 10;
-                Geometry.circle(tile.x, tile.y, tiles.width(), tiles.height(), rad, (wx, wy) -> {
+                Geometry.circle(tile.x, tile.y, tiles.width, tiles.height, rad, (wx, wy) -> {
                     if(tile.overlay().itemDrop != null){
                         tile.clearOverlay();
                     }
diff --git a/core/src/mindustry/maps/generators/RandomGenerator.java b/core/src/mindustry/maps/generators/RandomGenerator.java
index ea8b0d15ad..cdafcedf43 100644
--- a/core/src/mindustry/maps/generators/RandomGenerator.java
+++ b/core/src/mindustry/maps/generators/RandomGenerator.java
@@ -20,11 +20,14 @@ public abstract class RandomGenerator extends Generator{
     public void generate(Tiles tiles){
         for(int x = 0; x < width; x++){
             for(int y = 0; y < height; y++){
-                floor = Blocks.air;
-                block = Blocks.air;
-                ore = Blocks.air;
+                Tile prev = tiles.getn(x, y);
+                floor = prev.floor();
+                block = prev.block();
+                ore = prev.overlay();
                 generate(x, y);
-                tiles.set(x, y, new Tile(x, y, floor, ore, block));
+                prev.setFloor(floor.asFloor());
+                prev.setBlock(block);
+                prev.setOverlay(ore);
             }
         }
 
diff --git a/core/src/mindustry/maps/planet/PlanetGenerator.java b/core/src/mindustry/maps/planet/PlanetGenerator.java
index e0635f5553..d03456a33d 100644
--- a/core/src/mindustry/maps/planet/PlanetGenerator.java
+++ b/core/src/mindustry/maps/planet/PlanetGenerator.java
@@ -8,4 +8,5 @@ public interface PlanetGenerator{
     float getHeight(Vec3 position);
     Color getColor(Vec3 position);
     void generate(Vec3 position, TileGen tile);
+    void decorate(Tiles tiles);
 }
diff --git a/core/src/mindustry/maps/planet/TestPlanetGenerator.java b/core/src/mindustry/maps/planet/TestPlanetGenerator.java
index 0e307c107b..9486037dc1 100644
--- a/core/src/mindustry/maps/planet/TestPlanetGenerator.java
+++ b/core/src/mindustry/maps/planet/TestPlanetGenerator.java
@@ -3,11 +3,14 @@ package mindustry.maps.planet;
 import arc.graphics.*;
 import arc.math.*;
 import arc.math.geom.*;
+import arc.struct.*;
 import arc.util.*;
 import arc.util.noise.*;
 import mindustry.content.*;
+import mindustry.game.*;
 import mindustry.world.*;
 
+//TODO refactor into generic planet class
 public class TestPlanetGenerator implements PlanetGenerator{
     Simplex noise = new Simplex();
     float scl = 5f;
@@ -53,6 +56,57 @@ public class TestPlanetGenerator implements PlanetGenerator{
     @Override
     public void generate(Vec3 position, TileGen tile){
         tile.floor = getBlock(position);
+        tile.block = tile.floor.asFloor().wall;
+
+        if(noise.octaveNoise3D(5, 0.6, 8.0, position.x, position.y, position.z) > 0.65){
+            tile.block = Blocks.air;
+        }
+    }
+
+    @Override
+    public void decorate(Tiles tiles){
+        //OvergrowthGenerator generator = new OvergrowthGenerator(tiles.width, tiles.height);
+        //generator.init(Loadouts.basicNucleus);
+        //generator.generate(tiles);
+        GridBits write = new GridBits(tiles.width, tiles.height);
+        GridBits read = new GridBits(tiles.width, tiles.height);
+
+        //double removalChance = 0.2;
+        //remove random tiles
+        //tiles.each((x, y) -> {
+
+        //});
+
+        tiles.each((x, y) -> read.set(x, y, !tiles.get(x, y).block().isAir()));
+
+        int iterations = 4, birthLimit = 16, deathLimit = 16, radius = 3;
+
+        for(int i = 0; i < iterations; i++){
+            tiles.each((x, y) -> {
+                int alive = 0;
+
+                for(int cx = -radius; cx <= radius; cx++){
+                    for(int cy = -radius; cy <= radius; cy++){
+                        if((cx == 0 && cy == 0) || !Mathf.within(cx, cy, radius)) continue;
+                        if(!Structs.inBounds(x + cx, y + cy, tiles.width, tiles.height) || read.get(x + cx, y + cy)){
+                            alive++;
+                        }
+                    }
+                }
+
+                if(read.get(x, y)){
+                    write.set(x, y, alive >= deathLimit);
+                }else{
+                    write.set(x, y, alive > birthLimit);
+                }
+            });
+
+            //flush results.
+            tiles.each((x, y) -> read.set(x, y, write.get(x, y)));
+        }
+
+        tiles.each((x, y) -> tiles.get(x, y).setBlock(!write.get(x, y) ? Blocks.air : tiles.get(x, y).floor().wall));
+        tiles.get(tiles.width /2, tiles.height /2).setBlock(Blocks.coreShard, Team.sharded);
     }
 
