Number of possible players:
Lieutenant Skat (from German Offiziersskat) is a fun and engaging card game for two players, where the second player is either live opponent, or built in artificial intelligence.
The game is played using a single deck of cards. Cards are shuffled and distributed amongst the players in such a way that half of them are face down and half of them are open. Each participant plays one of the open cards per turn. As soon as all the cards are played the round ends and points are calculated and awarded.