Haaahah! This is really good! I like how you were able to adapt the different chess pieces into this genre - the way the knights thud as they jump the way the bishops zip in from across the board. It's very good. Once I internalized that "en passant" really wanted me to *pass* the enemies and not go through them, I started doing much better.
I love the little profile picture of our rambo pawn.
The victory lap ending level is great, too. It's always fun when there's a surprise final step at the end.