Uno Attack cards are a special variant of the popular children's card game specifically designed to work with a mechanical card launcher. It has slightly modified rules and features several new card types. There are two versions of Uno Attack, each with its own modifications.
The mechanical card launcher replaces the draw deck typically used in Uno. Instead of drawing a card, players must tap a button on the launcher. The launcher is equipped with a randomized trigger that ejects cards after an unknown number of button pushes.
In the first version of Uno Attack, the Draw Two and Wild Draw Four cards were replaced with cards that mandate players to hit the launcher's button. The Skip, Reverse and Wild cards were left unchanged. Mattel also added three new card types, the Wild Hit All, Discard All and Swap Hands.
The second version of the game dropped the Wild All Hit and the Wild Hit Fire, the card that replaced the Wild Draw Four. The newer version featured a redesigned launcher as well. The differences between the two are largely cosmetic, but the mechanics are essentially the same. The new launcher reportedly has a stronger motor and fires the cards more smoothly than its predecessor.