alternate universe
Used for hypothetical, non-canonical situations, such as exploring the implications of a deceased character still being alive (a.k.a. what ifs, WIs or alternate timelines) or a radical shift in setting like fantasy to urban (a.k.a. alternate universes, AUs). Some copyrights such as Undertale and OMORI are notable for having a large amount of fanmade AUs.
See also
The following tags are aliased to this tag: what_if (learn more).

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