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->''"Anytime a hero is somehow outpowered and/or outclassed by the villain, he will invariably release powers/new moves he never knew he could accomplish... but his old teacher did!"''
-->-- '''[[http://www.cs.utah.edu/~duongsaa/more_htm/jk_100animeRules.htm The 100 Rules of Anime]]''': ''#84 The Law of Dormant Powers''

Some superhero comics authors seem to get bored of the same old powers. They add new ones to the same characters whenever they feel that a new power would open up a new story, or a new danger needs a new response, or what the hell, whenever they feel like it.

Sometimes a {{retcon}}, a power upgrade or some bit of {{Phlebotinum}} is employed to explain the new power, but often the character just does something they've never done before and when their friends say, "I didn't know you could do that!", they come back with either "I've never needed to, till now," or worse, "Neither did I!"

Generally speaking, this trope is far more forgivable earlier in the story- with a character who has only recently been empowered and is fully {{justified|Trope}} in [[HowDoIShotWeb not knowing what he can do]]. Likewise, "neither did I until now" in an experienced character can be reasonable, if it's happening in some circumstance or special condition that the character has never encountered before.

However, this is sometimes employed as a form of DeusExMachina - having written themselves into a corner with a villain or situation that's [[OnlyTheAuthorCanSaveThemNow too overwhelming for our heroes to handle]] with the tools they've been given, the writer decides to have the hero instantaneously learn the one ability he needs to save the day or bring a character BackFromTheDead. Frequently, without any form of {{Foreshadowing}} to suggest that he or she can do that. It gets worse if they conveniently forget this ability when it would come in handy in a later situation. This is often the case with a MarySue[=/=]MartyStu.

If the plot was crafted to fit the powers (as opposed to the powers changing to meet the needs of the plot) you have a PlotTailoredToTheParty or [[ThisLooksLikeAJobForAquaman a job for Aquaman]]. See also AdaptiveAbility, where your power is the acquisition of new powers/immunities. When the new ability is something overly narrow or silly, this often leads to FlightStrengthHeart, as was common in UsefulNotes/TheSilverAgeOfComicBooks. SuddenlyAlwaysKnewThat is the same type of retcon as this, but instead of "Neither did I", the character will explain that YouDidntAsk.

An inherent power of {{Science Hero}}es -- they're ''supposed'' to be building bizarre devices to deal with bizarre circumstances. It only gets annoying if the writer can't come up with a reason the guy would have that precise device on his person at that precise moment -- other than him just being [[CrazyPrepared crazy]]. Characters with a MorphWeapon or SwissArmySuperpower justify this by being able adjust their attacks, potentially coming up with new ways to use their existing powers.

Not all {{New Super Power}}s fall into this category; for example, a character undergoing TrainingFromHell to [[TimeToUnlockMoreTruePotential Unlock More True Potential]] is not NewPowersAsThePlotDemands.

Compare EleventhHourSuperpower, ImaginationBasedSuperpower, MagicAIsMagicA, SoLastSeason, and finally StrongAsTheyNeedToBe. Contrast with TheWorfEffect, where the plot demands the character's powers and abilities are suddenly rendered impotent.



[[folder:Anime & Manga]]
* In ''Manga/{{Naruto}}'':
** Members of the Uchiha clan frequently gets new abilities straight out of nowhere. Generally [[ComboPlatterPowers their powers]], tie into the eyes in some fashion (copying moves, mild precognition, trapping someone in an illusion by looking at them, shooting black fire from the user's eyes, hypnotic abilities), but as the story progressed, members of the Uchiha clan began to show more and more powers don't have anything to do with that, with many of them coming out of nowhere.
*** In the first example, we have Itachi Uchiha who in his battle against Sasuke showed such ability as [[InstantArmor Susanoo]] which in principle is some sort of giant spirit robot which wields 2 of Japan's Sacred Treasures: the Totsuka Sword (Evidently another version of the Kusanagi) which here is a LaserBlade with sealing abilities, and the Yata Mirror which functions as a shield able to protect against anything. All this appeared directly out of nowhere and needed only in order to seal Orochimaru and give Sasuke in the future the same ability. And also later in the battle with Kabuto, Itachi will show such jutsu as Izanami, the purpose of which is incredibly contrived and wouldn't have worked on anyone except than the person Itachi was fighting at the time.
