Return of the Mouse Commandos

The Fortress has been mice free for a year and half. I hoped that by killing all of them with the precision that only someone like me that is 1/4 German and all ninja could do, that it would forever deter others from ever trying to come back. Unfortunately, mice have a short memory. I don't think I cook enough in the fortress for a mouse to survive on my leftovers, but I do live in a townhouse