     Block getBlock(Vec3 position){
diff --git a/core/src/mindustry/maps/zonegen/DesertWastesGenerator.java b/core/src/mindustry/maps/zonegen/DesertWastesGenerator.java
index a3ee4b6004..201cc6f741 100644
--- a/core/src/mindustry/maps/zonegen/DesertWastesGenerator.java
+++ b/core/src/mindustry/maps/zonegen/DesertWastesGenerator.java
@@ -7,6 +7,7 @@ import mindustry.world.*;
 
 import static mindustry.Vars.schematics;
 
+//TODO remove
 public class DesertWastesGenerator extends BasicGenerator{
 
     public DesertWastesGenerator(int width, int height){
diff --git a/core/src/mindustry/maps/zonegen/OvergrowthGenerator.java b/core/src/mindustry/maps/zonegen/OvergrowthGenerator.java
index d62eeaf076..916449ea5f 100644
--- a/core/src/mindustry/maps/zonegen/OvergrowthGenerator.java
+++ b/core/src/mindustry/maps/zonegen/OvergrowthGenerator.java
@@ -7,6 +7,7 @@ import mindustry.world.*;
 
 import static mindustry.Vars.schematics;
 
+//TODO remove
 public class OvergrowthGenerator extends BasicGenerator{
 
     public OvergrowthGenerator(int width, int height){
@@ -15,13 +16,12 @@ public class OvergrowthGenerator extends BasicGenerator{
 
     @Override
     public void generate(int x, int y){
-        floor = Blocks.moss;
     }
 
     @Override
     public void decorate(Tiles tiles){
         ores(tiles);
-        terrain(tiles, Blocks.sporePine, 70f, 1.4f, 1f);
+        //terrain(tiles, Blocks.sporePine, 70f, 1.4f, 1f);
 
         int rand = 40;
         int border = 25;
@@ -36,7 +36,7 @@ public class OvergrowthGenerator extends BasicGenerator{
         distort(tiles, 20f, 4f);
         inverseFloodFill(tiles, tiles.getn(spawnX, spawnY), Blocks.sporerocks);
 
-        noise(tiles, Blocks.darksandTaintedWater, Blocks.duneRocks, 4, 0.7f, 120f, 0.64f);
+        //noise(tiles, Blocks.darksandTaintedWater, Blocks.duneRocks, 4, 0.7f, 120f, 0.64f);
         //scatter(tiles, Blocks.sporePine, Blocks.whiteTreeDead, 1f);
 
         tiles.getn(endX, endY).setOverlay(Blocks.spawn);
diff --git a/core/src/mindustry/world/Block.java b/core/src/mindustry/world/Block.java
index 79ebe4112d..31ed096ad6 100644
--- a/core/src/mindustry/world/Block.java
+++ b/core/src/mindustry/world/Block.java
@@ -161,6 +161,10 @@ public class Block extends BlockStorage{
         this.solid = false;
     }
 
+    public boolean isAir(){
+        return id == 0;
+    }
+
     public boolean canBreak(Tile tile){
         return true;
     }
diff --git a/core/src/mindustry/world/Tiles.java b/core/src/mindustry/world/Tiles.java
index b751d3d51a..1aac3d0c84 100644
--- a/core/src/mindustry/world/Tiles.java
+++ b/core/src/mindustry/world/Tiles.java
@@ -7,8 +7,9 @@ import java.util.*;
 
