diff --git a/core/src/mindustry/ai/BlockIndexer.java b/core/src/mindustry/ai/BlockIndexer.java
index ffc8ae6f78..1e55913bc7 100644
--- a/core/src/mindustry/ai/BlockIndexer.java
+++ b/core/src/mindustry/ai/BlockIndexer.java
@@ -115,13 +115,13 @@ public class BlockIndexer{
         if(structQuadrants == null) return;
 
         //go through every tile... ouch
-        for(Tile tile : world.tiles){
+        world.tiles.each(tile -> {
             if(tile.team() == team){
                 int quadrantX = tile.x / quadrantSize;
                 int quadrantY = tile.y / quadrantSize;
                 structQuadrant(team).set(quadrantX, quadrantY);
             }
-        }
+        });
     }
 
     /** @return whether this item is present on this map.*/
diff --git a/core/src/mindustry/content/Blocks.java b/core/src/mindustry/content/Blocks.java
index 126eae5f17..fc0d5bfd87 100644
--- a/core/src/mindustry/content/Blocks.java
+++ b/core/src/mindustry/content/Blocks.java
@@ -19,6 +19,7 @@ import mindustry.world.blocks.defense.*;
 import mindustry.world.blocks.defense.turrets.*;
 import mindustry.world.blocks.distribution.*;
 import mindustry.world.blocks.environment.*;
+import mindustry.world.blocks.legacy.*;
 import mindustry.world.blocks.liquid.*;
 import mindustry.world.blocks.logic.*;
 import mindustry.world.blocks.power.*;
@@ -1863,6 +1864,12 @@ public class Blocks implements ContentList{
             consumes.power(0.05f);
         }};
 
+        //endregion
+        //region legacy
+
+        //looked up by name, no ref needed
+        new LegacyMechPad("legacy-mech-pad");
+
         //endregion
     }
 }
diff --git a/core/src/mindustry/core/World.java b/core/src/mindustry/core/World.java
index 801ee0ae26..8cbc8e958d 100644
--- a/core/src/mindustry/core/World.java
+++ b/core/src/mindustry/core/World.java
@@ -19,6 +19,7 @@ import mindustry.maps.filters.*;
 import mindustry.maps.filters.GenerateFilter.*;
 import mindustry.type.*;
 import mindustry.world.*;
+import mindustry.world.blocks.legacy.*;
 
 import static mindustry.Vars.*;
 
@@ -172,6 +173,12 @@ public class World{
         prepareTiles(tiles);
 
         for(Tile tile : tiles){
+            //remove legacy blocks; they need to stop existing
+            if(tile.block() instanceof LegacyBlock){
+                tile.remove();
+                continue;
+            }
+
             tile.updateOcclusion();
 
             if(tile.entity != null){
@@ -447,8 +454,8 @@ public class World{
 
     private class Context implements WorldContext{
         @Override
-        public Tile tile(int x, int y){
-            return tiles.get(x, y);
+        public Tile tile(int index){
+            return tiles.geti(index);
         }
 
         @Override
diff --git a/core/src/mindustry/editor/MapEditor.java b/core/src/mindustry/editor/MapEditor.java
index 7ffea22491..3d82eca733 100644
--- a/core/src/mindustry/editor/MapEditor.java
+++ b/core/src/mindustry/editor/MapEditor.java
@@ -292,8 +292,8 @@ public class MapEditor{
 
     class Context implements WorldContext{
         @Override
-        public Tile tile(int x, int y){
-            return world.tile(x, y);
+        public Tile tile(int index){
+            return world.tiles.geti(index);
         }
 
         @Override
diff --git a/core/src/mindustry/entities/def/UnitComp.java b/core/src/mindustry/entities/def/UnitComp.java
index 5b3cbfaa06..05e2840cb7 100644
--- a/core/src/mindustry/entities/def/UnitComp.java
+++ b/core/src/mindustry/entities/def/UnitComp.java
@@ -126,7 +126,7 @@ abstract class UnitComp implements Healthc, Velc, Statusc, Teamc, Itemsc, Hitbox
 
         if(tile != null){
             //unit block update
-            if(tile.entity != null){
+            if(tile.entity != null && isGrounded()){
                 tile.entity.unitOn(this);
             }
 
diff --git a/core/src/mindustry/io/MapIO.java b/core/src/mindustry/io/MapIO.java
index 20657b5186..2ecde02242 100644
--- a/core/src/mindustry/io/MapIO.java
+++ b/core/src/mindustry/io/MapIO.java
@@ -104,9 +104,9 @@ public class MapIO{
                 @Override public void end(){}
 
