Roshambo is a game where two participants use hand symbols for rock-paper-scissors.
Cartman's twist of the game involves both players kicking each other in the testicles until one falls and the other person standing is deemed the winner. This generally means the first person to go is guaranteed to win the game. It was introduced in Mecha-Streisand where Cartman plays the game with Pip to resolve their argument over discovering an arrowhead. Robert Smith later challenges Cartman when he won't return his walkie-talkie after Mecha-Streisand is defeated. In "Here Comes the Neighborhood", the boys are seen playing the game amongst each other after watching Token and the other rich kids playing polo.