Campaign setting (Dungeons & Dragons)

A campaign setting is usually a fictional world which serves as a setting for a role-playing game or wargame campaign. A campaign is a series of individual adventures, and a campaign setting is the world in which such adventures and campaigns take place. Usually a campaign setting is designed for a specific game (such as the Forgotten Realms setting for Dungeons & Dragons) or a specific genre of game (such as Medieval fantasy, or outer space/science fiction adventure). There are numerous campaign settings available both in print and online. In addition to published campaign settings available for purchase, many game masters create their own settings, often referred to as "homebrew" settings or worlds.

The use of the term "world" in describing a campaign setting is loose, at best. Campaign worlds such as the World of Greyhawk detail entire cosmologies and timelines of thousands of years, while the setting of a game such as Deadlands might only describe one nation within a brief segment of alternate history.

There are three primary types of campaign setting:

Setting genres have touched on every genre of high-action fictional storytelling from role-playing's roots in fantasy to science fiction in settings such as Traveller to horror in the World of Darkness. Even modern-day spy thriller-oriented settings such as Spycraft have been introduced.

A small number of campaign settings fuse two or more genres in a single game. In GURPS Infinite Worlds, for example, the characters play "Infinity Patrol" agents who travel to alternate worlds. Shadowrun combines fantasy with cyberpunk, Castle Falkenstein draws on fantasy and steampunk elements, and Torg mixes fantasy, science fiction, pulp and horror elements while Feng Shui combines Chinese historical fantasy with kung fu action tropes and dystopian science fiction.

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Wikipedia