                 @Override
-                public Tile tile(int x, int y){
-                    tile.x = (short)x;
-                    tile.y = (short)y;
+                public Tile tile(int index){
+                    tile.x = (short)(index % map.width);
+                    tile.y = (short)(index / map.width);
                     return tile;
                 }
 
diff --git a/core/src/mindustry/io/SaveFileReader.java b/core/src/mindustry/io/SaveFileReader.java
index a06ff4bf56..4f18ef56c4 100644
--- a/core/src/mindustry/io/SaveFileReader.java
+++ b/core/src/mindustry/io/SaveFileReader.java
@@ -13,7 +13,15 @@ public abstract class SaveFileReader{
     protected final ReusableByteOutStream byteOutputSmall = new ReusableByteOutStream();
     protected final DataOutputStream dataBytesSmall = new DataOutputStream(byteOutputSmall);
     protected final ObjectMap<String, String> fallback = ObjectMap.of(
-        "dart-mech-pad", "dart-ship-pad"
+    "dart-mech-pad", "legacy-mech-pad",
+    "dart-ship-pad", "legacy-mech-pad",
+    "javelin-ship-pad", "legacy-mech-pad",
+    "trident-ship-pad", "legacy-mech-pad",
+    "glaive-ship-pad", "legacy-mech-pad",
+    "alpha-mech-pad", "legacy-mech-pad",
+    "tau-mech-pad", "legacy-mech-pad",
+    "omega-mech-pad", "legacy-mech-pad",
+    "delta-mech-pad", "legacy-mech-pad"
     );
 
     protected void region(String name, DataInput stream, CounterInputStream counter, IORunner<DataInput> cons) throws IOException{
diff --git a/core/src/mindustry/io/SaveVersion.java b/core/src/mindustry/io/SaveVersion.java
index 9041b5722e..be1c04175e 100644
--- a/core/src/mindustry/io/SaveVersion.java
+++ b/core/src/mindustry/io/SaveVersion.java
@@ -186,7 +186,7 @@ public abstract class SaveVersion extends SaveFileReader{
             for(int i = 0; i < width * height; i++){
                 int x = i % width, y = i / width;
                 Block block = content.block(stream.readShort());
-                Tile tile = context.tile(x, y);
+                Tile tile = context.tile(i);
                 if(block == null) block = Blocks.air;
                 boolean isCenter = true;
 
@@ -214,8 +214,7 @@ public abstract class SaveVersion extends SaveFileReader{
                     int consecutives = stream.readUnsignedByte();
 
                     for(int j = i + 1; j < i + 1 + consecutives; j++){
-                        int newx = j % width, newy = j / width;
-                        context.tile(newx, newy).setBlock(block);
+                        context.tile(j).setBlock(block);
                     }
 
                     i += consecutives;
diff --git a/core/src/mindustry/io/legacy/LegacySaveVersion.java b/core/src/mindustry/io/legacy/LegacySaveVersion.java
index fb99262b00..47f7e26955 100644
--- a/core/src/mindustry/io/legacy/LegacySaveVersion.java
+++ b/core/src/mindustry/io/legacy/LegacySaveVersion.java
@@ -49,13 +49,12 @@ public abstract class LegacySaveVersion extends SaveVersion{
 
             //read blocks
             for(int i = 0; i < width * height; i++){
-                int x = i % width, y = i / width;
                 Block block = content.block(stream.readShort());
-                Tile tile = context.tile(x, y);
+                Tile tile = context.tile(i);
                 if(block == null) block = Blocks.air;
 
                 //occupied by multiblock part
-                boolean occupied = tile.entity != null && !tile.isCenter();
+                boolean occupied = tile.entity != null && !tile.isCenter() && (tile.entity.block() == block || block == Blocks.air);
 
