This classic card game was designed by George Parker himself, first introduced in 1906, and initially sold under an offshoot of Parker Brothers named The Rook Co. Rook requires trumps, bids, and taking tricks, just like conventional bridge. Rook, however, requires its own set of cards-four suits (red, green, yellow, and black) each with 14 numbered cards. In addition to the extra cards, the game contains a Rook card, always the trump card of lowest value. Two to six players can play at a time; the instruction booklet describes 16 variations of the game. The game has remained popular since its introduction.