Skat is the most popular card playing game in Germany, where 1/5th of the population know the rules and nationwide competitions are held. It is also popular in the USA.
Skat is played with a 32 card deck, 7,8,9, queen, king, 10, ace and jack in each suit. The trick taking game is played with 3 players. Players auction for the right to take the two remaining cards (the "skat"), define the trump suit, and play against the two other players. Getting tricks worth 61 or more out of 120 wins the game.
Despite being a card game, the factor of luck is small enough to qualify the game as a skill game - despite Germany's strict anti gambling laws, Skat can legally be played for money. To minimize the factor of luck, up to 35 games are played in one session. One can win one or two games by luck, but it requires skill to win an entire series.