Keys "s"=save "l"=load "b"=back once
The Batak are a mostly-Christian people of Sumatra.
Pinned pieces cannot give check. The king can make any two-square leap, including a knight's move, on the first move. Later the rook move can complete castling. The king's pawn, if it advances one on its first move, can advance two on its second move. Discovered checkmate is a draw. I have not yet implemented the rule about a promoted piece moving diagonally backwards at once.
These are simple illustrations rather than strong opponents.
Bug reports? -- Thank you! Keep them coming!