In Uno Attack, each player starts with seven cards and must play a card with the same color, number or word as the previous card played. If a player has no card to play, he must activate the card launcher, which occasionally shoots cards at the player.
Before playing, each player draws a card from the deck. The one with the highest number is the dealer. After giving all players their cards, the dealer begins the discard pile by turning the top card of the deck face up on the card launcher.
As each player takes his turn, he rotates the launcher so that it points at him. If he cannot play and must activate the launcher, he must take all cards that shoot out at him into his pile. If the launcher does nothing, the turn is over. If another player yells "Uno" before the player with one card does, the player with one card must press the launcher button twice before the next player's turn.
Rather than the game ending when one player loses all his cards, the first player to reach 500 points wins. After getting rid of his cards, the player should count up the point values of the cards in the opponents' hands, adding them into his score.