Metagaming is a broad term usually used to define any strategy, action or method used in a game which transcends a prescribed ruleset, uses external factors to affect the game, or goes beyond the supposed limits or environment set by the game. Another definition refers to the game universe outside of the game itself.
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... In role-playing games, metagaming is a term often used to describe players' use of assumed characteristics of the game ... In particular, metagaming often refers to having a character act on knowledge that only the player has access to (such as tricking a Medusa to stare at a mirror when ...