Spades

Spades is the partnership trick-taking game built around a promise. Four players in two partnerships each bid the number of tricks they expect to take; a side that lands its combined contract scores ten points a trick bid, one for each trick over, and a side that falls short loses the lot. Spades are always trump — the suit gives the game its name — and they may not be led until one has been played on another suit's trick.

Zero is a bid of its own. Nil is a promise to take no tricks at all, worth a hundred points made and minus a hundred failed, and covering a partner's nil is half the art of the game. You play with a computer partner against two computer opponents at three strengths, or open a table and send the room code to three friends.