diff --git a/Plugin Cubot/src/main/java/net/simon987/cubotplugin/Cubot.java b/Plugin Cubot/src/main/java/net/simon987/cubotplugin/Cubot.java
index e153c9e..f70433c 100644
--- a/Plugin Cubot/src/main/java/net/simon987/cubotplugin/Cubot.java	
+++ b/Plugin Cubot/src/main/java/net/simon987/cubotplugin/Cubot.java	
@@ -77,8 +77,8 @@ public class Cubot extends GameObject implements Updatable, ControllableUnit {
     @Override
     public JSONObject serialise() {
         JSONObject json = new JSONObject();
-        json.put("id", getObjectId());
-        json.put("type", ID);
+        json.put("i", getObjectId());
+        json.put("t", ID);
         json.put("x", getX());
         json.put("y", getY());
         json.put("direction", getDirection().ordinal());
@@ -98,7 +98,7 @@ public class Cubot extends GameObject implements Updatable, ControllableUnit {
     public static Cubot deserialize(JSONObject json) {
 
         Cubot cubot = new Cubot();
-        cubot.setObjectId((int) (long) json.get("id"));
+        cubot.setObjectId((int) (long) json.get("i"));
         cubot.setX((int) (long) json.get("x"));
         cubot.setY((int) (long) json.get("y"));
         cubot.hp = (int) (long) json.get("hp");
diff --git a/Plugin Cubot/src/main/java/net/simon987/cubotplugin/CubotPlugin.java b/Plugin Cubot/src/main/java/net/simon987/cubotplugin/CubotPlugin.java
index 716974d..8060d11 100644
--- a/Plugin Cubot/src/main/java/net/simon987/cubotplugin/CubotPlugin.java	
+++ b/Plugin Cubot/src/main/java/net/simon987/cubotplugin/CubotPlugin.java	
@@ -25,7 +25,7 @@ public class CubotPlugin extends ServerPlugin implements GameObjectDeserializer,
     @Override
     public GameObject deserializeObject(JSONObject object) {
 
-        int objType = (int) (long) object.get("type");
+        int objType = (int) (long) object.get("t");
 
         if (objType == Cubot.ID) {
 
diff --git a/Plugin Cubot/src/main/java/net/simon987/cubotplugin/event/UserCreationListener.java b/Plugin Cubot/src/main/java/net/simon987/cubotplugin/event/UserCreationListener.java
index 64f2030..bcfc13d 100644
--- a/Plugin Cubot/src/main/java/net/simon987/cubotplugin/event/UserCreationListener.java	
+++ b/Plugin Cubot/src/main/java/net/simon987/cubotplugin/event/UserCreationListener.java	
@@ -29,6 +29,7 @@ public class UserCreationListener implements GameEventListener {
                 GameServer.INSTANCE.getConfig().getInt("new_user_worldX"),
                 GameServer.INSTANCE.getConfig().getInt("new_user_worldY")));
         cubot.getWorld().getGameObjects().add(cubot);
+        cubot.getWorld().incUpdatable();
 
         cubot.setObjectId(GameServer.INSTANCE.getGameUniverse().getNextObjectId());
 
diff --git a/Plugin NPC/src/main/java/net/simon987/npcplugin/HarvestTask.java b/Plugin NPC/src/main/java/net/simon987/npcplugin/HarvestTask.java
index 72703e5..a5f5ef8 100644
--- a/Plugin NPC/src/main/java/net/simon987/npcplugin/HarvestTask.java	
+++ b/Plugin NPC/src/main/java/net/simon987/npcplugin/HarvestTask.java	
@@ -1,6 +1,7 @@
 package net.simon987.npcplugin;
 
