History Main / KryptoniteRing

* ''WesternAnimation/SilverHawks'': Each of the SilverHawks has an emergency off-switch to be used if any of them went berserk for unforeseen reasons.

** There is another weapon in the 21st Century that can't be shut down effectively in America: the Internet. As the Internet is not controlled by the federal government but privately run by telecom businesses, any attempt to turn the United States of America into some Dictatorship of the New World Order would be set back by activists, especially if some of the activists turned out to be hackers!

* Franchise/XMen:

** Subverted in Pre-Crisis story ''World's Finest'' #176 in which Batman appears to have Kryptonite gloves, but in reality they are fake. Curiously, before he reveals that they are props, no one -not even ComicBook/{{Supergirl}}- questions why he has something that can kill his best buddy.

*** In ''ComicBook/TheSupergirlFromKrypton'' Batman uses a chunk of Green-K to knock [[Comicbook/{{Supergirl}} Kara]] out and bring her to the Batcave. Later, [[spoiler:Superman]] of all people uses a kryptonite ring to [[spoiler:knock a brainwashed Kara out]].

** In ''ComicBook/ElseworldsFinestSupergirlAndBatgirl'', ''ComicBook/LexLuthor'' has a Kryptonite ring that he plans to use against ''ComicBook/{{Supergirl}}''... until ''ComicBook/{{Batgirl}}'' steals it from him and takes it to a lead-lined vault, saying "I see it as insurance... which I hope I never need to use."

* ''Series/KamenRiderBuild'': [[ScienceHero Sento]] created an anti-hazard switch that he handed to [[FamilyOfChoice Misora]]. She was supposed to use it in case he lost control of [[SuperpoweredEvilSide Hazard]] form and there wasn't anyone to stop him. He told her that it will just knock him out of [[HenshinHero transformation]]. She correctly deduces that this is not all and manages to make tell her the whole thing. It will also destroy the Build Driver and [[DrivenToSuicide kill]] him. She is [[WhatTheHellHero very]], ''[[ANgerBornOfWorry very]]'' mad at him for making her promise she will murder him if the need arises.

* In ''Series/BuffyTheVampireSlayer''/''ComicBook/{{Supergirl}}'' crossover ''Fanfic/TheVampireOfSteel'', Supergirl lends her friends a chunk of Kryptonite in the event that things go south during the FinalBattle.

** The video game ''VideoGame/InjusticeGodsAmongUs'' takes this a step further; [[spoiler: In Superman's ending, it's revealed that the Regime-Superman's ease at conquering the world only made him even more terrified of what could happen if he ever lost control of himself. He makes sure this doesn't happen by having a Kryptonite ''bomb'' implanted by his heart, which will instantly kill him should this happen. The other members of the Justice League all take turns carrying the detonator for it. Except for Batman, who was denied a shift.]]

[[folder:Fanworks]]

* In ''Series/The100'' fic “[[https://www.fanfiction.net/s/13117218/1/Twisted-Steel Twisted Steel]]”, Clarke and Anya first bond as allies rather than enemies when Clarke has to ask for Anya’s help in removing her [[ArtificialLimbs artificial arms]], as the limbs suffered water damage during their escape from Mount Weather. Anya explicitly tells Clarke that there’s no shame in seeking aid from another, but also thanks her for the trust she’s shown Anya in revealing such a weakness as she demonstrates how to remove the limbs from her body.

[[caption-width-right:300:Nothing says true friendship better than to give your buddy the only thing that can kill you. [[note]] But let's be honest, Franchise/{{Batman}} [[CrazyPrepared already had kryptonite.]] [[/note]] ]]

[[folder: Comic Books ]]

** This is also inverted by the end of ''WesternAnimation/TheBatman'': Batman gives each member weapons that simulate each WesternAnimation/JusticeLeague member's weaknesses because aliens have invaded and copied their powers. They call him out on being so paranoid, until Superman steps forwards and [[ProperlyParanoid cites the time he was mind controlled in a previous episode]].

** To a lesser extent, the ''Comicbook/{{Shazam}}!'' Captain Marvel is employed occasionally as the one superhero tough enough to take on a controlled Superman if necessary. Or rather, he's tough enough to stall Supes in a fistfight long enough to call his magical lightning enough times to knock out his Kryptonian foe[[note]]Most forms of magic are able to bypass Superman's NighInvulnerability and damage him just like a de-powered kryptonian. As for how the Kryptonite Ring trope comes into play: Superman isn't going to tell just anyone this fun little fact, but he can usually trust the goody-two-shoes Captain Marvel[[/note]]. Altough, at least in [[ComicBook/KingdomCome one occasion]], it was ''Captain Marvel'' the brainwashed one, not Superman.

