The game is an expansion on the game Rock, Paper, Scissors. Each player picks a variable and reveals it at the same time. The winner is the one who defeats the others. In a tie, the process is repeated until a winner is found.
Scissors cuts Paper Paper covers Rock Rock crushes Lizard Lizard poisons Spock Spock smashes Scissors Scissors decapitates Lizard Lizard eats Paper Paper disproves Spock Spock vaporizes Rock (and as it always has) Rock crushes Scissors