 
+import net.simon987.server.GameServer;
 import net.simon987.server.assembly.Util;
 import net.simon987.server.game.Direction;
 import net.simon987.server.game.GameObject;
@@ -83,7 +84,18 @@ public class HarvestTask extends NPCTask {
             } else {
 
                 if (nextWorldDirection == null) {
-                    nextWorldDirection = Direction.getDirection(random.nextInt(3));
+
+                    //Stay near the center of the map 50% of the time
+                    if (random.nextBoolean()) {
+
+                        nextWorldDirection = Direction.getDirectionTo(npc.getX(), npc.getY(),
+                                GameServer.INSTANCE.getConfig().getInt("new_user_worldX"),
+                                GameServer.INSTANCE.getConfig().getInt("new_user_worldY"));
+
+                    } else {
+                        nextWorldDirection = Direction.getDirection(random.nextInt(3));
+                    }
+
                     pause += 6;
                 }
                 npc.gotoWorld(nextWorldDirection);
diff --git a/Plugin NPC/src/main/java/net/simon987/npcplugin/HarvesterNPC.java b/Plugin NPC/src/main/java/net/simon987/npcplugin/HarvesterNPC.java
index a360485..9d6e7cb 100644
--- a/Plugin NPC/src/main/java/net/simon987/npcplugin/HarvesterNPC.java	
+++ b/Plugin NPC/src/main/java/net/simon987/npcplugin/HarvesterNPC.java	
@@ -37,14 +37,14 @@ public class HarvesterNPC extends NonPlayerCharacter {
     public JSONObject serialise() {
         JSONObject json = super.serialise();
 
-        json.put("id", getObjectId());
+        json.put("i", getObjectId());
         json.put("x", getX());
         json.put("y", getY());
         json.put("direction", getDirection().ordinal());
         json.put("hp", hp);
         json.put("energy", energy);
         json.put("action", getAction().ordinal());
-        json.put("type", 10);
+        json.put("t", 10);
 
         return json;
     }
@@ -52,7 +52,7 @@ public class HarvesterNPC extends NonPlayerCharacter {
     public static HarvesterNPC deserialize(JSONObject json) {
 
         HarvesterNPC npc = new HarvesterNPC();
-        npc.setObjectId((int) (long) json.get("id"));
+        npc.setObjectId((int) (long) json.get("i"));
         npc.setX((int) (long) json.get("x"));
         npc.setY((int) (long) json.get("y"));
         npc.hp = (int) (long) json.get("hp");
diff --git a/Plugin NPC/src/main/java/net/simon987/npcplugin/NonPlayerCharacter.java b/Plugin NPC/src/main/java/net/simon987/npcplugin/NonPlayerCharacter.java
index 5ca540c..1cd5f64 100644
--- a/Plugin NPC/src/main/java/net/simon987/npcplugin/NonPlayerCharacter.java	
+++ b/Plugin NPC/src/main/java/net/simon987/npcplugin/NonPlayerCharacter.java	
@@ -57,8 +57,6 @@ public abstract class NonPlayerCharacter extends GameObject implements Updatable
 
     public boolean gotoWorld(Direction direction) {
 
-        System.out.println("going " + direction);
-
         if (direction == Direction.NORTH) {
             if (!moveTo(8, 0, 0)) {
                 setDirection(Direction.NORTH);
diff --git a/Plugin NPC/src/main/java/net/simon987/npcplugin/NpcPlugin.java b/Plugin NPC/src/main/java/net/simon987/npcplugin/NpcPlugin.java
index 331c64a..ceb8311 100644
--- a/Plugin NPC/src/main/java/net/simon987/npcplugin/NpcPlugin.java	
+++ b/Plugin NPC/src/main/java/net/simon987/npcplugin/NpcPlugin.java	
@@ -22,7 +22,7 @@ public class NpcPlugin extends ServerPlugin implements GameObjectDeserializer {
     @Override
     public GameObject deserializeObject(JSONObject object) {
 
-        int objType = (int) (long) object.get("type");
+        int objType = (int) (long) object.get("t");
 
         if (objType == HarvesterNPC.ID) {
             return HarvesterNPC.deserialize(object);
diff --git a/Plugin NPC/src/main/java/net/simon987/npcplugin/event/WorldUpdateListener.java b/Plugin NPC/src/main/java/net/simon987/npcplugin/event/WorldUpdateListener.java
index e507d28..2a4b43c 100644
--- a/Plugin NPC/src/main/java/net/simon987/npcplugin/event/WorldUpdateListener.java	
+++ b/Plugin NPC/src/main/java/net/simon987/npcplugin/event/WorldUpdateListener.java	
@@ -43,9 +43,8 @@ public class WorldUpdateListener implements GameEventListener {
                     npc.setX(p.x);
                     npc.setY(p.y);
                     world.getGameObjects().add(npc);
+                    world.incUpdatable();
                 }
-
-
             }
 
