Slot two is reserved on arty towers.

src/engine/gameManager/BuildingManager.java

@@ -50,6 +50,14 @@ public enum BuildingManager {
         int numOfSlots = _slotLocations.get(building.meshUUID).size();
 
         for (int i = 1; i <= numOfSlots; i++) {
+
+            // Slot two is reserved on Arty towers for the trebuchet
+
+            if (i == 2 &&
+                    building.getBlueprint() != null &&
+                    building.getBlueprint().getBuildingGroup().equals(BuildingGroup.ARTYTOWER))
+                continue;
+
             if (!building.getHirelings().containsValue(i))
                 return i;
         }

src/engine/objects/NPC.java

@@ -356,12 +356,6 @@ public class NPC extends AbstractCharacter {
 			if (slot == -1)
 				Logger.error("No available slot for NPC: " + this.getObjectUUID());
 
-			// Slot one is reserved on Arty towers for the trebuchet
-
-			if (building.getBlueprint() != null &&
-					building.getBlueprint().getBuildingGroup().equals(BuildingGroup.ARTYTOWER))
-				slot = slot + 1;
-
 			building.getHirelings().put(this, slot);
 
 			// Override bind and location for  this npc derived