Diamonds is a trick-taking card game in which players collect Diamonds — not cards bearing that suit, mind you, but rather actual "Diamond Crystals" (acrylic crystals) included in the game.

What makes the game of Diamonds different from other trick-taking card games is that when you cannot follow suit you get a "Suit Action" based on what suit you do play. Suit Actions are also taken by the winner of each trick, as well as at the end of a full Round of play.