** In ''ComicBook/AllStarSuperman'', the Man of Steel helped Leo Quintum make three, including a Kryptonite weapon, a Phantom Zone Kill Sat and a super serum that can temporarily turn a person into Doomsday.

* In the BackStory of ''ComicBook/ExMachina'', The Great Machine (now the mayor of New York City) gave his two {{Secret Keeper}}s devices to cancel-out his ability to talk to machines. As was his habit, he explicitly referenced the Superman mythos as he did so. As we later learn [[spoiler:it's just junk made out of old garage door openers and doesn't affect his powers at all. He lied and gave them to his {{Secret Keeper}}s so that, if they ever betrayed him or were forced to turn against him, their plotting would depend on something that doesn't work. (Though a major plot hole is that it did work in the first story arc.)]].

[[folder: Fanworks ]]
* In ''Series/BuffyTheVampireSlayer''/''ComicBook/{{Supergirl}}'' crossover ''Fanfic/TheVampireOfSteel'', Supergirl lends her friends a chunk of Kryptonite in the event that things go South during the FinalBattle.

[[folder: Film ]]

* In ''Film/AvengersAgeOfUltron'', Iron Man and Bruce Banner discuss on how they developed "Veronica", the Hulkbuster armor, as a "[[GodzillaThreshold last resort]]" to stop the Hulk. So when it needs to be employed, it serves this function perfectly.

[[folder: Literature]]

[[folder: Live Action TV ]]

* In ''Series/TerminatorTheSarahConnorChronicles'', Cameron installs a bomb in her head and gives John the detonator, in case she ever becomes a threat to him. She has good reason to worry about this, because it's happened to her before and nobody (not even the Teminators themselves) knows what causes a reprogrammed Terminator to suddenly revert to its default programming.

** The Kents are also known to keep pieces of green kryptonite around. It was first used to counteract red kryptonite, but later his parents and [[SecretKeeper Chloe]] [[PlatonicLifePartners Sullivan]] uses it a lot to stop him whenever he is mind controlled (Chloe saves Lex from Clark in ''Hypnotic''), possessed (Jonathan saves Chloe from Dawn possessing Clark in ''Spirit'') or is otherwise not in his right mind (Chloe saves Jonathan from Clark when he is made paranoid by silver kryptonite in ''Splinter'').

[[folder: Video Games ]]

[[folder: Web Comics]]

[[folder: Web Original ]]

[[folder: Western Animation ]]
* ''WesternAnimation/SilverHawks'': Each of the SilverHawks has an emergency off-switch to be used if any of them went berserk for unforseen reasons.

[[folder: Real Life ]]

* In ''Film/AvengersAgeOfUltron'', Franchise/IronMan and Bruce Banner discuss on how they developed "Veronica", the Hulkbuster armor, as a "[[GodzillaThreshold last resort]]" to stop the Hulk. So when it needs to be employed, it serves this function perfectly.

* Some people have said that the second amendment of the American constitution, the right to bear arms, is there partly in case of the government being taken over by an oppressive tyrant of some kind. In this event the people would be able to overthrow the regime because they would all be equipped with guns. This can be seen as the founding fathers giving future generations of citizens a kryptonite ring. There is substantial disagreement over whether this was a true intention as well as just what the actual effectiveness of it is in the 21st Century given the now extremely broad gap between civilian and military weaponry.

* ''Series/TheFlash2014''
** Cisco creates the [[FreezeRay Cold Gun]] in case Barry turns out to be dangerous, like the other [[DifferentlyPoweredIndividual metahumans]]. Unfortunately, it gets stolen and later gets into the hands of the future Captain Cold. Both Wells and Barry tear Cisco a new one for making the gun.
** The reason why Season 5 ArcVillain Cicada became such TheDreaded among metahumans: he has a special dagger that saps all dark matter energy out of any metas in the vicinity, depowering them and becoming vulnerable to Cicada's attacks. Fortunately for the heroes, there's one meta on their side who's revealed not to have her powers derived from dark matter, so she is immune to the dagger's effects: Killer Frost. [[spoiler:This is also why HiddenAgendaVillain Eobard Thawne is actively helping the heroes fight Cicada (through his unknowing apprentice Nora, the Flash's daughter). The dagger is strapped to him in the future, leaving him powerless while he awaits death row.]]

[[caption-width-right:300:Nothing says true friendship than to give your buddy the only thing that can kill you. [[note]] But let's be honest, Franchise/{{Batman}} [[CrazyPrepared already had kryptonite.]] [[/note]] ]]

** ''ComicBook/InfiniteCrisis'' subverts this when Batman tries to use his Kryptonite ring on Superman of Earth-Two, which has no effect, as explained in explication.