                 //do not override occupied cells
                 if(!occupied){
@@ -92,8 +91,7 @@ public abstract class LegacySaveVersion extends SaveVersion{
                     //air is a waste of time and may mess up multiblocks
                     if(block != Blocks.air){
                         for(int j = i + 1; j < i + 1 + consecutives; j++){
-                            int newx = j % width, newy = j / width;
-                            context.tile(newx, newy).setBlock(block);
+                            context.tile(j).setBlock(block);
                         }
                     }
 
diff --git a/core/src/mindustry/io/legacy/Save3.java b/core/src/mindustry/io/legacy/Save3.java
index b69312071e..3924c18b3d 100644
--- a/core/src/mindustry/io/legacy/Save3.java
+++ b/core/src/mindustry/io/legacy/Save3.java
@@ -8,6 +8,7 @@ import java.io.*;
 import static mindustry.Vars.content;
 
 public class Save3 extends LegacySaveVersion{
+
     public Save3(){
         super(3);
     }
diff --git a/core/src/mindustry/world/Tile.java b/core/src/mindustry/world/Tile.java
index 9be20635d6..ba2bfeda20 100644
--- a/core/src/mindustry/world/Tile.java
+++ b/core/src/mindustry/world/Tile.java
@@ -173,6 +173,8 @@ public class Tile implements Position{
         if(block.isMultiblock()){
             int offsetx = -(block.size - 1) / 2;
             int offsety = -(block.size - 1) / 2;
+            Tilec entity = this.entity;
+            Block block = this.block;
 
             //two passes: first one clears, second one sets
             for(int pass = 0; pass < 2; pass++){
@@ -198,6 +200,9 @@ public class Tile implements Position{
                     }
                 }
             }
+
+            this.entity = entity;
+            this.block = block;
         }
     }
 
diff --git a/core/src/mindustry/world/Tiles.java b/core/src/mindustry/world/Tiles.java
index 000cf7efee..21177ed0ff 100644
--- a/core/src/mindustry/world/Tiles.java
+++ b/core/src/mindustry/world/Tiles.java
@@ -65,8 +65,18 @@ public class Tiles implements Iterable<Tile>{
         return get(Point2.x(pos), Point2.y(pos));
     }
 
+    public void each(Cons<Tile> cons){
+        for(Tile tile : array){
+            cons.get(tile);
+        }
+    }
+
     @Override
     public Iterator<Tile> iterator(){
+        if(iterator.index != 0 && iterator.index != array.length){
+            iterator.index = 0;
+            throw new IllegalArgumentException("Double iteration. " + iterator.index + " != " + array.length);
+        }
         iterator.index = 0;
         return iterator;
     }
diff --git a/core/src/mindustry/world/WorldContext.java b/core/src/mindustry/world/WorldContext.java
index 03a6cccea7..760aa0938f 100644
--- a/core/src/mindustry/world/WorldContext.java
+++ b/core/src/mindustry/world/WorldContext.java
@@ -3,7 +3,7 @@ package mindustry.world;
 public interface WorldContext{
 
     /** Return a tile in the tile array.*/
-    Tile tile(int x, int y);
+    Tile tile(int index);
 
     /** Create the tile array.*/
     void resize(int width, int height);
diff --git a/core/src/mindustry/world/blocks/distribution/Conveyor.java b/core/src/mindustry/world/blocks/distribution/Conveyor.java
index cdf4f6a751..8744f08c37 100644
--- a/core/src/mindustry/world/blocks/distribution/Conveyor.java
+++ b/core/src/mindustry/world/blocks/distribution/Conveyor.java
@@ -118,11 +118,15 @@ public class Conveyor extends Block implements Autotiler{
 
         int blendbits;
         int blendsclx, blendscly;
+        boolean everupdated = false;
 
         float clogHeat = 0f;
 
         @Override
         public void draw(){
+            if(!everupdated){
+                Log.info("--DID NOT UPDATE {0}", tile);
+            }
             byte rotation = tile.rotation();
             int frame = clogHeat <= 0.5f ? (int)(((Time.time() * speed * 8f * timeScale())) % 4) : 0;
             Draw.rect(regions[Mathf.clamp(blendbits, 0, regions.length - 1)][Mathf.clamp(frame, 0, regions[0].length - 1)], x, y,
@@ -142,6 +146,7 @@ public class Conveyor extends Block implements Autotiler{
             blendbits = bits[0];
             blendsclx = bits[1];
             blendscly = bits[2];
+            everupdated = true;
 