 /** A tile container. */
 public class Tiles implements Iterable<Tile>{
+    public final int width, height;
+
     private final Tile[] array;
-    private final int width, height;
     private final TileIterator iterator = new TileIterator();
 
     public Tiles(int width, int height){
@@ -63,14 +64,6 @@ public class Tiles implements Iterable<Tile>{
         return get(Pos.x(pos), Pos.y(pos));
     }
 
-    public int width(){
-        return width;
-    }
-
-    public int height(){
-        return height;
-    }
-
     @Override
     public Iterator<Tile> iterator(){
         iterator.index = 0;
diff --git a/core/src/mindustry/world/blocks/Floor.java b/core/src/mindustry/world/blocks/Floor.java
index fe5fa13e52..b4eca21547 100644
--- a/core/src/mindustry/world/blocks/Floor.java
+++ b/core/src/mindustry/world/blocks/Floor.java
@@ -6,8 +6,8 @@ import arc.graphics.g2d.*;
 import arc.graphics.g2d.TextureAtlas.*;
 import arc.math.*;
 import arc.math.geom.*;
-import arc.util.ArcAnnotate.*;
 import arc.struct.*;
+import arc.util.ArcAnnotate.*;
 import mindustry.content.*;
 import mindustry.entities.*;
 import mindustry.graphics.*;
@@ -16,7 +16,7 @@ import mindustry.type.*;
 import mindustry.ui.*;
 import mindustry.world.*;
 
-import static mindustry.Vars.tilesize;
+import static mindustry.Vars.*;
 
 public class Floor extends Block{
     /** number of different variant regions to use */
@@ -57,6 +57,8 @@ public class Floor extends Block{
     public boolean oreDefault = false;
     /** Ore generation params. */
     public float oreScale = 24f, oreThreshold = 0.828f;
+    /** Wall variant of this block. May be Blocks.air if not found. */
+    public Block wall = Blocks.air;
 
     protected TextureRegion[][] edges;
     protected byte eq = 0;
@@ -92,6 +94,20 @@ public class Floor extends Block{
         edgeRegion = Core.atlas.find("edge");
     }
 
+    @Override
+    public void init(){
+        super.init();
+
+        if(wall == Blocks.air){
+            wall = content.block(name + "Rocks");
+            if(wall == null) wall = content.block(name + "rocks");
+            if(wall == null) wall = content.block(name.replace("darksand", "dune") + "rocks");
+        }
+
+        //keep default value if not found...
+        if(wall == null) wall = Blocks.air;
+    }
+
     @Override
     public void createIcons(MultiPacker packer){
         super.createIcons(packer);
diff --git a/gradle.properties b/gradle.properties
index 60187da317..11145e4c88 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -1,3 +1,3 @@
 org.gradle.daemon=true
 org.gradle.jvmargs=-Xms256m -Xmx1024m
-archash=0b2f044e5955ff700650eebecfb3dfcb629d7a8b
+archash=d20c0312e740a9845a358fc4571926ad784c0bbc
diff --git a/tests/src/test/java/ApplicationTests.java b/tests/src/test/java/ApplicationTests.java
index b190f27b2f..5834390682 100644
--- a/tests/src/test/java/ApplicationTests.java
+++ b/tests/src/test/java/ApplicationTests.java
@@ -388,14 +388,14 @@ public class ApplicationTests{
         Tiles tiles = world.resize(256*2 + 20, 10);
 
         world.beginMapLoad();
-        for(int x = 0; x < tiles.width(); x++){
-            for(int y = 0; y < tiles.height(); y++){
+        for(int x = 0; x < tiles.width; x++){
+            for(int y = 0; y < tiles.height; y++){
                 tiles.set(x, y, new Tile(x, y, Blocks.stone, Blocks.air, Blocks.air));
             }
         }
         int i = 0;
 
-        for(int x = 5; x < tiles.width() && i < content.blocks().size; ){
+        for(int x = 5; x < tiles.width && i < content.blocks().size; ){
             Block block = content.block(i++);
             if(block.isBuildable()){
                 x += block.size;
@@ -405,8 +405,8 @@ public class ApplicationTests{
         }
         world.endMapLoad();
 
-        for(int x = 0; x < tiles.width(); x++){
-            for(int y = 0; y < tiles.height(); y++){
+        for(int x = 0; x < tiles.width; x++){
+            for(int y = 0; y < tiles.height; y++){
                 Tile tile = world.rawTile(x, y);
                 if(tile.entity != null){
                     try{