The deck consists of 81 cards varying in four features: number (one, two, or three); symbol (diamond, squiggle, or oval); shading (solid, striped, or open); and color (red, green, or blue). Each possible combination of features (e.g., a card with three striped green ovals) appears precisely once in the deck. There is always at least one UltraSet on the table.
If you click on four cards, which are UltraSet, they will disappear and be replaced by another ones. The faster you find it the more points you get. The object of the game is to get as many points as possible. "Find Set" will show you an UltraSet, but it will cost you 500 points. And if you select four cards and it is not an UltraSet - you've got 100 points penalty. Game ends when all cards from deck are gone and there are no UltraSets on the table.