History Main / ZeerustCanon

* ''VideoGame/BackToTheFutureTheGame'' runs into this with the 2011 PointAndClick video game. The final episode includes both UsefulNotes/XBox360 headsets (from the RealLife 2000s) and the Creator/{{Mattel}} Hoverboard (from the second film's 2015).

A work is a sequel or prequel to a work that is outdated in [[ScienceMarchesOn one way]] or [[FailedFutureForecast another]] but subsequent works have to keep the setting. Why? [[GrandfatherClause Because it's canonical]]. Some ways of working around this can include setting the story in an AlternateHistory, having a wide range of [[AnachronismStew fashions and technologies]], or invoking TechnologyMarchesOn for sequels that downplay this.

* ''Anime/MacrossZero''. ''Anime/SuperDimensionFortressMacross'', released in the early 1980s, had a unification war at the start of the 21st century. Comes the 21st century and ''Anime/{{Macross}}'' is still a franchise... let's use the war during the show anyway. On an even more fundamental level, the ''Macross'' landed on Earth in the far off future year of 1999. The Earth was scoured with Zentradi fire in the even further-off year of 2010. The landing of the ''Macross'' is the prime divergence point because its arrival (and the realization that there were potentially hostile aliens out there) is what ''started'' the Unification Wars, a point which can catch new viewers out because in ''Anime/{{Robotech}}'' it was what ''ended'' the Unification Wars.

* Creator/{{Leigh Brackett}}'s first Literature/EricJohnStark stories (published in the 1940's and 50's) had the character adventuring on [[VenusIsWet a Venus full of vast swamps and oceans]], and a Mars that, [[OnceGreenMars while arid and fallen from its ancient greatness]], still supported a vast human population. When Brackett returned to Stark in the 1970's, space probes had shown the other planets of our solar system to be barren of life (or at least life as we know it), so Brackett invented the planet Skaith, located in a different solar system, as a new setting for the stories. However, those stories still referenced Stark's childhood growing up on Mercury - even though an Earth-like Mercury was just as discredited as an Earth-like Mars or Venus, it was too important to Stark's character to be written out.

* ''VideoGame/RoboCopRogueCity'', made in 2023, is based on [[Franchise/RoboCop a series of sci-fi movies]] from TheEighties and keeps their distinctly '80s vision of the future, with regards to everything from big computer monitors to the titular protagonist's cybernetic enhancements to the [[TheQuincyPunk punkish criminals]] and street drugs.