*** In the following example Sasuke Uchiha when he attacks Orochimaru, deciding he's not useful anymore. Orochimaru tries to use his GrandTheftMe on Sasuke, only for Sasuke somehow to turn it back on him without explaning how did he do it. And later his Hawk Summoning Contract, which he didn't have at the time he left Konoha, and is unlikely to have obtained from Orochimaru.
*** But the biggest example this trope, in the series is an [[spoiler:Madara Uchiha. Since his resurrection, he just kept on revealing one new ability after the other to NoSell everything they threw at him. Pitched to collide against a Rasen Shuriken? Activate the Rinnegan! Outnumbered five to one? Summon clones and have them use Susanoo! Faced with a barrage of elemental and disintegrating attacks? Summon a mountain busting Susanoo! The guy who summoned you got defeated? Break your contract and fight on with unlimited chakra! Once he is revived and no longer immortal, he retains somehow the ability to absorb chakra through his Senju cells and goes on to steal Hashirama's Senjutsu-enhanced HealingFactor. When he is crushed under a pyramid of sand enhanced by Shukaku he simply bursts out with Susanoo despite having no eyes! Getting crushed by nine Bijuu tail whips and losing an arm? Have White Zetsu return your right Rinnegan and give his own arm as a replacement! You're the one against nine Tailed Beasts? Suddenly appears ability Limbo which was created solely to catch the Tailed Beasts off guard so that Madara can easily defeat and seal them! [[SerialEscalation And the list goes on...]]]]
*** And in the last example [[spoiler:Obito Uchiha]] apparently following the general tradition his clan, showed a new ability out of nowhere. [[spoiler:After his death he reverts to his younger self and immediately uses his shiny new Mangekyo Sharingans to teleport back to the world of the living, where he using chakra transfer transfers his eyes to Kakashi, stronger than they ever were when Obito was alive.]]
** This has extended to Sasuke's allies. Karin and Jugo reveal miraculous healing powers when Sasuke is wounded after their battle with Killer Bee, though they did not use these abilities when Sasuke was bedridden from injuries after fighting with Deidara. Karin also gains the ability to use chains capable of restraining a giant wooden statue when absolutely no other ninja is capable of doing so during the war arc, and is handwaved as it being because she's an Uzumaki.
** In order to get all the five kages to fight [[spoiler:a revived Uchiha Madara]], we learned Genma's team are able to use a watered down version of Tobirama's Hiraishin ("Flying Thunder God") technique and they quickly use it to transport the Raikage.
*** And apparently Minato didn't invent the Hiraishin, but the Second Hokage Senju Tobirama did, which has never once been hinted at.
** [[FauxActionGirl Sakura]] revealed during the war arc that she learned Tsunade's [[SuperStrength Souzou Saisei]] three years ago and has been charging it this entire time. This despite the fact she'd recently lamented how incredibly weak she was, as little as a few days ago within the story itself. Not to mention that she stopped using it and hung back watching the fight almost immediately afterward.
** Minato has apparently learned Sage mode AND get the Kyuubi cloak, two abilities he's not only never been hinted at having, but he only gained the Kyuubi chakra moments before his death.
* ''Manga/JoJosBizarreAdventure'' has two especially egregious examples of this trope, each used to finish off the BigBad of a story arc. The first example occurs in Part 3: the villain Dio Brando is virtually unstoppable because his Stand [[spoiler:has the ability to stop time]], so how do the heroes stop him? [[spoiler:Jotaro Kujo's Stand suddenly gains the power to stop time, which also lets him move in Dio's time stop, despite the fact that its only powers so far were SuperStrength and SuperSpeed]]. Of course, this is explained [[spoiler:by saying that Jotaro's stand has always had a smaller version of Dio's time stop power, and what had been seen as a Super Speed attack (his trademark "''ORA ORA!''") was actually him stopping time and then punching his foes' faces repeatedly (Jotaro never realized himself what was really happening, because he managed to stop time just briefly, and so it all happened very quickly before time went back to its regular flowing.]]
