nations can only have 1 bane placed on them at a time

src/engine/objects/Bane.java

@@ -231,6 +231,15 @@ public final class Bane {
                 return false;
             }
         }
+        if(targetCity.getGuild().getNation().getSubGuildList() != null) {
+
+            for (Guild subGuild : targetCity.getGuild().getNation().getSubGuildList()) {
+                if (getBaneByAttackerGuild(subGuild) != null) {
+                    PlaceAssetMsg.sendPlaceAssetError(player.getClientConnection(), 1, "This Nation Already Has a Bane Placed On It");
+                    return false;
+                }
+            }
+        }
         stone.addEffectBit((1 << 19));
         stone.setMaxHitPoints(stone.getBlueprint().getMaxHealth(stone.getRank()));
         stone.setCurrentHitPoints(stone.getMaxHitPoints());