Walter Montego: You win a game of superchess by checkmating the king or emperor. If they are both in the game, you can give a doublecheck, which means that both are in check. The only way to uncheck your emperor AND king is by eliminating the piece(s) power that give check. There are some possibilities for it: capturing, freezing or protecting your royals with a protecting piece as the Nymf and the Angel.

I think board size is negiotable, but maybe Fencer will add four variants: 8x8, 10x8, 8x10 and 10x10. The set of pieces is pure negotiable. But here I think, the creator of a game chooses the set and if you agree with that, you play the game.

Link: www.superchess.nl or if it does not work, www.superschaak.nl and click on the english flag, because that site is mostly in dutch.