I am impressed with this one. Not only you did the art during the jam, you also made a (mostly) functional AI for the game.
This checkers variant is fun to play and adds quite a depth to the game. I searched a bit to see if it already exists and found nothing, so congratulations for the idea!
The game is pretty much complete, the only thing I could say that is missing would be online play, but thats a low blow for a jam game.
Good job!