** Less prominent examples happen throughout part 3, mostly because [[EarlyInstallmentWeirdness Stands were a new concept, and didn't have such defined rules as they did in later parts.]] Some examples: [[spoiler: Star Platinum being able to stretch its finger with bullet-like force, Star Platinum being able to inhale like a vacuum, [[FantasticVoyagePlot Kakyoin's and Polnareff's stands being able to shrink to insect size,]] and Avdol's stand being able to create a flame that can somehow "detect life," a la the Human Torch example below. ]] None of these abilities are ever used more than once.
** Oh, it happens to the villains too. In Part 4, [[spoiler:Yoshikage Kira gets an ability he calls "Bites the Dust," which he gains after killing a character threatening to expose him--but the fact that Kira killed him is also a problem. Bites the Dust not only erases that person's death through time travel, but also seals them in a GroundhogDayLoop where anyone who interrogates him about Kira will explode, and then always explode in each successive loop. [[MakesJustAsMuchSenseInContext It's convoluted and confusing,]] but the end result is that, by the end of the day, all the people who are a threat to Kira are killed without Kira having to lift a finger.]] Part 6 had [[spoiler: the main villain of that getting the power to alter the universe's gravity, causing time to accelerate to the universe's end so that he could reset time to the way he wants it to be.]]
*** This is the whole schtick behind Koichi's Stand, Echoes. It starts out as an egg, which hatches when he needs it to, allowing him to [[spoiler: imprint sounds on a person, making it echo over and over in their heads.]] When that isn't enough, it evolves into a form that can [[spoiler: imprint words onto objects, granting the object the property of that word. For instance, making a solid, pointy rock become bouncy by imprinting "bounce" on it.]] And later on it evolves again to allow him to [[spoiler: increase gravity on a target to the point where it becomes helplessly pinned to the ground through some convoluted means of the words "three" and "freeze" (sort of) rhyming in English.]] Each new form has a smaller range, but Koichi can just choose to summon whichever version of the Stand he wants anyway. Koichi's pretty much a SwissArmySuperpower among Stand users.
** Part 5 protagonist Giorno eventually ends up with the mother of all new powers, [[spoiler:the power to basically be immune to everything, even attacks he's not aware of, and to subject anyone he kills to be stuck in an endless loop of deaths for all eternity.]] This was, of course, to combat a Stand power that was so convoluted that the English speaking fandom made a meme out of not being able to understand how it worked.
** Parts 1 and 2 only avoided this trope by making ripple powers a sort of SwissArmySuperpower.
* ''Franchise/PrettyCure'':
** ''Anime/YesPrettyCure5'''s Cure Aqua suddenly picked up the ability to turn her "Aqua Ribbon" baton into a sword. The reasoning behind this was that this allowed [[RuleOfCool an awesome swordfight]]. The sword returned during TheMovie for exactly the same reason.
** Cure Beauty of ''Anime/SmilePrettyCure'' is in the same boat, having being shown to create an ice sword once during her fight against Joker, then doesn't do it again until ''their'' movie. Although, Cure Beauty does later use her ice sword(s) again in the series.
** ''Anime/HeartcatchPrettyCure'' was incredibly bad with this, with the girls constantly coming up with more attacks than those before them ever had and rarely using them afterwards. Cure Blossom was the worse offender, creating a tornado attack, a spiral energy KamehameHadoken attack to counter a foe's similar attack, a ''Christmas-themed attack'' with Cure Marine and just randomly throwing out pink energy like ki blasts.
*** Hilariously, ''Anime/HappinessChargePrettyCure'' runs with it. Megumi, after transforming into Cure Lovely for the first time, is told that she doesn't have set attacks and just make stuff up. She runs with it.
* In ''Manga/MermaidMelodyPichiPichiPitch'', the characters are frequently granted new karaoke songs ([[MagicMusic the weapon of choice in the series]]) whenever the ones in the previous episode didn't work. This becomes somewhat ridiculous, considering these upgrades are manifested by the goddess the protagonists are attempting to summon, and [[spoiler:when they actually summon her, all she does is tell them to sing...]] Oh yeah, and that [[IntimateHealing amnesia kiss]]? Lucia gets that too. Randomly.
