diff --git a/core/src/mindustry/Vars.java b/core/src/mindustry/Vars.java
index d0995ca3a8..8269c05b06 100644
--- a/core/src/mindustry/Vars.java
+++ b/core/src/mindustry/Vars.java
@@ -56,7 +56,7 @@ public class Vars implements Loadable{
     /** URL for sending crash reports to */
     public static final String crashReportURL = "http://192.99.169.18/report";
     /** URL the links to the wiki's modding guide.*/
-    public static final String modGuideURL = "https://mindustrygame.github.io/wiki/modding/";
+    public static final String modGuideURL = "https://mindustrygame.github.io/wiki/modding/1-modding/";
     /** URL to the JSON file containing all the global, public servers. Not queried in BE. */
     public static final String serverJsonURL = "https://raw.githubusercontent.com/Anuken/Mindustry/master/servers.json";
     /** URL to the JSON file containing all the BE servers. Only queried in BE. */
diff --git a/core/src/mindustry/mod/ContentParser.java b/core/src/mindustry/mod/ContentParser.java
index 4cd9d704f5..e95639ed2e 100644
--- a/core/src/mindustry/mod/ContentParser.java
+++ b/core/src/mindustry/mod/ContentParser.java
@@ -309,6 +309,10 @@ public class ContentParser{
 
                 }
 
+                if(value.has("controller")){
+                    unit.defaultController = make(resolve(value.getString("controller"), "mindustry.ai.type"));
+                }
+
                 //read extra default waves
                 if(value.has("waves")){
                     JsonValue waves = value.remove("waves");
diff --git a/core/src/mindustry/world/blocks/environment/OverlayFloor.java b/core/src/mindustry/world/blocks/environment/OverlayFloor.java
index 4c57943aed..c20eccceaf 100644
--- a/core/src/mindustry/world/blocks/environment/OverlayFloor.java
+++ b/core/src/mindustry/world/blocks/environment/OverlayFloor.java
@@ -4,7 +4,7 @@ import arc.graphics.g2d.*;
 import arc.math.*;
 import mindustry.world.*;
 
-/**A type of floor that is overlaid on top of over floors.*/
+/**A type of floor that is overlaid on top of other floors.*/
 public class OverlayFloor extends Floor{
 
     public OverlayFloor(String name){
diff --git a/core/src/mindustry/world/blocks/units/ControlCenter.java b/core/src/mindustry/world/blocks/units/ControlCenter.java
deleted file mode 100644
index ab99470b93..0000000000
--- a/core/src/mindustry/world/blocks/units/ControlCenter.java
+++ /dev/null
@@ -1,16 +0,0 @@
-package mindustry.world.blocks.units;
-
-import mindustry.gen.*;
-import mindustry.world.*;
-
-public class ControlCenter extends Block{
-
-    public ControlCenter(String name){
-        super(name);
-        update = true;
-    }
-
-    public class ControlCenterBuild extends Building{
-
-    }
-}