I can't really comprehend how you made this one. It scares me. I discovered pretty much no bugs, you've successfully pulled off local multiplayer in a game jam, and the game is, most importantly, FUN. It might need a good coat of paint and a checkmate detector, and your adherence to the theme might be iffy, but those first two are things I couldn't possibly suggest were achievable in this timespan. I sincerely hope you make this into a larger thing- I could see it becoming the next 4d chess with multiversal time travel. Great job!