I like the fact that this somehow feels like the game lemmings, but with a fun twist. At first it seemed as everything was just guess work, but after a while I figured out on how to use the environment to control my rat placement, actually i think with a bit more work, this could become a very interesting puzzle platformer. Great job!
One nit pick, I would have preferred if each rat had its own sound theme, different jumps per rat, maybe different characteristics (fat, thin, etc..) to bring more variety in the sound and potential play-styles.