Yo. This is awesome. With some touches to SFX and making some QOF changes, this is interesting AND, as a bonus, with a passable finish. I really liked the pace of the game and can't wait to get a friend to try out PvP with!
If I may make some suggestions: having piece king-damage values or basic movement behavior show up while hovering over a piece might be nice, and instead of shading the area where you can't play, either do that and brighten where you can play or just brighten where you can play. These changes will assist accessibility-wise for players new to chess fundamentals (and, uh... I just kept passing the turn, thinking there was something more to it, I guess assuming that the rules were that much different compared to chess ;_;).
Among my favorite entries that I've seen so far. Nice. :)