* In ''Anime/Persona4TheAnimation'', Yu tends to gain a new ability, such as Persona Change or Fusion, whenever a boss turns out to be too much to handle.
** Teddie conveniently recalling that his persona, Kintoki-Douji, can cast Energy Shower, which (just as conveniently) cures Enervation ("old" status). However, Kintoki-Douji ''can'' cast Energy Shower in the games, and is one of his default spells. It will still feel like this to people watching that aren't familiar with [[Videogame/Persona4 the source material]], however.
* ''Anime/{{Bakugan}}'' has the mechanical Bakugan (and to a lesser extent Helios) pull out new more powerful abilities towards the end of the season. Justified through off-screen upgrades.
* ''Manga/DragonBall''
** For most of the series whenever Akira Toriyama wanted to introduce a new technique, or to show off a better version of an established one, it would usually belong to Tien or Piccolo. Tien introduced Solar Flare, Aura Flare's, self replication, and flight while Piccolo introduced regeneration, size shifting, the Special Beam Cannon, and arm stretching.
** The innate ability to sense energy is meant to be quite rare in DBZ, hence why Frieza's entire army (and even Frieza himself) utilize scouter devices. Vegeta relied on a scouter when we first meet him - although he knew not to trust them entirely - yet by the Namek Saga he randomly gained the ability to sense energy all on his own. With the Ki sensing, however, it wasn't that Frieza and his minions couldn't do it, but they didn't know that it even could be done. Vegeta mentioned that after he found out it was possible, he easily taught himself the ability. However, he isn't as good at it compare to the Earthlings. In ''Super'', he learns Super Saiyan God Super Saiyan off-screen by training with Whis and, unlike Goku, he gained god energy without the ritual.
** [[TheHero Goku]] reads Krillin's mind when he arrives on Namek. This is given some LampshadeHanging, with Krillin asking "Where did you get such an ability from?!", and Goku replying he wasn't even sure that would work. The mind-reading does have some justification since Master Roshi and Korin can read minds better than him (Goku needs to physically touch someone for it to work), and Roshi claimed that any high-level martial artists can do it. In ''Super'', he learns to combine [[spoiler: Super Saiyan God Super Saiyan and the Kaio-Ken]] off-screen and no one knew about it, not even Vegeta who trained with Goku for three years in the Hyperbolic Time Chamber. The reason why he never [[spoiler: combined the Kaio-Ken with any of his other Super Saiyan forms was because it was physically impossible since Super Saiyan alone is a stressful power-up and combining the Kaio-Ken with it is suicide. Super Saiyan God Super Saiyan only works because it's a calm transformation with great energy control]].
* ''Franchise/SailorMoon''
** Happens about once per story arc when it isn't leaning on the EleventhHourSuperpower instead. Also combines with SoLastSeason in that suddenly gaining new abilities usually means the characters cease using their old ones.
** The rest of the cast just tend to get powerups because the plot usually needs them to get boosts around the same time Usagi does. Most egregious in the Makaiju arc in the ''Anime/SailorMoon'' R anime, in which the four Guardian Senshi each get a CharacterFocus episode that concludes with them using a new ability to highlight their emotional connection to the episode's storyline. For the most part, they also never use these powers again outside their CharacterFocus episode.
* ''Manga/{{Bleach}}'':
** The Hougyoku's original power was to dissolve the barrier between Hollow and Shinigami, known as hollowfication. This is the explanation for the creation of the modern Arrancar and also the Vizards. Later on, Aizen claims it actually alters reality based on the wishes of the user, but only if it's possible to achieve those wishes without the Hougyoku. However, it was hinted all along that the original explanation of its power was wrong. If it was supposed to cause hollowfication, why was its original use to try and '''reverse''' hollowfication instead? Also, Aizen's own knowledge has turned out to be inaccurate as well, so the second explanation may be as inaccurate as the first explanation.
