Keys "s"=save "l"=load "b"=back once
Origins unknown. Popular in California in the 1970's. Place your last unit on the board after you place your last empty square, and before you move any empty square. A drop that produces checkmate loses.
Bodlaender's Chess Variants
Ed's Chess Variants
These are simple illustrations rather than strong opponents.
Bug reports? -- Thank you! Keep them coming!