Role-playing game system

A role-playing game system is a set of game mechanics used in a role-playing game (RPG) to determine the outcome of a character's in-game actions.

By the late 1970s, the Chaosium staff realized that Steve Perrin's RuneQuest system had the potential to become a "house system", where one set of game mechanics could be used for multiple games; Greg Stafford and Lynn Willis proved that theory by boiling down the RuneQuest rules into the thin 16-page Basic Role-Playing (1980).Hero Games used their Champions rules as the basis for their Hero System. The Pacesetter house system centered on a universal "action table" that used one chart to resolve all game actions.Steve Jackson became interested in publishing a new roleplaying system, designed by himself, with three goals for the system, that it be detailed and realistic, logical and well-organized, and adaptable to any setting and any level of play; this system was eventually released as GURPS (1986). The Palladium house system, a D&D-derived RPG system, ultimately encompassed all of the Palladium Books titles.Mekton II (1987) by R. Talsorian Games revealed for the first time the full-fledged Interlock System.

In 1990 Game Designers' Workshop released Twilight: 2000 second edition and decided to turn the Twilight: 2000 game system into their house system, an umbrella under which all future games would be designed.TSR's Amazing Engine was a universal game system, a simple beginner's system. In 1996, Hero Games partnered with R. Talsorian and decided to create a new, simpler rules system to attract new players, merging it with the Interlock game system and calling it Fuzion.Dragonlance: Fifth Age (1996) was built on TSR's new SAGA storytelling game system, which centered on resource management (through cards) rather than die rolls. TSR published Alternity (1997), another universal system, this one directed only toward science-fiction games.West End Games' MasterBook system had failed to catch on as a house system, so they decided to publish another, the D6 System, based on their most well-known and well-tested game system, Star Wars RPG.

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