** In the [[{{Filler}} Invasion]] [[{{Anime}} Arc]]. the villain's zanpakutou is this. [[FillerVillain Kageroza's]] zanpakutou has the power to manipulate space/time. Then it's revealed to have the power to teleport and duplicate. Then it has the power to resurrect "dead" reigai. Then, when Ichigo is about to defeat the villain, his zanpakutou is revealed to have a cloning ability. The apparent damsel of the arc, [[CreatorsPet Nozomi]]'s zanpakutou has the power to drain reiatsu. Then it's revealed to be able absorb the attacks of anything thrown at it, combine it with her own power and throw it back as a more powerful attack. Then it's revealed that Kageroza's and Nozomi's power are two halves of the same original zanpakutou and, when recombined, the zanpakutou gains all the powers in combination which suddenly results in the power to destroy the entirety of Soul Society with a single activation command. And, somehow, the original zanpakutou never had any of these abilities at all until the owner, fed up with being treated as weak, turned evil and decided to obtain more power by splitting himself in two and recombining himself (how this makes him more powerful and gives him powers he never previously possessed is never explained).
** While being attacked by Yhwach, Ichigo spontaneously uses a new power to prevent himself from being ImpaledWithExtremePrejudice. However, this is immediately explained in-story in a manner that ties in to both his spontaneous healing in his first fight with Kenpachi and with the power restoration technique that was used on Uryuu.
** Each of Yhwach's elite guard shows off a new ability when they're about to be defeated, even if they should already be dead. And when that ability doesn't prevent them from being defeated, they pull out ''another'' new power. Lille Barro perhaps being the worse given that his first [[OneWingedAngel unexplained power-up]] comes ''after'' his head has been cut off, and the next after his own power has been turned against him.
* ''Manga/SoulEater'' has quite a few of these, both in manga and the anime -- most blatantly [[spoiler:in the last four episodes of the anime, where Black Star, Kid and Maka suddenly acquired DeusExMachina-like superpowers in that order after being beat to the floor by the villains.]]
* Quite common in ''Anime/{{Pokemon}}'', although mildly justified based on the source material. However, an unusual variant of this trope also appears, in that Pokemon which Ash has ''never used before'' often turn out to be inordinately strong. One of the best examples of this is the Indigo League arc of the original Johto season; Ash's never-used-before Muk basically helps Ash sweep his way all the way up to the final match, whilst his likewise previously unused [[GiantEnemyCrab Krabby]] not only won its very first battle on the field, but promptly turned into the even more powerful Kingler.
** Even earlier than that, [[ManiacMonkeys Primeape]] went from a just-caught, untamed raging monster into Ash's loyal and highly effective bruiser who singlehandedly wins a Fighting type tournament. And is then promptly given away to a Fighting type specialist trainer.
* In ''Manga/TsubasaReservoirChronicle'', this is effectively the main purpose of Mokona's 108 Secret Abilities power.
* ''Manga/MajinTanteiNougamiNeuro'': Neuro's 666 tools of the Demon World and 7 Tools of the Demon Emperor. That's 673 different powers he can pull out of thin air whenever he needs to.
* Kogarashi from ''Manga/KamenNoMaidGuy'' has a ''large'' [[ComboPlatterPowers platter of various powers]], many of whom only show up once to advance the plot ([[HeroicComedicSociopath and cause massive amounts of comedic havoc for everyone else in the vicinity]]) and are never touched on again. The sheer bizarreness of most of these powers -- like knowledge of every gourmet recipe in the universe and the ability to [[BrownNote paralyze people with his voice]] -- makes most of them fall squarely under the RuleOfFunny.
* Ryoko of ''Manga/TenchiMuyo!'' certainly falls into this category when she gets immobilized from the neck down and shoots a bunch of lasers from her ''hair''. But as cool as this looked the attack did her no good whatsoever.
* In ''Anime/CodeGeass'', Suzaku's "live" command, which initially took over his body and forced him to survive by any means against his will, is significantly repurposed in Turn 22. Now Suzaku can consciously activate its effects in order to become a better fighter. The only way this makes sense if Suzaku can [[FromACertainPointofView re-interpert what "live" is supposed to mean]].
** Part of it might be that it forces Suzaku to act in whatever way is most likely to ''not'' get him killed. For example, fighting both Kallen at her best [[spoiler: and with a really powerful new machine]] and [[spoiler: Bismarck Waldstein, the world's strongest Knight,]] cause his Geass to activate and take some other action, rather than running away, because they outclass him so much that exposing his back to them will give them the opportunity to kill him. In both cases, this results in him exposing himself to a seemingly greater danger - a very large explosion, and a rock slide, respectively - because he has a better chance of surviving those, and he does. During his [[spoiler: second fight with Bismarck Waldstein]], Suzaku makes his command kick in late enough to force him to win, which presumably works because he knows the Lancelot Albion has a better machine and the "live" effect allows him to not hold back, which cancels out any intimidation factor caused by Bismark's ability.
