My Night Job

Having a room stomped means there are a large amount of enemies in that one room and they are trying to destroy it. You will be alerted to a room being stomped by it turning yellow and red on your map (and occasionally it will zoom into that room to show you). You will probably get this one without even trying as it is hard to keep less than 10 rooms being stomped the longer you play due to the increase in enemies. If for some reason you don't, then start a game and just stay in one room killing any enemies that pop up in it and let the rest of the house be taken over. Eventually you will get 10 rooms being stomped and with that the trophy will pop.