History UnwittingInstigatorOfDoom / TheDCU

* ''ComicBook/{{Superman}}'': In ''ComicBook/TheLivingLegendsOfSuperman'', a defense robot watching over a mining outpost located at the rim of the universe mistakes a meteor shower for an enemy raid and shoots a barrage of atom particle destroyers. The APD missiles explode too near the edge of the universe, tearing a rift in the fabric of time and space which starts destroying the cosmos.

** In ''[[ComicBook/BatmanThreeJokers Three Jokers]]'', [[spoiler:it's revealed that ComicBook/TheJoker's pregnant wife shown in ''ComicBook/TheKillingJoke'' never actually died, having been FakingTheDead the entire time after snitching to the GCPD about the Ace Chemicals heist and gone into witness protection because [[DomesticAbuse she was afraid of him]]. This made her directly responsible for the creation of one of Earth's most dangerous supervillains, as she was the one who made the Comedian feel [[StrawNihilist as though he had nothing to lose]] and [[CreateYourOwnVillain sicced Batman on him]]. However, the canonicity of this is [[FlipFlipOfGod ambiguous at best]].]]

* In ''Franchise/TheFlash'', the Allens come to a doctor to deliver their twins, the same time as the Thawnes are expecting a delivery as well. The Thawne child died in childbirth, and, out of guilt, the doctor gave one of the Allen twins to the Thawnes while fabricating a lie to his real parents that he died. Malcolm "Thawne" grows up in a dysfunctional, criminal family, and when he learns of his true parentage, [[EvilTwin comes to resent his twin brother Barry as a result]]. While Barry successfully heads a mostly-familial legacy of superheroes, Malcolm would become the ancestor to multiple supervillains (the second Reverse Flash, Captain Boomerang II, Inertia, not to mention multiple other descendants that bear Malcolm's "Cobalt Blue" villain moniker), creating one of the largest FeudingFamilies in the DCU.

* In ''ComicBook/BatmanThreeJokers'', [[spoiler:it's revealed that ComicBook/TheJoker's pregnant wife shown in ''ComicBook/TheKillingJoke'' never actually died, having been FakingTheDead the entire time after snitching to the GCPD about the Ace Chemicals heist and gone into witness protection because [[DomesticAbuse she was afraid of him]]. This made her directly responsible for the creation of one of Earth's most dangerous supervillains, as she was the one who made the Comedian feel [[StrawNihilist as though he had nothing to lose]] and [[CreateYourOwnVillain sicced Batman on him]]. However, the canonicity of this is [[FlipFlipOfGod ambiguous at best]].]]

* ''ComicBook/CrisisOnInfiniteEarths:'' Krona, as mentioned down below, already got the ball rolling when he first attempted to look at the dawn of the universe, but it's the man who'd become Pariah who kick-starts the plot proper. Having made his world a utopia, he decided to try and find out the origins of the universe, despite everyone telling him not to. He ignores them. His attempt outright destroys his entire universe ''by accident''... and the resulting imbalance proves enough to wake the Anti-Monitor from his eons long slumber, whereupon he starts destroy every universe ever. (Needless to say, some of the survivors are just a little pissed when they learn this fact.)

* One for villains everywhere, across nearly all incarnations: [[SmallRoleBigImpact Joe Chill]], a simple mugger, for [[DeathByOriginStory unwittingly]] [[YouKilledMyFather creating]] {{Franchise/Batman}}.
* In ''ComicBook/BatmanThreeJokers'', [[spoiler:it's revealed that ComicBook/TheJoker's pregnant wife shown in ''ComicBook/TheKillingJoke'' never actually died, having been FakingTheDead the entire time after snitching to the GCPD about the Ace Chemicals heist and gone into witness protection because [[DomesticAbuse she was afraid of him]]. This made her directly responsible for the creation of one of Earth's most dangerous supervillains, as she was the one who made the Comedian feel [[StrawNihilist as though he had nothing to lose]] and [[CreateYourOwnVillain sicced Batman on him]]. However, the canonicity of this to the main ComicBook/DCRebirth timeline is [[FlipFlipOfGod ambiguous at best]].]]

* The race known as the [[ComicBook/GreenLantern Guardians of the Universe]] practically has this as its ''[[PlanetOfHats hat]]''.
** One member of their race, Krona, attempting to settle the Origin Question (basically, why is there a universe and why is there life in it and specifically why are there Oans/Malthusians in it), [[ComicBook/CrisisOnInfiniteEarths introduced Evil (or at least Entropy) into the universe]]. Later retcons change it so that he instead splintered the universe into the multiverse, unleashed the Anti-Monitor and dragged Volthoom to Oa.

** Really, anytime something in the DC Universe is going very badly on a cosmic scale, the Justice League could save themselves some detective work by starting with the assumption that it's at least related to something that either Darkseid did on purpose or the Guardians did by accident.
* In ''ComicBook/TheMultiversity'', Ultra Comics is [[spoiler:exploited by the Gentry as a means to infiltrate the multiverse]]. While he manages to [[spoiler:seal Earth-33 off from them]], he's ultimately unsuccessful in [[spoiler:defeating the villains]].
** Toward the end, it turns out merely saying the words "[[spoiler:S.O.S.]]" summons the Gentry into the universe of whoever says it. So anyone who says it serves as one of these.

* In ''ComicBook/BatmanThreeJokers'', [[spoiler:it's revealed that in ComicBook/DCRebirth ComicBook/TheJoker's pregnant wife shown in ''ComicBook/TheKillingJoke'' never actually died, having been FakingTheDead the entire time after snitching to the GCPD about the Ace Chemicals heist and gone into witness protection because [[DomesticAbuse she was afraid of him]]. This made her directly responsible for the creation of one of Earth's most dangerous supervillains, as she was the one who made the Comedian feel [[StrawNihilist as though he had nothing to lose]] and [[CreateYourOwnVillain sicced Batman on him]].]]

* In ''Franchise/TheFlash'', the Allens come to a doctor to deliver their twins, the same time as the Thawnes are expecting a delivery as well. The Thawne child died in childbirth, and, out of guilt, the doctor gave one of the Allen twins to the Thawnes while fabricating a lie to his real parents that he died. Malcolm "Thawne" grows up in a dysfunctional, criminal family, and when he learns of his true parentage, comes to resent his twin brother Barry as a result. While Barry successfully heads a mostly-familial legacy of superheroes, Malcolm would become the ancestor to multiple supervillains (the second Reverse Flash, Captain Boomerang II, Inertia, not to mention multiple other descendants that bear Malcolm's "Cobalt Blue" villain moniker), creating one of the largest FeudingFamilies in the DCU.

** To combat evil ''and'' the Manhunters, they decided that another Corps was the way to go, this time the Green Lantern Corps. Noble in principle, but they also decided to [[SealedEvilInACan seal the Fear Entity inside the artifact giving the Green Lanterns their power]]. That [[ComicBook/ZeroHourCrisisInTime didn't work out so well either]].

** To combat evil ''and'' the Manhunters, they decided that another Corps was the way to go, this time the Green Lantern Corps. Noble in principle, but they also decided to [[SealedEvilInACan seal the Fear Entity inside the artifact giving the Green Lanterns their power]]. That [[ComicBook/ZeroHour didn't work out so well either]].