A Forgotten Superweapon is any device that the person or crew [[ItWasWithYouAllAlong had with them the whole time]], but they had forgotten that they had. Usually in vampire shows, it's a cross or handy bottle of holy water that was handed to the superhero(ine) [[ChekhovsGun early in the show]] and which she and the audience had long since forgotten until the flash of inspiration hits.

This trope should not be confused with LostSuperweapon, where said weapon has been ignored due to the passage of time and/or its keepers (and is always literally a superweapon and not just any device). In contrast, a Forgotten Superweapon will actually be around but forgotten, because the characters [[IdiotBall have been distracted]] or the writers hadn't [[AssPull come up with it]] yet. Compare NuclearOption, where everyone remembers that they have the superweapon, they just really don't want to use it.

If the object in question gets used early in the series and then isn't used ''at all'' later, it's ForgottenPhlebotinum. See also ChekhovsBoomerang and ChekhovsGun. Compare ForgotAboutHisPowers.

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!!Examples:
[[foldercontrol]]

[[folder:Anime & Manga]]
* ''Anime/MazingerZ'': In episode 10 Mazinger-Z shot missiles from its fingers. That weapon never showed up again. It is somewhat subverted, though, since it was not so useful and Mazinger-Z had better and more powerful weapons, so it is likelier than the animators realized it was silly placing missiles in the fingers of a RocketPunch, and they chose to forget about it and replace them with weapons were not AwesomeButImpractical.
* ''Anime/UchuuSenkanYamato'' involved a ship full of idiots who seemed to forget they had the WaveMotionGun until the end of each episode. Truly, a show built upon the Forgotten Superweapon. However, this could be {{handwave}}d away with the explanation that the ship was almost completely defenseless for several minutes after firing the Wave Motion Gun -- it used so much power they had to wait until the engines came back online.
** More importantly, the ship is defenseless for several minutes ''before'' firing the gun, and completely dependent on its tiny fighter planes to defend it while it preps the gun. If they can just fire the thing without being prevented from doing so, that is usually the end of the fight. Another shortcoming of the WaveMotionGun is that it ''is'' the mother of all {{BFG}}'s, capable of vaporizing a ''continent'' when used at full power, and not every battle warrants that kind of destruction. The first time they used the gun, without entirely knowing what to expect, they accidentally caused a titanic amount of collateral damage and almost fell into the resultant explosion themselves. Later, on Pluto, Captain Avatar vetoes using it on the Gamilon base because it would have wiped out Pluto's primitive native animal life, which he felt they had no right to do.
** Plus not every enemy could be defeated by the application of the Wave Motion Gun (The Comet Empire citadel) and not every enemy was stupid enough to sit there waiting for the Wave Motion Gun to charge (Desslok blocking the muzzle of the gun with space mines, so the Yamato would blow up if it fired). Powerful, yes. The solution to every problem the Star Force faced? No.
* ''Anime/{{Macross}}'':
** Justified in ''Anime/SuperDimensionFortressMacross''; the SDF-1's Macross cannon is only fired on a handful of the occasions that clearly called for it. But this was because the weapon was highly unreliable, with technology the crew barely understood in the first place. And that when the fold engine had vanished in the third episode, it took with it the power conduits needed to make the gun work properly in its original configuration, forcing a transformation sequence that initially threatened to wipe out the city inside the ship! Fortunately, the engineers later rebuilt the city with the transformation in mind and developed better shelter protocols.
** Of course, by the end of ''Anime/{{Macross 7}}'', Macross cannon technology has been developed to the point where it can now be [[BeamSpam beamspammed]].
* ''Anime/TheBigO'''s Final Stage attack is a chest-mounted cannon that not only blows through an entire city, but required nearly the entire series worth of hints and flashbacks to lead up to its firing. Amusingly, [[spoiler:it turns out that pilot Roger Smith's aim is a little off and BigBad Alex Rosewater's robot is only ''half'' vaporized]]. Pity the series ended with that episode, else he could have worked on that aim (well if the gun hadn't completely turn to scrap after one use, but he might've been able to fix it).
** The big plot element of ''The Big O'' was that ''everybody'' had ''amnesia''. So a "forgotten" ''anything'' is a trifle redundant.
