The Uno (card game) World Championship is regarded as one of the fiercest card game competitions.
The popular Uno card game was invented near Cincinnati in 1971. It is played with a specially printed deck and is in the Crazy Eights family of card games. A game is won by accumulating 500 points through several hands. When a player is down to only one card, s/he yells “Uno!” to warn other players. Some Uno decks have special cards or themes. In all there are more than 135 different themed Uno decks.
The Uno World Championship is held annually in Moscow, Russia. Over 71 countries compete in the championship and it is regarded as one of the fiercest card game competitions. Players are known for displays of extreme endurance and concentration needed for long games. In 2011 the finals took over 5 hours to finish.