Rock, paper, scissors, lizard, Spock
In "The Rothman Disintegration" (Episode 17, Season 5), Raj suggests that the inheritance of Professor Rothman's office be settled with a game of rock, paper, scissors, lizard, Spock.
What's that, you ask? "It's very simple. 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."
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