Blink

The two-minute-long, two-player card game Blink - which was originally published as Speed - bills itself as the fastest game in the world.

Without taking turns, players race to empty their hands by matching the color, shape, or number of symbols on a card in their hand to the top card of either of two discard piles in the center of the table. As soon as a player lays down one card, they can draw another, up to the hand size of three cards. If both players can't play, they each simultaneously draw a card from their deck directly onto a discard pile, then continue play. The first player to empty their hand and draw pile wins.

Blink includes a variant for three-player games: Deal each player a third of the deck, start a discard pile in front of each player, and discard only onto the discard piles in front of other players. (The rules also claim a four-player variant, but this is a tournament format, not for four players competing at the same time.)