A rook promotion is something regular chess players will need to do to prevent stalemate, but it isn't that common where it is required (as opposed to someone who could win with a queen instead but it is trickery so beginners should go for a rook ). A Knight is the better promotion choice often enough that you should study tactics that lead to it, while a rook it is enough to do a stalemate check before promoting. There are tactics that only a bishop wins, but they are things you study for fun, not because you expect them.