Classic: Standard Chess rules.
Fischer 960: Randomized starting pieces.
Fog of War: You only see what your pieces can attack.
Stargate: Teleportation squares appear on the board.
Ubiq: Pieces randomly transform after moving.
Simple Chaos: Random back rank.
Total Chaos: Pieces scattered everywhere!
Murder King: All pieces look like Kings. Find and kill the Royal one (marked in Gold).