** The sudden ability to remember what happened under the command's effects, however, is completely unexplained, and has no other examples during the original TV series.
*** The possible implied explanation is that all the times the command activated before Turn 22, he was trying to either kill himself or let himself be killed. Now that he's not trying to die, the Geass doesn't react as strongly. We've seen that long term Geass effects be bent or broken completely.
* In ''Anime/TransformersVictory'', Deathsaurus uses Transformer-eating insects to try and kill Star Saber. They turn out to be vulnerable to cold, and then Victory Leo decides to reveal he has a freeze power.
* In ''Anime/YuGiOh'', the Millennium Items seem to have their standard powers, plus random other powers used in one or two situations, then forgotten for the rest of the show, even in situations where they would have been useful. For instance, in the manga Yugi holds his puzzle asking it to show him where Jounouchi is, and it does it.
** There's also the Millennium Ring, which near the end of the Pegasus arc showed the power to manifest the effect of Duel Monsters cards as real, allowing Bakura to use Chain Energy to bind Pegasus' goons and summon the Man-Eater Bug to attack him. This power is never brought up again.
** Being MerchandiseDriven, this often happens with brand new cards just revealed, and often these cards are A) highly situational to the point in any real deck they'd be dead weight, and B) never seen again after their one usage. On occasion the new card that is used is a real life card that they just didn't use in the show before (such as Skilled Dark Magician), other times the card is completely made up with powers verging on GameBreaker levels (such as ''the entire Orichalcos archetype'').
** The Winged Dragon of Ra is clearly this, revealing a new secret ability ''every single time'' it gets played. A full list of its abilities: its ATK and DEF are equal to the ATK and DEF of the monsters tributed to summon it, you can pay all but 1 Life Point to increase its attack by the same amount, you can pay 1000 Life Points to destroy a monster on the opponent's field, and you can tribute other monsters to add their ATK to Ra's ATK. And that doesn't count the requirement one needs to have Ancient Egyptian heritage and has to recite an ancient chant in order to summon it, and the immunity to card effects it shares with the other god cards. And the aforementioned effect to pay life points and increase Ra's attack? It can be reversed, allowing the user to to take back all of those attack points as life points by using ''De-Fusion''.
** Spoofed mercilessly ([[AffectionateParody along with everything else]]) in ''WebVideo/YuGiOhTheAbridgedSeries''.
--->"Conveniently, my Millennium Puzzle allows me to put souls back into their original bodies!"\\
"I activate a spell that allows our monsters to trade places! Which would be completely useless in any other situation."\\
"I have placed a part of my soul inside the Millennium Puzzle, because apparently I can do that."\\
"Now I shall use Mega-Ultra Chicken's secret ability that I just this second made up to convert my Life Points into Attack Points, merging me with the beast itself!"
** ''Anime/YuGiOhGX'' season 4 has Trueman, who exhibits a new power in nearly every appearance, ranging from teleportation to cloning to possession to shapeshifting to ripping through the dimensional fabric to thought manipulation.
** In ''Anime/YuGiOh5Ds'' [[AWizardDidIt the Crimson Dragon did it]]. The Crimson Dragon's abilities are never really explained at any point, so the Signers can showcase new ones at their leisure. Most notably the [=Savior/Majestic=] Dragon, which Yusei and Jack get during their duels against Dark Signers. It doesn't actually exist in their deck, it just appears on top whenever they need it.
** ''Anime/YuGiOhZexal'' has the [[TheMagicPokerEquation Shining Draw]], which literally creates a card that will have the exact effects needed to beat the opponent, no matter how convoluted, up to a monster that lets him attack outside of his battle phase, an ability seen on no other card in the game.
