Sealed Evil in a Can/Playing With

Basic Trope: A Big Bad is sealed away, rather than being killed outright.
 * Straight: The Evil Overlord seeks to unleash his master, sealed beneath the earth 10,000 years ago.
 * Exaggerated: The Ultimate Evil is sealed inside the planet itself, and freeing him alone will entail an Earthshattering Kaboom. Which the people trying to free him are all too happy to provide.
 * Justified: Killing the Ultimate Evil was beyond the ability of the ancients (he's just too powerful).
 * Alternately, the imprisonment was intended to be a temporary measure, but the Precursors were wiped out before they came back with a more permanent solution.
 * Alternately, the Ancients thought the Ultimate Evil was defeated for once and for all, but in fact it was merely dormant, waiting for an opportunity to wreak havoc once again.
 * Alternately, killing the Ultimate Evil was possible, but it turns out that he is resurrectively immortal and that As Long as There Is Evil, he will always come back, so sealing him was the only way to keep him from wreaking havoc upon the world.
 * Inverted: See Sealed Good in a Can.
 * Our world is sealed in a can to be protected from the Ultimate Evil infesting the universe.
 * Or: rather than make a can, the Ultimate Evil is sent onto exile, and a fence is built to keep it out.
 * Subverted: The Ultimate Evil refuses to come out; he likes it better in his can.
 * Alternately, the centuries trapped in a can haven't been kind to the Ultimate Evil, and he's not the world destroying Badass he once was.
 * The Big Bad releases the Ultimate Evil, and the Ultimate Evil disagrees with the idea that he owes the Big Bad a favor now.
 * The Ultimate Evil has mellowed out in the centuries its been imprisoned and has performed a Heel Face Turn.
 * Double Subverted: The Ultimate Evil refuses to come out; he likes it better in his can. The current Big Bad forces him out as part of her plan to rule the world; the Ultimate Evil decides to destroy all of existence in revenge for having his nap interrupted.
 * Parodied: The can the Ultimate Evil is sealed in is a Campbell's Soup can, label and all.
 * Deconstructed: What's in the can wasn't evil at all, merely an immensely powerful sentient being sealed by the Ancients for no good reason. It went mad in the interim, and now seeks only for someone to end its tortured existence.
 * Reconstructed: What's in the can wasn't evil at all, merely an immensely powerful sentient being sealed by the Ancients for no good reason. It went mad in the interim, and now seeks only to end all of existence.
 * It was a Well-Intentioned Extremist and the Ancients are only the bad guys from its perspective. They didn't want to seal it away but had no other choice.
 * Zig Zagged: The Ultimate Evil is unsealed, but it turns out it was a perfectly innocent being driven mad by its imprisonment; a Cooldown Hug mixed with some Epiphany Therapy is all it takes to stop its Roaring Rampage of Revenge. Then it turns out that it was sealed because it had omnipotence but no concept of right and wrong; now that it's been cured of its insanity, it's back to warping reality for kicks and giggles. Someone takes advantage of its childish nature, though, and manages to distract and seemingly tame it by teaching it to play a game. Then it starts rewriting reality into a colossal version of said game...
 * Averted: The Ultimate Evil was, in fact, destroyed for good by the Ancients.
 * Enforced: "We need to explain why the villain hasn't attempted to avenge himself on the kingdom before, so we had to have him escape from a magical prison built specifically for him."
 * Lampshaded: "And, like a hundred other things, the Ancients leave us a really huge problem they could've fixed the first time around."
 * Invoked: The Ultimate Evil made sure he couldn't be destroyed by the Ancients by sealing himself in a can, confident that he would be awakened in the future long after his enemies had all died off.
 * Alternately: The Ultimate Evil succeeds in destroying civilization. Then he seals himself in a can so he doesn't get bored waiting for another civilization to destroy.
 * Defied: The Ancients not only sealed away the Ultimate Evil, they also made sure he could never come back, possibly by launching him into the sun.
 * Discussed: "I thought only in bad sci-fi stories would there be Precursors worthy of the name so utterly stupid as to leave their enemies imprisoned, rather than actually eliminate the problem, but these guys really were both that powerful and that stupid. Well, I'm suitably impressed."
 * Conversed: "Why do they always 'seal away' these Ultimate Evils in these shows? Couldn't they, just once, kill the guy and be done with it?"

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