*** Not to mention that [[spoiler:said WaveMotionGun also completely disabled Big O after being fired]].
*** Thankfully, in the ''VideoGame/SuperRobotWars'' games, it worked just fine.
* In ''Anime/DragonballZ'', when Goku decides to use the Spirit Bomb at the end of the Buu saga, he admits that he forgot about it. But there's a few good reasons for that:
** First, he hadn't used it in ten years.
** Second, both times he used it, it ''didn't work''. Vegeta was hurt enough to drive him off, but survived (which [[HeelFaceTurn worked out]], but whatever), while Freeza survived without too much damage. It ''did'' defeat four movie villains, but the canon status of the movies is uncertain.
** Third, it takes a long time to charge, meaning that the strongest fighter has to sit out while the others -- [[CantCatchUp who aren't nearly as strong]] -- hold off the villain for as long as it takes.
** Finally, it can't be done in [[NextTierPowerUp Super Saiyan form]], as the transformations "fill his heart with hate," and Goku needs as pure a heart as possible to make it work.
* The title Gundam in AlternateUniverse series ''[[Anime/AfterWarGundamX Gundam X]]'' packs the Satellite Cannon, a weapon powerful enough to take out large chunks of the landscape in a single blast. However, it's not forgotten so much as unusable much of the time, since it requires a full moon to power it (the microwave power station has to be in line of sight with the GX to beam the energy down to Earth). In addition, [[AwesomeButImpractical using the Satellite Cannon requires the Gundam X to stand still for several seconds, leaving it defenseless until it finishes charging up.]] The heroes acknowledge these problems and eventually work out an alternative to the Satellite Cannon.
** That is, until an upgraded version of the superweapon is provided later in the series, and does not have the apparently most story significant restriction of using the weapon.
** Then again, an important theme of Gundam X was that the weapon ''shouldn't'' be used, showing Garrod reluctant to fire it because of the wholesale slaughter it brings.
** There's also the fact that the Gundam X's Satellite Cannon was actually destroyed in the first battle against Carris. Nobody outright says "the cannon was destroyed", but you can clearly see the cannon and the [[BuffySpeak power....gathering....thingies]] get smashed to pieces when Carris's Vertigo disables the Gundam. The reason they stopped using the Satellite Cannon until they got ahold of the Double X was because they didn't have it anymore. It's also why the "Divider" equipment was made and installed on the Gundam; it was less an "alternative" to the Satellite Cannon so much as it was a replacement because the Gundam needed new weapons.
* In ''Manga/{{Trigun}}'', during the final battle between Vash and Knives, Vash is almost defeated, until he remembers the literal "forgotten weapon" of the Cross Punisher, which he brought with him, but then never used until the last moment.
* Both averted and played straight in many of Go Nagai's ''SuperRobot'' series. One of the best examples was [[Manga/GetterRobo Shin Getter Robo]], in which the heroes really have no objection to cutting the opponent to pieces with whatever reliable weapon they have out at the time. However, when it comes time to fight [[EvilKnockoff Metal Beast Getter G]] it takes the previously-unmentioned Stoner Sunshine to win the fight.
* In ''Manga/YuYuHakusho'', Kuwabara, Yusuke, and the masked fighter fight with three [[{{Brainwashed}} mind-controlled]] humans for three episodes wrestling with the dilemma of having to kill/harm humans the entire time (they had previously only killed demons). In the end the masked fighter uses a move which removes the [[{{Brainwashed}} mind-control]] and leaves everyone unharmed. It turned out to be intentional. The Masked Fighter realized that Yusuke needed to "grow up" to be able to fight Toguro. Only after Yusuke finally was willing to deliver a killing blow did The Masked Fighter use that technique. Something similar happens later in the series when Yusuke fights the Doctor.
* ''Manga/OutlawStar'' gives us the Caster Gun, a gun that literally spews magical spells with each shell fired, and is also extremely effective against most users of the common-as-crabgrass Tao Magic. However, this is {{handwaved}} away by the guns themselves being increasingly rare and ammo being just as rare in itself (to the point that some types of shells have vanished completely - and no one is making new shells [[spoiler:until the fanservice episode, but that's another story]] at all).
