The object of the game is to be the first player to build a complete leak-free pipeline, from your valve card to your spout card. The iron/lead pipe cards can 'leak' (via opponent sabotage), and be repaired with a wrench or a replacement pipe segment; the copper pipe cards never leak. The minimum number of pipe cards you need to place in between the valve and spout varies by the number of players. In versions that support up to 4 players: 2 players = 12 pipe cards 3 players = 10 pipe cards 4 players = 8 pipe cards In versions that support up to 5 players: 2 players = 15 pipe cards 3 players = 12 pipe cards 4 players = 10 pipe cards 5 players = 8 pipe cards