Editing Retroactive continuity (section)

===Subtraction===
Unpopular stories are sometimes later ignored by publishers, and effectively erased from a series' continuity. Later stories may contradict the previous ones or explicitly establish that they never happened.{{citation needed|date=January 2024}} In television, when a character is subtracted with a retcon, this is often known as "[[Chuck Cunningham syndrome]]," after a character from the series ''[[Happy Days]]'' that was retconned out of existence shortly through the series run,<ref>{{Cite web |last=Abramson |first=Dan |date=June 17, 2010 |title=The 13 Most Ridiculous Sitcom Mysteries Of All Time (PHOTOS) |url=https://www.huffingtonpost.com/2010/04/17/the-most-ridiculous-sitco_n_541532.html |url-status=live |archive-url=https://web.archive.org/web/20170404012114/http://www.huffingtonpost.com/2010/04/17/the-most-ridiculous-sitco_n_541532.html |archive-date=April 4, 2017 |access-date=April 20, 2020 |website=Huffington Post}}</ref> or "going to Mandyville," after [[Mandy Hampton]], a character that suffered a similar fate in ''[[The West Wing]]''.<ref>{{Cite news |last=Dyer |first=James |title=15 things you didn't know about ''The West Wing'' |url=https://www.empireonline.com/west-wing/thingsyoudidntknow.html |access-date=June 21, 2022 |work=[[Empire (magazine)|Empire]]}}</ref>

Notable examples of subtractive retconning include ''[[Terminator: Dark Fate]]'' (2019)'','' which is a sequel to the first two ''Terminator'' films and ignores the events of every other film in [[Terminator (franchise)|the franchise]], and ''[[Halloween (2018 film)|Halloween]]'' (2018), which is a sequel to only the [[Halloween (1978 film)|original film]] and disregards all the other sequels.

Stories that involve [[time travel]] can be used to undo the events of poorly received installments. After ''[[X-Men: The Last Stand]]'' (2006) faced criticism for abruptly killing off characters such as [[Cyclops in other media#Film|Cyclops]] and [[Jean Grey (film character)|Jean Grey]], its sequel, ''[[X-Men: Days of Future Past]]'' (2014), features the character [[Wolverine (character)|Wolverine]] traveling back in time to 1973 to prevent an assassination that, if carried out, would lead to mutant extinction. The result of this is a new timeline where Jean and Cyclops never died.<ref>{{cite web |url=http://www.rottentomatoes.com/m/x_men_days_of_future_past/news/1930516/critics_consensus_x-men_days_of_future_past_is_certified_fresh/ |title=Critic Consensus: X-Men: Days of Future Past is Certified Fresh |date=May 22, 2014 |access-date=May 26, 2014 |last=Ryan |first=Tim |website=[[Rotten Tomatoes]] |url-status=live |archive-url=https://web.archive.org/web/20140525043810/http://www.rottentomatoes.com/m/x_men_days_of_future_past/news/1930516/critics_consensus_x-men_days_of_future_past_is_certified_fresh/ |archive-date=May 25, 2014}}</ref>