So, a squirk on e4 can jump to c2, c3, c4, c5, c6, d2, d6, e2, e6, f2, f6, g2, g3, g4, g5, and g6. And the squirk on e4 can instead make a move like a rook. The object of the game is to first take a king, and then to mate the second king. However, as soon as he has lost one king, the other may not be moved in check. When this king is mated, his opponent has won.
Pawns can promote to queen, squirk, rook, knight, and bishop.
All other rules are as in usual chess . The squirk is probably slightly stronger than a queen. David Moeser, the inventor of the game, sent me more information on his game. The player can sac one royal in order to save the other. As in castling long in regular chess, the king moves to the bishop file and the far rook moves around it to the adjacent square.