During each round, one of the players takes on the role of Hall Monitor (the Catcher) - their aim is to catch the other penguins (the Runners), who are all trying to collect the fish hanging from doors. Players gain victory points by catching others or by collecting fish. When either the Catcher has caught all of the Runners, or any of the Runners have collected 3 Fish of their color, the round is over.
The game is over when every player has been the Catcher once. The player with the most victory points (fish) is declared the winner!