History SealedEvilInACan / WesternAnimation

* ''WesternAnimation/{{Animaniacs}}'': The Warner Brothers (and their sister Dot) were Sealed Zany in a Water Tower. In this case, it was more Sealed ''Chaos'' in a Can. The Warners keep breaking loose throughout the series and annoying people.

* ''WesternAnimation/TheGhostAndMollyMcGee'': While [[FateWorseThanDeath The Flow of Failed Phantoms]] was used to imprison pretty much any ghost who displeased [[BigBad The Chairman]] regardless of what they had done, [[spoiler:after his destruction]] it turns out that it had also been used to imprison some genuinely dangerous ghosts. Such as The Frightmares, evil ghosts who thrive on chaos, and Lord Doom, a ghost who’s so evil and powerful he scares even the other inhabitants of the Ghost World. [[spoiler:The Frightmares are eventually imprisoned once again, this time by [[WhoYaGonnaCall The Chens]] ghost catching device. And as for Lord Doom, he’s cursed by Scratch into being trapped in a doll. Which he [[HeelFaceTurn surprisingly adjusts to rather well.]]]]

* ''WesternAnimation/TheGhostAndMollyMcGee'': While [[FateWorseThanDeath The Flow of Failed Phantoms]] was used to imprison pretty much any ghost who displeased [[BigBad The Chairman]] regardless of what they had done, [[spoiler:after his destruction]] it turns out that it had also been used to imprison some genuinely dangerous ghosts. Such as The Frightmares, evil ghosts who thrive on chaos, and Lord Doom, a ghost who’s so evil and powerful he scares even the other inhabitants of the Ghost World. [[spoiler:The Frightmares are eventually imprisoned once again, this time by [[GhostHunters The Chens]] ghost catching device. And as for Lord Doom, he’s cursed by Scratch into being trapped in a doll. Which he [[HeelFaceTurn surprisingly adjusts to rather well.]]]]

* ''WesternAnimation/TheOwlHouse'': Later episodes of the second season reveal [[Characters/TheOwlHouseOther the Collector]] is imprisoned [[spoiler:in a sphere inside the In-Between Realm, and he's actively seeking to escape with Belos' aid. Although this is later subverted as the Collector is ObliviouslyEvil at worst and [[MisplacedRetribution wasn't even responsible for what he was locked away for]].]]

* ''WesternAnimation/TheOwlHouse'': Later episodes of the second season reveal [[Characters/TheOwlHouseOther the Collector]] is imprisoned [[spoiler:beneath the Titan and/or in a sphere inside the In-Between Realm, and he's actively seeking to escape with Belos' aid]].

* ''WesternAnimation/LegionOfSuperHeroes'', "Phantoms": Due to TimeTravel, Franchise/{{Superman}} accidentally unseals an evil that, it's implied, his future self [[TimeTravelTenseTrouble sealed/will seal]] a thousand years beforehand.

** The Imperium which invaded Mars centuries ago. They were defeated and locked inside a vault by J'onn J'onzz, [[LastOfHisKind last of the Martians]]. In modern times, human astronauts accidentally released the Imperium [[AlienInvasion who set their sights on Earth]].
** Hades, Greek God of the Underworld. Released by Felix Faust in the hopes that Hades will grant him "ultimate knowledge" in return. Hades naturally betrays Faust by [[spoiler:causing him to instantly age to an old man since "Ultimately, pain and suffering are all humans will ever know."]]
** The "Enemies of Man," a race of serpent-men who had fought early man at the beginning of time voluntarily sealed themselves in a crystal when they realized they were losing the war. The crystal would have allowed the serpents to possess anyone who held it, allowing the Enemies to exact revenge on an unsuspecting mankind at a later date. Fortunately, early humans witnessed the ceremony, and built a forbidden temple around the crystal, posting a guard to keep it from coming in contact with anyone. Naturally this didn't work.

** The corrupted gems when they get bubbled. Centipeetle gets freed trice both by Steven but, before she gets retrapped the first time, she's a Sealed Good in a Can at this point and is permanently freed the second time.

** ''WesternAnimation/SonicTheHedgehogSatAM'': In one episode, Robotnik steals a computer of magic spells from the [[HeelFaceTurn formerly evil]] wizard Lazar, and Sonic attempts to get it back. When asked why he can't just destroy the computer, Lazar says that would release all the evil it contains.
** In the ''WesternAnimation/SonicBoom'' episode, "Closed Door Policy", Amy sells all of Sticks' possessions at a yard sale. This includes a surfboard blocking the entrance to the underground lair of the Froglodytes, a race of frog-like warriors. When the entrance is unblocked, the Froglodytes escape, capture Sticks, and attempt to [[HumanSacrifice sacrifice her to their idol god]]. Thus, it's up to Sonic and his friends to travel to the Froglodytes' underground lair to save Sticks.

* ''WesternAnimation/AdventureTime'': Marceline's father, Hunson Abadeer, is sealed in the Nightosphere. Finn [[NiceJobBreakingItHero frees him, not knowing how evil he was]]. In the end, Finn manages to seal him back into the Nightosphere. Even worse is [[OmnicidalManiac the Lich]], the UltimateEvil who was imprisoned inside amber within a great tree by the legendary hero Billy. He finally broke free during the season 2 finale.

** [[UltimateEvil The Overlord]] becomes this in season 3 when his essence is sealed in a hard drive.

* ''WesternAnimation/TheSmurfs'': Done a few times.

* ''WesternAnimation/{{Ninjago}}'': A common way of introducing villains:

** [[spoiler:Qilby]] was imprisoned in a BlankWhiteVoid by his brothers thousands of years ago, as punishment for his crimes against the Eliatropes and to permanently contain him despite his immortality. He's accidentally freed in Season 2 and sets about resuming his original plans at the World of Twelve's expense, only to be defeated by Yugo, after which the latter sends him back into the White Dimension.