* Justified in ''Anime/ScienceNinjaTeamGatchaman''. In this series, the team's ship has the all powerful Fiery Phoenix effect to destroy seemingly any opponent. However, the effect is so taxing and potentially dangerous to the team when it is engaged that they need a ''good'' reason to use it, and it uses a ''lot'' of fuel. So, the effect is only used in comparatively few episodes.
** It ''fails'' to defeat two Galactor mecha during their first round, and the first defeat almost gets the team killed as a result.
** In one episode where they have to use it twice, it all but empties the tanks.
* Used in ''WebVideo/YuGiOhTheAbridgedSeries'' where Yugi forgets he can summon Slifer the Executive Producer until Bakura mentions it.
* ''Anime/ElHazardTheMagnificentWorld'' had everyone living under the Eye of God, an ancient super weapon in atmosphere level orbit that's creation was lost to legend and its operations steeped in mysticism and tradition, the damn thing had to be unlocked by three priestesses and operated by two princess.
** It also has Ifurita, one of the cutest forgotten super weapons in this trope. Compact, devastating and wound up by key.
* ''Literature/TheThirdTheGirlWithTheBlueEye'' has Gravestone, who/which was presumed destroyed long ago but turned out to be fully operational and both ready and willing to fulfill its purpose.
* ''Anime/{{Voltron}}'' had the Blazing Sword. It killed pretty much everything in a single hit and was more effective than Voltron's other weapons, and in the first episodes it was even used early in a fight. There is very little reason for the crew to not be slicing up Robeasts right off!
[[/folder]]

[[folder:Comic Books]]
* The Magnificence, an ancient artifact introduced during Simon Furman's run on the IDW ''[[ComicBook/TheTransformersIDW Transformers]]'' comics. The relic could literally answer any question with [[StoryBreakerPower perfect accuracy]]. It disappears and is never mentioned again in [[ComicBook/TheTransformersAllHailMegatron subsequent stories]].
** It returns in [[ComicBook/TransformersMoreThanMeetsTheEye Lost Light]] where we learn where it’s been, the artifact’s origins, and now has limiting conditions on how it doles out knowledge.
[[/folder]]

[[folder:Films -- Live-Action]]
* ''Film/DudeWheresMyCar'' plays with this trope and divides it. The superweapon, the [[spoiler:Continuum Transfunctioner]], is actually the problem and needs to be turned off, yet the buttons are too small. It's solved with the previously-acquired [[spoiler:bendy straw.]]
* In ''Film/TheMatrix'', an EMP blast wipes out sentinel robots, and doesn't even harm the humans in the blast radius. However, this is actually an aversion. While the EMP blast does wipe out Sentinels, it also disables any ship that uses it, so it is absolutely a last resort. This is shown demonstrated in the third film, when the use it to wipe out the army attacking Zion, but also destroy all of Zion's remaining defenses just in time for the second wave of the invading army to arrive.
* ''Film/PacificRim'' has the Jaeger mecha Gypsy Danger's sword, which was conveniently forgotten about in favor of punching the giant Kaiju monsters until one flew away with the mecha in its claws. Even more odd when you consider that the Jaeger's two pilots were mind-linked, yet somehow only one of them knew about the sword.
** It's repeatedly stated that Kaiju blood is horribly toxic ([[spoiler:Hannibal Chau's stunt in TheStinger]] notwithstanding) so it's possible that the sword is locked until the Jaeger is a fair distance away from populated areas.
[[/folder]]

[[folder:Literature]]
* Perhaps the most egregious example is the Flaz Gaz Heat Ray, as discussed in Nick Lowe's essay, ''[[http://news.ansible.co.uk/plotdev.html The Well-Tempered Plot Device]]'':
-->''"Everyone knows, I imagine, the story of the Flaz Gaz Heat Ray, perhaps the most outrageous DeusExMachina ending in all literature. There the heroes were, stranded deep in an enemy sector of space, surrounded by an entire enemy fleet with the guns trained on them, when the maestro realized all of a sudden he had only one page left to finish the book. Quick as a flash, the captain barks out: "It's no use, men. We'll have to use the Flaz Gaz Heat Ray." "Not -- not the Flaz Gaz Heat Ray!" So they open up this cupboard, and there's this weapon that just blasts the entire fleet into interstellar dust. One almighty zap and the thousand remaining loose ends are quietly incinerated."''