 
diff --git a/Plugin Plant/src/main/java/net/simon987/biomassplugin/BiomassBlob.java b/Plugin Plant/src/main/java/net/simon987/biomassplugin/BiomassBlob.java
index 69d1727..80fa1b4 100644
--- a/Plugin Plant/src/main/java/net/simon987/biomassplugin/BiomassBlob.java	
+++ b/Plugin Plant/src/main/java/net/simon987/biomassplugin/BiomassBlob.java	
@@ -16,7 +16,7 @@ public class BiomassBlob extends GameObject implements InventoryHolder {
     /**
      * Style of the blob (Only visual)
      */
-    private int style;
+    //  private int style;
 
     private static final int ITM_BIOMASS = 1;
 
@@ -30,12 +30,12 @@ public class BiomassBlob extends GameObject implements InventoryHolder {
 
         JSONObject json = new JSONObject();
 
-        json.put("type", ID);
-        json.put("id", getObjectId());
+        json.put("t", ID);
+        json.put("i", getObjectId());
         json.put("x", getX());
         json.put("y", getY());
-        json.put("biomassCount", biomassCount);
-        json.put("style", style);
+        json.put("b", biomassCount);
+        //  json.put("style", style);
 
         return json;
     }
@@ -49,23 +49,23 @@ public class BiomassBlob extends GameObject implements InventoryHolder {
         this.biomassCount = biomassCount;
     }
 
-    public int getStyle() {
-        return style;
-    }
-
-    public void setStyle(int style) {
-        this.style = style;
-    }
+//    public int getStyle() {
+//        return style;
+//    }
+//
+//    public void setStyle(int style) {
+//        this.style = style;
+//    }
 
     public static BiomassBlob deserialize(JSONObject json) {
 
         BiomassBlob biomassBlob = new BiomassBlob();
 
-        biomassBlob.setObjectId((int) (long) json.get("id"));
+        biomassBlob.setObjectId((int) (long) json.get("i"));
         biomassBlob.setX((int) (long) json.get("x"));
         biomassBlob.setY((int) (long) json.get("y"));
-        biomassBlob.style = (int) (long) json.get("style");
-        biomassBlob.biomassCount = (int) (long) json.get("biomassCount");
+        //   biomassBlob.style = (int) (long) json.get("style");
+        biomassBlob.biomassCount = (int) (long) json.get("b");
 
         return biomassBlob;
     }
diff --git a/Plugin Plant/src/main/java/net/simon987/biomassplugin/BiomassPlugin.java b/Plugin Plant/src/main/java/net/simon987/biomassplugin/BiomassPlugin.java
index 08295fa..a19fbd0 100644
--- a/Plugin Plant/src/main/java/net/simon987/biomassplugin/BiomassPlugin.java	
+++ b/Plugin Plant/src/main/java/net/simon987/biomassplugin/BiomassPlugin.java	
@@ -23,7 +23,7 @@ public class BiomassPlugin extends ServerPlugin implements GameObjectDeserialize
     @Override
     public GameObject deserializeObject(JSONObject object) {
 
-        int objType = (int) (long) object.get("type");
+        int objType = (int) (long) object.get("t");
 
         if (objType == BiomassBlob.ID) {
 
diff --git a/Plugin Plant/src/main/java/net/simon987/biomassplugin/WorldUtils.java b/Plugin Plant/src/main/java/net/simon987/biomassplugin/WorldUtils.java
index 1901ba1..f0217f9 100644
--- a/Plugin Plant/src/main/java/net/simon987/biomassplugin/WorldUtils.java	
+++ b/Plugin Plant/src/main/java/net/simon987/biomassplugin/WorldUtils.java	
@@ -65,7 +65,7 @@ public class WorldUtils {
 
