From Wikipedia, the free encyclopedia - View original article

  (Redirected from Rock-paper-scissors-lizard-spock)
Jump to: navigation, search
A diagram explaining the outcomes of the game
Another diagram, displaying clockwise from top: scissors, paper, rock, lizard, Spock
The normal form matrix of rock-paper-scissors-lizard-Spock. Rows represent available choices for player 1, columns those for player 2. Numbers in cells show utility (payoff) for player 1, player 2.

Rock-paper-scissors-lizard-Spock is an expansion of the classic selection method game rock-paper-scissors. It operates on the same basic principle, but includes two additional weapons: the lizard (formed by the hand as a sock-puppet-like mouth) and Spock[1] (formed by the Star Trek Vulcan salute). This reduces the chances of a round ending in a tie (from 1/3 to 1/5). The game was invented by Sam Kass with Karen Bryla, as "Rock Paper Scissors Spock Lizard".[2][non-primary source needed]

The game was mentioned in four episodes of The Big Bang Theory. According to an interview with Kass, the series producers did not ask for permission to use the game, but he was later referenced in the episode "The Rothman Disintegration" from the fifth season, for which he thanked them on his website.[3][self-published source?][2]


Each player picks a variable, then all players reveals their choices at the same time. The winner is the one who defeats the others. The rules of rock-paper-scissors-lizard-Spock are:

There are fifteen possible pairings of the five gestures. Each gesture beats two of the other gestures and is beaten by the remaining two. In a tie, the process is repeated until a winner is found. The original rules (rock beats scissors, scissors beats paper, paper beats rock) remain the same.


  1. ^ "... and paper scissors". The Times. June 11, 2005. Archived from the original on May 31, 2010. Retrieved 2010-11-04. 
  2. ^ a b "Rock Paper Scissors Spock Lizard". Sam Kass. Retrieved 2010-11-04. 
  3. ^ "The True Story behind RPS, Lizard, Spock". Archived from the original on May 19, 2012. Retrieved January 10, 2014.