Keys "s"=save "l"=load "b"=back once
Origins unknown. King and Queen both move two spaces in a line straight or diagonally, and do not jump. Pawns move as queens, with no promotion. You win by capturing both king and queen.
I programmed this so that it starts calling "Check" or "Mate" as appropriate after either king or queen has been captured.
These are simple illustrations rather than strong opponents.
Bug reports? -- Thank you! Keep them coming!