** Deconstructed in the second episode of ''Anime/YuGiOhArcV''. Here, the new monsters in the series, Pendulum Monsters, are capable of being created by the main protagonist's pendant. However, he doesn't fully understand how they work right off the bat, and even believes that they only come out when he's in a pinch, and when he reveals how he got them to a crowd of people, he's accused by them of cheating in his duels.
* Parodied in ''Manga/FullmetalAlchemist'' where Ed, separated from Al and feeling rather desperate, tries to "CONVENIENTLY AWAKEN TELEPATHIC POWERS!" to contact him. It doesn't work.
** Though later revealed in the manga omake, it ''did'' work. He just didn't reach Al. [[spoiler: He reached ''Pinako''.]]
** Scar displays a rather odd power during an episode of [[Anime/FullmetalAlchemist the 2003 anime version]]. Trying to find out where the Elric brothers are, he places his arm on a stack of their research papers, and gathers all the words into, what can only be called, a knowledge ball. [[BigLippedAlligatorMoment This ability is never mentioned beforehand, and never spoken of after the scene]].
* ''Manga/DetectiveConan'': Conan can do anything. ANYTHING. He can drive a car, scuba dive, shoot a gun, drive a boat, drive a Jetski, fly a small plane, and FLY A HELICOPTER (which is completely different from flying a plane). Why can he do these things? Because he "learned in Hawaii!"
** The knowledge of flying a helicopter is handwaved as him using a simulator at a local science center "when he was a kid" (which is still probably ''very'' different than flying an actual helicopter), which gets the rather amusing response from Kogoro of "You still are a kid!"
* Haru, the lead in ''Manga/RaveMaster'', actually has the power to acquire new powers when he's in a sticky situation thanks to the Rave of Wisdom. The technical explanation is that he has a sword with ten (preset) forms, and he learns a new one whenever he happens to need it most. This manages to avoid being an AssPull at several points because he either obtained some powerful artifact to grant him another sword, he had to get some reforging done before he could access one form, and another form was used by a villain before he figured out how it worked.
* ''Manga/OnePiece'': Always present to some extent[[note]]Plot Plot No Mi, as the fandom calls it[[/note]], though normally the powers are natural outgrowths of previously existing abilities or brand new items with some degree of HowDoIShotWeb. However, in the Enies Lobby Arc, it's practically endemic, with every single character pulling bizarre new abilities and weapons out of nowhere. Oda has said he doesn't like to do training arcs like in other Shonen series. Instead, he'll have a character pull out a new ability and then go into a flashback about how they trained for that ability off-screen.
** Luffy learned how to use Gear Two and Gear Three. He supposedly perfected both techniques in the roughly week and a half after being beaten to near-death in the previous encounter. Luffy also learned how to flash-step via mimicry mid-battle.
** As Sogeking, Usopp unveiled a brand new super-slingshot with tech-boosted firepower, range, and accuracy. It's not clear when exactly this weapon was built, as Usopp had been holding the DistressBall for at least a day and a half before arriving at Enies Lobby, and the weapon definitely would've prevented much of that distress.
** Nami showed off the upgraded Clima Tact, which Usopp also put together at a vague point in the timeline.
** Sanji's Diable Jambe technique. He had more time than the others to figure this out, to some extent, as he hadn't been in the same dire battle as the other Strawhats from several hours prior. This ability in particular seemed almost tailor-made for the situation, as he was fighting an enemy that was [[{{MadeOfIron}} especially resistant to normal blows]], but not fire.
** Zoro activated a brand-new nine-sword-style goddess form. Unlike the above, there was basically no attempt to explain this, and the form's properties are still very unclear. Earlier, Zoro had outright banked on this trope while fighting the literally MadeOfIron Mr. 1. Zoro doesn't know how to cut steel yet, but is sure he'll figure it out with his life on the line. He does.
** It works more logically after the TimeSkip, as all the characters had two years to train, but aren't going to exhibit all of their powers at once. Across Fishman Island and later arcs, the Straw Hats seem to bust out very new powers according to plot demands. The most off-the-wall being that Brook discovered the true basis of his devil fruit, which isn't about bringing him back to life so much as it is about giving him super-soul-powers that not only include the ability to come back from the dead once, but also allow him to astral-project himself, and use ice attacks. He also developed a degree of limited MindControl through his music.
