House rules

House rules are rules applying only in a certain location or organization. Bars and pubs in which games take place frequently have house rules posted. For example, it is a house rule in United States Air Force officers' clubs that if an officer enters the club wearing headgear and is officially noticed (i.e., the bell near the bar is rung), the entering officer must buy a round of drinks for the bar.

In households, house rules are rules set by the head of the family, generally to be followed by children.

House rules are used in board games such as Monopoly. Generally these are either modifications or additions of new rules to the existing ruleset of the game, such as getting double the amount of money when landing on GO, or receiving money when landing on Free Parking.

A common use of the term is in role-playing games to signify a deviation of game play from the official rules. The usage of house rules is encouraged in a number of official game materials, as a way to personalize the game. Many other games do not explicitly encourage house rules, although house rules are commonly used in casual settings. Games that are played in tournaments typically have very explicit official tournament rules so that house rules are unnecessary. The anime-based RPG Mekton refers to house rules as "changing the laws of physics."

House rules can range from the tiniest of changes or additions to substantial deviations that alter the entire game play, depending on the imagination of the players. Most groups have house rules to some extent. In miniature wargaming, house rules may be used to represent equally unofficial miniature conversions, or can be used as scenario specific rules. House rules date back to the earliest days of role-playing: the original edition of Dungeons & Dragons suggested that players should have a copy of the Chainmail historical wargame for measurement and combat rules, and even more confusingly, it also presumed ownership of the Avalon Hill game Outdoor Survival (at the time, Avalon Hill was a competitor to D&D's publisher, TSR, Inc.; later, TSR and Avalon Hill would both come under the Hasbro/Wizards of the Coast umbrella). Since many players who purchased D&D did not own copies of Chainmail or Outdoor Survival, they simply made up rules to cover the holes in D&D; many of these house rules later became the basis for Advanced Dungeons & Dragons.

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