** To a lesser extent, the ''Comicbook/{{Shazam}}!'' Captain Marvel is employed occasionally as the one superhero tough enough to take on a controlled Superman if necessary. Or rather, he's tough enough to stall Supes in a fistfight long enough to call his magical lightning enough times to knock out his Kryptonian foe[[note]]Most forms of magic are able to bypass Superman's NighInvulnerability and damage him just like a de-powered kryptonian. As for how the Kryptonite Ring trope comes into play: Superman isn't going to tell just anyone this fun little fact, but he can usually trust the goody-two-shoes Captain marvel[[/note]]. Altough, at least in [[ComicBook/KingdomCome one occasion]], it was ''Captain Marvel'' the brainwashed one, not Superman.

** Professor Xavier also had the "Xavier Protocols", a set of plans on how to stop the X-Men. Xavier himself is the subject of the first entry, which includes blueprints for a [[PowerNullifier telepathy-blocking battlesuit]]. However, these have rarely been mentioned since they were first introduced.

* Some people have said that the second amendment of the American constitution, the right to bear arms, is there partly in case of the government being taken over by an oppressive tyrant of some kind. In this event the people would be able to overthrow the regime because they would all be equipped with guns. This can be seen as the founding fathers giving future generations of citizens a kryptonite ring. There is substantial disagreement over whether this was a true intention as well as just what the actual effectiveness of it is in the 21st Century given the now extremely broad gap between civilian and military weaponry. [[Administrivia/RuleOfCautiousEditingJudgment Which is as much as should be said about the matter]].

** The reason why Season 5 ArcVillain Cicada became such TheDreaded among metahumans: he has a special dagger that emits a field that saps all dark matter energy out of any metas in the vicinity, depowering them and become vulnerable to Cicada's attacks. Fortunately for the heroes, there's one meta on their side who's revealed not to have her powers derived from dark matter, so she is immune to the dagger's effects: Killer Frost. [[spoiler:This is also why HiddenAgendaVillain Eobard Thawne is actively helping the heroes fight Cicada (through his unknowing apprentice Nora, the Flash's daughter). The dagger is strapped to him in the future, leaving him powerless while he awaits death row.]]

* ''Series/TheFlash2014'' Cisco creates the [[FreezeRay Cold Gun]] in case Barry turns out to be dangerous, like the other [[DifferentlyPoweredIndividual metahumans]]. Unfortunately, it gets stolen and later gets into the hands of the future Captain Cold. Both Wells and Barry tear Cisco a new one for making the gun.
** The reason why Season 5 ArcVillain Cicada became such TheDreaded among metahumans: he has a special dagger that emits a field that saps all dark matter energy out of any metas in the vicinity, depowering them and become vulnerable to Cicada's attacks. [[spoiler:This is also why HiddenAgendaVillain Eobard Thawne is actively helping the heroes fight Cicada (through his unknowing apprentice Nora, the Flash's daughter). The dagger is strapped to him in the future, leaving him powerless while he awaits death row.]]

* In ''Series/TheFlash2014'', [[TheSmartGuy Cisco]] creates the [[FreezeRay Cold Gun]] in case Barry turns out to be dangerous, like the other [[DifferentlyPoweredIndividual metahumans]]. Unfortunately, it gets stolen and later gets into the hands of the future Captain Cold. Both Wells and Barry tear Cisco a new one for making the gun.

* The second half of ''VideoGame/TheLegendOfZeldaPhantomHourglass'' involves Link trying to forge the Phantom Sword, the only weapon capable of destroying the otherwise-invulnerable Phantom enemies [[spoiler:as well as Bellum, the BigBad of the game.]]

* The [[Roleplay/GlobalGuardiansPBEMUniverse Global Guardians]] keep a locked file in their computer database called the Code Red Omega Scenario. It is a tactical plan to take down each and every member of the Guardians, if it ever became necessary to take them all down.

* {{Downplayed}} in ''Webcomic/ElGoonishShive''. When Sarah volunteers to be Tedd's lab assistant, Tedd feels that [[http://egscomics.com/comic/2012-04-16 if they are to work together]], he needs to make up for the [[NoodleIncident catgirl incident]]. So, as a show of trust, he [[http://egscomics.com/comic/2012-04-23 gives her a watch]] that can let her shapeshift into a clone of Tedd. While he doesn't particularly mind her [[CheckingOutTheNewBody taking a peek]], he points out that there are still all sorts of ways Sarah could use Tedd's form to embarrass or humiliate him if he ever steps over the line again.

** From the ComicBook/LegionOfSuperHeroes example above: General Zod's son, Drax, stole Brainiac 5's kryptonite and tries to use it on Supes, but Superman kicked him through a conveniently placed PhantomZone portal, ''before he could even open the lead container''.