             if(tile.front() != null && tile.front() != null){
                 next = tile.front();
diff --git a/core/src/mindustry/world/blocks/legacy/LegacyBlock.java b/core/src/mindustry/world/blocks/legacy/LegacyBlock.java
new file mode 100644
index 0000000000..0401387022
--- /dev/null
+++ b/core/src/mindustry/world/blocks/legacy/LegacyBlock.java
@@ -0,0 +1,11 @@
+package mindustry.world.blocks.legacy;
+
+import mindustry.world.*;
+
+/** Any subclass of this will be removed upon world load. */
+public class LegacyBlock extends Block{
+
+    public LegacyBlock(String name){
+        super(name);
+    }
+}
diff --git a/core/src/mindustry/world/blocks/legacy/LegacyMechPad.java b/core/src/mindustry/world/blocks/legacy/LegacyMechPad.java
new file mode 100644
index 0000000000..f7bdceb25e
--- /dev/null
+++ b/core/src/mindustry/world/blocks/legacy/LegacyMechPad.java
@@ -0,0 +1,25 @@
+package mindustry.world.blocks.legacy;
+
+import arc.util.io.*;
+import mindustry.gen.*;
+import mindustry.world.*;
+
+public class LegacyMechPad extends Block{
+
+    public LegacyMechPad(String name){
+        super(name);
+        update = true;
+    }
+
+    public class LegacyMechPadEntity extends TileEntity{
+
+        @Override
+        public void read(Reads read, byte revision){
+            super.read(read, revision);
+            //read 3 floats for pad data, and discard them
+            read.f();
+            read.f();
+            read.f();
+        }
+    }
+}
diff --git a/core/src/mindustry/world/blocks/production/Drill.java b/core/src/mindustry/world/blocks/production/Drill.java
index e43b10be03..805743d2a8 100644
--- a/core/src/mindustry/world/blocks/production/Drill.java
+++ b/core/src/mindustry/world/blocks/production/Drill.java
@@ -204,7 +204,7 @@ public class Drill extends Block{
         float progress;
         int index;
         float warmup;
-        float drillTime;
+        float timeDrilled;
         float lastDrillSpeed;
 
         int dominantItems;
@@ -249,7 +249,7 @@ public class Drill extends Block{
                 dump(dominantItem);
             }
 
-            drillTime += warmup * delta();
+            timeDrilled += warmup * delta();
 
             if(items.total() < itemCapacity && dominantItems > 0 && consValid()){
 
@@ -263,8 +263,7 @@ public class Drill extends Block{
 
                 lastDrillSpeed = (speed * dominantItems * warmup) / (drillTime + hardnessDrillMultiplier * dominantItem.hardness);
                 warmup = Mathf.lerpDelta(warmup, speed, warmupSpeed);
-                progress += delta()
-                * dominantItems * speed * warmup;
+                progress += delta() * dominantItems * speed * warmup;
 
                 if(Mathf.chance(Time.delta() * updateEffectChance * warmup))
                     updateEffect.at(getX() + Mathf.range(size * 2f), getY() + Mathf.range(size * 2f));
@@ -305,7 +304,7 @@ public class Drill extends Block{
                 Draw.color();
             }
 
-            Draw.rect(rotatorRegion, x, y, drillTime * rotateSpeed);
+            Draw.rect(rotatorRegion, x, y, timeDrilled * rotateSpeed);
 
             Draw.rect(topRegion, x, y);
 
diff --git a/gradle.properties b/gradle.properties
index 1bbf7facaa..98f6e2b676 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -1,3 +1,3 @@
 org.gradle.daemon=true
 org.gradle.jvmargs=-Xms256m -Xmx1024m
-archash=3c2fae9b66b6affc1ba6701cce19ca9625c5e1b1
+archash=3a72937157113d8a5cd44bcc0b296c50e316c941
diff --git a/server/build.gradle b/server/build.gradle
index ad1b49bf7b..1da9b0c7ee 100644
--- a/server/build.gradle
+++ b/server/build.gradle
@@ -36,7 +36,7 @@ task debug(dependsOn: classes, type: JavaExec){
 task dist(type: Jar){
     from files(sourceSets.main.output.classesDirs)
     from files(sourceSets.main.output.resourcesDir)
-    from{ configurations.compile.collect{ zipTree(it) } }
+    from {configurations.compile.collect{ it.isDirectory() ? it : zipTree(it) }}
     from files(project.assetsDir)
     exclude("sprites/**")
     exclude("music/**")