:: [[DownplayedTrope Note, though]], that the above paragraph is not an accurate summary of events in [[https://www.peltorro.com/Badger_SF089.pdf the actual book]], where the Heat Ray is one of a number of weapons tested against the enemy, and though it forces them into a temporary retreat it certainly does not destroy them. ([[ArsonMurderAndJaywalking Oh, and it's spelt 'Flazgaz']]).
* ''Literature/HarryPotterAndTheOrderOfThePhoenix'': Sirius Black gives Harry a magic mirror in case Harry needs to contact him. Many months/chapters later, Harry really needs to contact Sirius, but doesn't use the mirror. Justified on Harry's end, as he was not only initially determined to not use the mirror for personal reasons, he actually ''did'' forget about the mirror in the intervening time due to the rest of the plot grabbing his attention. Still doesn't explain why ''Sirius'' didn't suggest using it instead of the risky method of sneaking into fireplaces.
* From the ''Literature/{{Belgariad}}'', the Orb of Aldur is a small stone with literally earth-shattering power. Main protagonist Garion gets his hands on it in the fourth book, and has absolute control over it thereafter, but only uses it directly a couple of times out of many, many dire straights. Why? Because he's too modest, apparently. It's hinted that succumbing to pride and coveting the Orb too much is what lead to the decline of the first BigBad, and that the same might happen to Garion should he use it to solve all his problems.
* In ''Literature/InheritanceCycle'' after his battle with [[spoiler: Murtaugh]] Eragon remembers that he has [[spoiler: Brom's ring]] which, had he used it, would have let him win easily.
[[/folder]]

[[folder:Live-Action TV]]
* ''Series/BuffyTheVampireSlayer'':
** [[OlafsHammer Olaf's Troll hammer]] "[[Recap/BuffyTheVampireSlayerS5E11Triangle Triangle]]". The weapon was obtained roughly halfway through the season, and not used through any of the its numerous crises until they pulled it out in "[[Recap/BuffyTheVampireSlayerS5E22TheGift The Gift]]" -- where it was shown to be so powerful it could knock around a god (this despite it merely knocking out Xander in its previous appearance). After Buffy beats Glory into submission and abandons the hammer at a badly-injured Ben's side, it's never used or even mentioned again, save in a flashback to Anya's past in season 7. Possibly justified in that even Spike's vampire strength couldn't lift it (as seen in "Blood Ties"); only Buffy could actually do so.
** The Dagon Sphere showed up even earlier in the season, but despite knowing that it was designed to repel Glory, nobody actually used it against her until the finale.
** And there was that rocket launcher from "[[Recap/BuffyTheVampireSlayerS2E14Innocence Innocence]]". It's mentioned again in "[[Recap/BuffyTheVampireSlayerS3E22GraduationDayPart2 Graduation Day Part 2]]" when Xander thinks Buffy intends to use it against the mayor, only to be told it wouldn't be powerful enough. After this it's only seen once, in season 7's ""[[Recap/BuffyTheVampireSlayerS7E6Him Him]]", and even then only as a FunnyBackgroundEvent -- Buffy attempts to use it against Principal Wood while under the love spell carried by R. J. Brooks' letterman jacket (fortunately, she's stopped in time). To be fair, it's clearly [[AwesomeButImpractical far too powerful to take along on random patrols]], and too dangerous to use against Adam due to his nuclear core, though it might have been useful in slowing down [[PhysicalGod Glory]].
* ''Series/MightyMorphinPowerRangers'': At the start of season 2, the heroes get a [[SoLastSeason new set]] of (supposedly much more powerful) HumongousMecha to face their new BigBad. Their mentor explains that he had been in possession of these mecha the entire time but was saving them for when the Rangers ''really'' needed them. It occasionally is indicated that they are not supposed to "escalate" the violence, so they aren't supposed to use any weapons or Zords until they need them. That said, once they got a new one, the series was usually pretty good at bringing them back.
* ''Franchise/{{Stargate|Verse}}'': The franchise lives on this trope. Now the superweapons, plebowhatsits, and other toys may not exactly be forgotten, but they tend to be built by the Ancients, are occasionally buried, and are usually good for at least one moment of glory. The Ancient outpost in Antarctica springs to mind as an example.