                 BiomassBlob biomassBlob = new BiomassBlob();
                 biomassBlob.setObjectId(GameServer.INSTANCE.getGameUniverse().getNextObjectId());
-                biomassBlob.setStyle(0); //TODO: set style depending on difficulty level? or random? from config?
+                // biomassBlob.setStyle(0); //TODO: set style depending on difficulty level? or random? from config?
                 biomassBlob.setBiomassCount(yield);
                 biomassBlob.setX(p.x);
                 biomassBlob.setY(p.y);
diff --git a/Server/src/main/java/net/simon987/server/GameServer.java b/Server/src/main/java/net/simon987/server/GameServer.java
index 714c906..b0237bf 100644
--- a/Server/src/main/java/net/simon987/server/GameServer.java
+++ b/Server/src/main/java/net/simon987/server/GameServer.java
@@ -147,8 +147,12 @@ public class GameServer implements Runnable {
         //Process each worlds
         //Avoid concurrent modification
         ArrayList<World> worlds = new ArrayList<>(gameUniverse.getWorlds());
+        int updatedWorlds = 0;
         for (World world : worlds) {
-            world.update();
+            if (world.shouldUpdate()) {
+                world.update();
+                updatedWorlds++;
+            }
         }
 
         //Save
@@ -163,7 +167,8 @@ public class GameServer implements Runnable {
 
         socketServer.tick();
 
-        LogManager.LOGGER.info("Processed " + gameUniverse.getWorlds().size() + " worlds");
+        LogManager.LOGGER.info("Processed " + gameUniverse.getWorlds().size() + " worlds (" + updatedWorlds +
+                ") updated");
     }
 
     /**
diff --git a/Server/src/main/java/net/simon987/server/Main.java b/Server/src/main/java/net/simon987/server/Main.java
index 5875215..02542be 100644
--- a/Server/src/main/java/net/simon987/server/Main.java
+++ b/Server/src/main/java/net/simon987/server/Main.java
@@ -17,6 +17,7 @@ public class Main {
         //Load
         GameServer.INSTANCE.getGameUniverse().load(new File("save.json"));
 
+
         SocketServer socketServer = new SocketServer(new InetSocketAddress(config.getString("webSocket_host"),
                 config.getInt("webSocket_port")), config);
 
diff --git a/Server/src/main/java/net/simon987/server/game/Direction.java b/Server/src/main/java/net/simon987/server/game/Direction.java
index 1c0da0f..0d0349a 100755
--- a/Server/src/main/java/net/simon987/server/game/Direction.java
+++ b/Server/src/main/java/net/simon987/server/game/Direction.java
@@ -58,4 +58,26 @@ public enum Direction {
         }
 
     }
+
+    /**
+     * Get direction to move from (x1, y1) to (x2, y2)
+     */
+    public static Direction getDirectionTo(int x1, int y1, int x2, int y2) {
+
+        int dx = x2 - x1;
+        int dy = y2 - y1;
+
+        if (dx > 0 && dx >= dy) {
+            return Direction.EAST;
+        } else if (dx < 0 && dx <= dy) {
+            return Direction.WEST;
+        } else if (dy > 0 && dy >= dx) {
+            return Direction.NORTH;
+        } else if (dy < 0 && dy <= dx) {
+            return Direction.SOUTH;
+        } else {
+            return null;
+        }
+
+    }
 }
diff --git a/Server/src/main/java/net/simon987/server/game/GameObject.java b/Server/src/main/java/net/simon987/server/game/GameObject.java
index 09fc8b1..c64bcd1 100755
--- a/Server/src/main/java/net/simon987/server/game/GameObject.java
+++ b/Server/src/main/java/net/simon987/server/game/GameObject.java
@@ -82,7 +82,9 @@ public abstract class GameObject implements JSONSerialisable {
 
             if (leftWorld != null) {
                 world.getGameObjects().remove(this);
+                world.decUpdatable();
                 leftWorld.getGameObjects().add(this);
+                leftWorld.incUpdatable();
                 setWorld(leftWorld);
 
                 x = World.WORLD_SIZE - 1;
@@ -99,7 +101,9 @@ public abstract class GameObject implements JSONSerialisable {
 
