Alternate universe (fan fiction)

An alternative universe (AU, also known as an alternate universe, alternative timeline, alternate timeline, alternative reality or alternate reality) is the occurrence of canonical facts about the setting or characterization of a particular fictional universe being explored in a non-canonical way. These universes are often made unofficially, though elements of fan fiction are sometimes used in official, though usually non-canonical, storylines.

Stories that fall into this definition are usually "what-ifs", where possibilities arising from circumstances which do not occur in the original fictional universe are explored. For example, the premise of an alternative universe story may go something like this: "What would happen if character X was killed before event Y could happen?" Unlike regular fan fiction, which generally remains within the boundaries of the canon set out by the author, alternative universe fiction writers like to explore the possibilities of pivotal changes made to characters' history, motivations, or environment.

Authors and readers of AU fan fiction enjoy it for many different reasons, but there are several shared story types that exist within many fandoms:

Stories in this category follow the established canon before veering away at a crucial moment (similar in concept to many entries in Marvel Comics' What If series and DC Comics' Elseworlds series). An example of this is the Harry Potter story "All I Need ~ Drarry", by Wattpad user LostAllHope00, where the protagonist Harry Potter is placed in a relationship with a boy who is usually his enemy, Draco Malfoy. The Pokémon TV and video game series too has had its fair share of alternative universe fanfictions. One example notable for its popularity is "Blue Tears", a story in which the pokémon trainer Blue gets revenge on his rival Red after the latter's actions on the S.S. Anne led to the death of Blue's Raticate.

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