Chess++

With a new piece, a whole new moveset, and a new dimension, Chess++ is the most big-brain game you'll ever play.

Get started by going through the tutorial. It will teach you the rules and the new moves for each of the pieces. Afterwards, get some practice by playing against the easy CPU. Once you beat that, really challenge yourself with the hard CPU. If you've got a friend willing to play, challenge them as well!