** ''Stargate'' does avoid most of these by introducing inherent flaws or one-time uses into a lot of alien technology. Specifically the Ancient weapon in Antarctica (as well as the chair on Atlantis) was brought up and discarded a few times due to the lack of [=ZPMs=] to power it and its limited ammunition, with the issue finally getting resolved by the Antarctica chair's destruction in the series finale of ''Atlantis''.
** In an interesting subversion, the imminent Wraith attack on Earth did motivate the higher-ups to recall Atlantis back home, even though for a moment it looked like as if they're going to play this trope straight by having the ship unexpectedly break down at the edge of the Milky Way. Fortunately, Zelenka {{Ass Pull}}ed the [[EleventhHourSuperpower wormhole drive]] out of nowhere.[[note]]The series finale was originally written to be a cliffhanger season finale, and Atlantis was supposed to be stuck between galaxies till the 6th season premier. Fortunately word of no 6th season came early enough in post production that the writers were able to literally AssPull the wormhole drive and tack on a conclusion to avoid the series ending on a cliffhanger.[[/note]]
* On ''Series/{{Heroes}}'', the writers seem to have finally realized that Sylar's power to "understand how things work" is good for more than just stealing peoples' brains. Apparently, it can also be used to understand the show's plot.
** The writers also forget all of Sylar's acquired secondary powers until convenient.
** One of the worst cases was where Sylar decides to go on a mission to investigate if Arthur is really his father. Now, the simple solution would be to use his super brain to realize that people in the real world have this thing called a "paternity test." Also, everyone's DNA on the show is already on the national database, because that's how Mohinder found them, making this rather straight forward. Instead, he decides to go on a mad hunt for more super powers, in the hopes that he will find one that will give him the answers he needs. By sheer coincidence, the next lady he finds reveals that she's a living polygraph. Mystery solved.
** The same goes for Peter, back when he still had more than one. Hell, the second [[strike:season]] volume could be named this as Peter never uses any of his powers after dropping his amnesia, except as the plot demands.
** Claire/Adam both have Jesus blood, which is so powerful can bring people back from the dead who've lost large chunks of their brains. Apparently the writers never considered the ramifications for such a device, and conveniently ignored it later on.
** Molly has the power to locate anyone on Earth. Molly sees Sylar as the boogie man, because he murdered her parents. At the end of season 1, Sylar disappears from the scene with a trail of blood leading to a sewer. Yet she never once thinks to use her powers through season two to confirm that he's really dead.
*** This is especially maddening at the end of season two, when Sylar kidnaps Molly only to be rescued by Elle. Sylar narrowly escapes, and no one thinks to use Molly in order to chase after him.
*** This continues even into the alternate volume three, which can be seen on the DVD. Elle is still on the trail of Sylar, who is accumulating more and more powers. Again, despite the fact that Molly has the power to track Sylar down.
* ''Series/StarTrekTheNextGeneration'' had an interesting twist on this with a Forgotten Vulcan Superweapon that amplified its user's telepathic powers until it could effortlessly destroy any foe. Picard and Riker wind up attempting to keep it from being re-assembled. [[spoiler: Eventually it's rebuilt, but it turns out to be basically useless against enemies who have no hateful thoughts. The device was used when Vulcans were still emotional and war-like and the device used those thoughts against them. Once Vulcans embraced logic and peace, the weapon was harmless, so it wound up being forgotten because it had been rendered useless.]]
* One episode of ''Series/TheUnit'' had Alpha Team trying to disable a bomb which will set off nuclear material in a train. The bomb is under an overpass on which the train is traveling. However, the team forgets that they have "national security" command over the ''entire infrastructure of America'', so the train conductor isn't told to stop the train until it's almost too late.
* ''Series/{{Supernatural}}'' introduces a handgun, forged by Samuel Colt himself in 1835 that has the ability to kill any demon with one shot. Originally, The Colt was limited by the number of bullets it can fire, but [[MrFixit Bobby Singer]] (with some help from [[NobleDemon Ruby]]) forged new bullets, thus solving that problem. Sadly it then gets stolen by Bela, depriving them of it. And after an [[BrokeYourArmPunchingOutCthulhu altercation]] with [[spoiler: Lucifer]], it appears to be lost (it is never confirmed that it was left behind, but they don't use it again and the villains have it later).
