Really awesome game! I love how there is a freedom to how you beat the puzzles. For example, on level nine I pinned the knight to the wall, but couldn't figure out how to get the archer down. Instead, I shot an ice ball at the pinned knight to make him drop, lowering my teammate to victory. The concept is really expanded upon to a great extent which I like.
My only complaint is that the controls are not my favorite. I would suggest using WASD to move and jump, S to switch, and J or enter to attack. Just a suggestion. Nice work!
Edit: I got a little more used to the controls when I played it again