In every turn, select a rat and move with it. You can open chests, collect items, or kill enemy rats. If you move to a tile with an enemy on it, you kill it. If you collect an item, you can use it (throw), move with it or drop it to different tile. Your goal is to kill all enemy rats in every level.
As for applications in company's office: if you saved any paper in previous level, you can make them. The more you demand, the bigger the chance to be rejected.