             if (rightWorld != null) {
                 world.getGameObjects().remove(this);
+                world.decUpdatable();
                 rightWorld.getGameObjects().add(this);
+                rightWorld.incUpdatable();
                 setWorld(rightWorld);
 
                 x = 0;
@@ -117,7 +121,9 @@ public abstract class GameObject implements JSONSerialisable {
 
             if (upWorld != null) {
                 world.getGameObjects().remove(this);
+                world.decUpdatable();
                 upWorld.getGameObjects().add(this);
+                upWorld.incUpdatable();
                 setWorld(upWorld);
 
                 y = World.WORLD_SIZE - 1;
@@ -135,7 +141,9 @@ public abstract class GameObject implements JSONSerialisable {
 
             if (downWorld != null) {
                 world.getGameObjects().remove(this);
+                world.decUpdatable();
                 downWorld.getGameObjects().add(this);
+                downWorld.incUpdatable();
                 setWorld(downWorld);
 
                 y = 0;
diff --git a/Server/src/main/java/net/simon987/server/game/World.java b/Server/src/main/java/net/simon987/server/game/World.java
index dfea379..60b939a 100644
--- a/Server/src/main/java/net/simon987/server/game/World.java
+++ b/Server/src/main/java/net/simon987/server/game/World.java
@@ -30,6 +30,11 @@ public class World implements JSONSerialisable {
 
     private ArrayList<GameObject> gameObjects = new ArrayList<>(16);
 
+    /**
+     * If this number is greater than 0, the World will be updated.
+     */
+    private int updatable = 0;
+
     public World(int x, int y, TileMap tileMap) {
         this.x = x;
         this.y = y;
@@ -114,13 +119,15 @@ public class World implements JSONSerialisable {
         for (GameObject obj : gameObjects_) {
             objects.add(obj.serialise());
         }
-        json.put("objects", objects);
+        json.put("o", objects);
 
-        json.put("terrain", tileMap.serialise());
+        json.put("t", tileMap.serialise());
 
         json.put("x", x);
         json.put("y", y);
 
+        json.put("u", updatable);
+
         return json;
     }
 
@@ -145,10 +152,11 @@ public class World implements JSONSerialisable {
         World world = new World();
         world.x = (int) (long) json.get("x");
         world.y = (int) (long) json.get("y");
+        world.updatable = (int) (long) json.get("u");
 
-        world.tileMap = TileMap.deserialize((JSONObject) json.get("terrain"));
+        world.tileMap = TileMap.deserialize((JSONObject) json.get("t"));
 
-        for (JSONObject objJson : (ArrayList<JSONObject>) json.get("objects")) {
+        for (JSONObject objJson : (ArrayList<JSONObject>) json.get("o")) {
 
             GameObject object = GameObject.deserialize(objJson);
 
@@ -258,4 +266,15 @@ public class World implements JSONSerialisable {
         return gameObjects;
     }
 
+    public void incUpdatable() {
+        updatable++;
+    }
+
+    public void decUpdatable() {
+        updatable--;
+    }
+
+    public boolean shouldUpdate() {
+        return updatable > 0;
+    }
 }
diff --git a/config.properties b/config.properties
index 56d4be3..dca7da3 100644
--- a/config.properties
+++ b/config.properties
@@ -17,7 +17,7 @@ cert_path=certificates
 # ----------------------------------------------
 
 # Length of a tick in ms
-tick_length=250
+tick_length=125
 # Default offset of the origin (starting point of code execution) in words
 org_offset=512
 # Address of the stack bottom
diff --git a/plugins/Cubot.jar b/plugins/Cubot.jar
index 3c676ff..a030401 100644
Binary files a/plugins/Cubot.jar and b/plugins/Cubot.jar differ
diff --git a/plugins/Plant.jar b/plugins/Plant.jar
index 35a0817..238f938 100644
Binary files a/plugins/Plant.jar and b/plugins/Plant.jar differ
diff --git a/plugins/Plugin NPC.jar b/plugins/Plugin NPC.jar
index eee586f..67072c8 100644
Binary files a/plugins/Plugin NPC.jar and b/plugins/Plugin NPC.jar differ