Set Card game. The mathematics game of set. The deck consists of 81 unique cards that vary in four features across three possibilities: number of shapes (one, two, or three), shape (triangle, square, ball), shading (solid, striped, or open), and color (yellow, blue, or red). [1] Each possible combination of features (e.g., a card with [three] [striped] [blue] [square]) appears as a card precisely once in the deck.
In the basic game, three cards make up a "set", which a player collects by making sure each of those three cards has exactly the same matching feature or else all have a different feature. If two cards match in one of the four features, but the third card does not, then the three cards are not a "set" and the player is penalized instead of being able to collect.
