Isometric Chess is part of the beta for my game, Deckmate! If you'd like to try it out for yourself, join the Discord server linked in the description of the long-form video.
I went down to rabbit hole via long chest, and I went through five chess five chess with time, travel, infinite chess, and then tall, chess circle, chess hexagon, chess, and then checkers and chess on the same board
There actually was a king last time, it was just out of frame 😂 But the real answer is that the game ends if there aren't kings on the board, and I was too lazy to make an override
The only special rules are that they cannot move to an occupied square when switching dimensions (meaning no captures), and kings cannot switch dimensions while in check