** It was later brought back to kill a phoenix but then got lost in a time loop. It finally returns in Season 12 and gets used [[spoiler:but is then outright destroyed, preventing it from ever being used again]].
** This is also averted with Ruby's knife, which can kill (as opposed to exorcise) demons. They still have it, and regularly use it.
* ''Series/SpiderManJapan'' has a similar thing to ''Anime/{{Voltron}}'' with Leopardon. {{Lampshaded}} in ''Comicbook/SpiderGeddon'', where Takuya is absolutely astounded when Otto Octavius suggests that if he used [[ThrowingYourSwordAlwaysWorks Sword Vigor]] ''first'', his battles would be over much sooner.
[[/folder]]

[[folder:Video Games]]
* In ''VideoGame/MetalGearSolid,'' the small card that you've been carrying around the entire game without really knowing the purpose of is the only way to activate the HumongousMecha without the password.
** [[spoiler: Rex from the first ''VideoGame/MetalGearSolid'']] appears to have become this by the time ''VideoGame/MetalGearSolid4GunsOfThePatriots'' happens.
* At the end of ''VideoGame/ZorkGrandInquisitor'', Dalboz mentions that now would be a good time to use a spell that came with your spellbook and hasn't been used yet in the game. Casting the spell restores magic to the land and ends the game.
** In a way a literal inversion, as the spell was written in the book backwards and needed to be magically turned around in order for it to work properly.
* Shiki's battling against Nanaya, his [[EnemyWithout manifested nightmare of becoming a murderer]], in ''[[VisualNovel/{{Tsukihime}} Kagetsu Tohya]]'' never goes well, since Nanaya Shiki is simply a much better fighter than Tohno Shiki. It takes a while for Shiki to remember his one advantage: Nanaya doesn't have [[MagicalEyes Mystic Eyes of Death Perception]]. [[spoiler:Of course, by the time Shiki remembers, Nanaya's death makes the point moot]]. He then proceeds to forget his eyes ''again'' until halfway through his fight with [[spoiler:Kishima Kouma]].
* In ''VideoGame/SuperRobotWarsAdvance'', the OriginalGeneration Super Robots' final attacks can be explained away as Axel or Lamia taking that long of a time to figure out that they could overclock their rides that way. It takes a bit of research and analyzing schematics to realize that the Ash Saviour's extra armor plates are actually AttackDrone pairs. However, there is no excuse for not figuring out early on that that big, folded-up cylinder mounted on the Laz Angriff is anything but a really big cannon.
* A silo full of these is one way to resolve the plot of the ''Metro 2033'' series, both [[Literature/{{Metro 2033}} the book]] and [[VideoGame/{{Metro 2033}} the game]]. Granted, they've only been forgotten for about 20 years, but when surviving a postapocalyptic wasteland becomes your primary concern, nuclear missiles tend to fade into the background. On top of this, very few people who could actually ''use'' the missiles were left alive.
* In ''VideoGame/BatenKaitosOrigins'', the PowerTrio finds out that [[spoiler:they've been walking around with a superweapon in their party; Guillo, Sagi's magical sidekick, is the puppet that the Children of the Earth used to kill Malpercio, and while it's not as powerful as it was then, it's still a formidable fighter]].
[[/folder]]

[[folder:Webcomics]]
* ''Webcomic/BobAndGeorge'': [[http://www.bobandgeorge.com/archives/020722 Bob reminds George, after rescuing him, that he could have used his superpowers to escape. George blows up the fortress]]
** [[http://www.bobandgeorge.com/archives/030720 Tweaked, here]]. (Answer: it broke.)
* ''Webcomic/SchlockMercenary'' has "Discontiguous Particle Acceleration System". As the team's {{pyromaniac}} figured out, a weapon that "was built before teraports and too big for wormgates [...] not sharing the system with anything worth attacking or defending" ''should'' be a "Hyperspace DeathRay". It wasn't used on account of [[spoiler:a colony of hippies settled inside its "barrel"]]. Tagon's Toughs accidentally prevented an attempt to reclaim it by the proper owner's successors, then the new owner (who knew what it is and who he deals with) quickly moved [[spoiler:the colony to a safer environment]] and the gun to "undisclosed location" as soon as possible, after which let Toughs witness the test firing as a bonus. This becomes a major plot point later on; things like the Long Gun and Teraports have been known to the Gatekeepers for hundreds of thousands of years (and many levels of RecursivePrecursors before them), but they supressed the technology and even refused to use it themselves.
