Keys "s"=save "l"=load "b"=back once
This is one of many variants. If you move one piece (not a pawn), you must move each of your other pieces of the same kind if you are able. If one piece (not a pawn) is captured, all pieces of that kind are removed. I omitted the rule about recaptures.
These are simple illustrations rather than strong opponents.
Bug reports? -- Thank you! Keep them coming!