Great game, charming art and animations! The level transitions were cool too. It's also nice to have the enemy not kill the player when touched.
I would be great to have some sort of feedback when controlling/releasing the monsters. 'K' can be used to make the archer shoot even when not controlled. The spikes are a bit fast, was it intended so that the monster and player cannot cross it at once?
Still, it's a fun game. Great job on it!