[[/folder]]

[[folder:Western Animation]]
* Combat in ''WesternAnimation/MegasXLR'' is built around the Forgotten Superweapon, with many of the trump cards apparently winking into existence as needed, never to be seen again after their use. The pinnacle of the lot is a weapon that causes the title robot's hands to burst into flames, activated with a button marked "Five Minutes 'Til End Of Episode." The one in "Dude, Where's My Head?" even had the computer raise its eyebrow.
** Subverted by the "Voltron Sword Thing", which was first a combo move, then became a button.
* ''WesternAnimation/AdventuresOfTheGalaxyRangers'' had the Scarecrow, a living weapon buried and dormant for centuries, until a new farming colony is built on the old battle site. Terror ensues.
* ''Franchise/{{Transformers}}'':
** ''WesternAnimation/TransformersAnimated'' has [[spoiler:Omega Supreme]], who could have been used as soon as they had some [=AllSpark=] fragments. Granted, the series is a mild aversion of NoEndorHolocaust, so they probably just didn't want to escalate a battle if they could help it, but that doesn't explain why they didn't at least bring him back online. Ratchet’s own misgivings about reviving his friend as a doomsday weapon may have also come into play.
** The Dark Star Saber of ''WesternAnimation/TransformersPrime'' falls into this until the very end of season 3.
* The Great Gummiscope in ''WesternAnimation/AdventuresOfTheGummiBears.''
* ''Anime/{{Voltron}}'' never formed Blazing Sword until after the Ro-Beast and Voltron had stomped half the countryside flat and Voltron was getting its ass handed to it on a big Roboplatter. However, this was for a very good reason: Voltron could not defend itself while wielding the sword, so it had to fight until the robeast was incapacitated or gave them an opening. In an early episode, Voltron Force faces a new Juggernaut robeast built by King Zarcon, not Haggatha's sorcery. They come out with Blazing Sword already formed, but get roundly trounced. For three days, the Royal Army holds off the monster while Voltron trains, and in a huge battle, the individual Lions beat down the robeast until it can't fight back, then form Voltron, blast it a few more times for good measure, Form Blazing Sword, and dispatch it.
** This was parodied in an episode of ''WesternAnimation/RobotChicken'' where it went through a dance contest against a Ro-Beast and lost, but then just used the sword while it was laughing at their defeat.
---> '''Newsreader:''' ...and in other news tonight, Voltron got totally served.
* A glaring example in the season three premiere of ''WesternAnimation/MyLittlePonyFriendshipIsMagic''. Since the ponies are going to a cursed kingdom that has been besieged by a pure evil [[LivingShadow embodiment of darkness]], you'd think they would have taken the [[MacGuffin Elements Of Harmony]] along for the ride. It's justified for the main cast since they didn't know about said monster until they arrived, but Princess Celestia certainly did. Why she didn't give the the elements, or even ''warn them'', is anyone's guess.
** The most likely reason is that she knew the elements would fail to win a lasting victory since that was how she beat him last time. What they really needed is an unrelated LostSuperweapon, and whether Twilight would figure this out and organize her team to accomplish it was a SecretTestOfCharacter.
[[/folder]]

[[folder:Real Life]]
* The [[https://en.wikipedia.org/wiki/Iowa-class_battleship Iowa Class Battleships]] served with the US Navy from World War 2 up through the 1990's. All four have since been converted into museum ships, but as part of the donation agreement each museum must maintain the ships to a certain standard so that they might be again returned to service in case of "national emergency". Thus the ships have become superweapons HidingInPlainSight as ''superweapon museums'' with most patrons completely unaware that they could, in theory, be reactivated.
** The Navy also maintains [[SecretGovernmentWarehouse its stock]] of spare 16" gun barrels and thousands of rounds of ammunition in case of such an eventuality.
[[/folder]]
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