** The villains aren't immune to it either, as Blackbeard shows up at the end of Whitebeard's attack on Marine HQ and suddenly displays the ability to [[spoiler: steal devil fruit powers and use two of them at once]]. No attempt is made to explain the exact mechanics of these abilities, except that the latter of which is explicitly attributed to Blackbeard himself, not his own Devil Fruit powers.
* Kenshiro's fighting style of Hokuto Shinken in ''Manga/FistOfTheNorthStar'' is made of this trope, doing whatever Kenshiro happens to need at the time, including making mohawks' heads explode, giving Lin the ability to talk, making a thug's mouth move by itself to tell truthful answers to Kenshiro's questions, and even [[CrowningMomentOfFunny making a thug think he knows Hokuto Shinken, try to use it on Kenshiro, and utterly fail]].
* In the final Season 1 episode of ''Anime/UchuuSenkanYamato'', Dessler appears out of nowhere in a ship and fires a [[WaveMotionGun giant energy blast]] at the Yamato. Sanada activates a device with reflects the beam back onto this source. This device was never seen used by the humans before (only Sanada seemed to know its existence), and despite its seeming usefulness, is never used or mentioned again.
* ''Anime/StarDriver'' is particularly bad about this. Practically every other episode in the series ends with [[TheHero Takuto]] suddenly revealing that he has some hidden power that just happens to work perfectly against whatever enemy he's fighting, and using said power to OneHitKO his enemy. The show justifies it by saying that Takuto is ''far'' more experienced than most of his enemies, and he's deliberately holding back most of the time so they don't know how good he really is.
* Spoofed in the fifth episode of ''Anime/TigerAndBunny''. When Wild Tiger and Barnaby are in a pinch and [[HourOfPower almost out of time]], their PoweredArmor automatically switches to the the brand new Good Luck mode Saito installed and they manage to incapacitate their opponent just before the clock runs out. So what does Good Luck Mode actually do?
-->'''Barnaby:''' So this new mode increases our power?
-->'''Saito:''' [[spoiler:Not one bit! It makes you look cool, though.]]
** Also spoofed in the eighth audio drama (a comedic AlternateUniverse where Kotetsu and Barnaby are actual [[BuddyCopShow Buddy Cops]]), where the following exchange takes place as they confront the villain.
--->'''Barnaby:''' No good! I'm out of ammunition!
--->'''Kotetsu:''' Me too, Riders!
--->'''Barnaby:''' But you know, I actually have pretty amazing powers! I just normally keep them secret!
--->'''Kotetsu:''' Whaaat!? ... Actually, I got the exact same powers just yesterday!
* ''Anime/SuperAtragon'' gives us a battleship that does this: The ''Ra'' gains several the following new abilities with no explanation; most are shown exactly once:
** A self-leveling bridge.
** A ''Franchise/StarTrek''-like bubble-shield.
** [[IfItSwimsItFlies The (completely gratuitous) ability to fly]].
** Weaponized, rocket-propelled anchors.
* For nearly a hundred episodes in ''Manga/YuYuHakusho'' the audience has know Kurama to be a [[GreenThumb plant user]]. But in the fight against [[spoiler: The Elder Toguro]], he used a smoke screen? Where'd that come from?
** The biggest offender was Yusuke being resurrected as a powerful half demon and then having a demon god take over his body conveniently to win.
* ''Manga/InazumaEleven'' anime develops itself into this. At first, many skills the team learn come from books and manuals, but by the third season, characters repeatly pull out new things whenever the plot demands them. In the movie, the protagonists learn to use super power abilities without any explaination just so they can beat the Ogre, who's argubly stronger than the series' world cup teams.
* ''LightNovel/HaruhiSuzumiya'': In the movie that Haruhi filmed for the arts festival, Mikuru's character had the ability to fire a [[EyeBeams "Mikuru Beam"]] from her left eye. At the end of the movie, Itsuki's character randomly and conveniently awakens his esper powers just in time to defeat the evil alien. [[spoiler: Thanks to Haruhi's subconscious RealityWarper abilities, Mikuru actually did get a "Mikuru Beam" that continuously endangered the lives of the film crew, especially Kyon. Yuki, thankfully, was able to suppress these abilities...at which point Haruhi would give Mikuru a new type of beam that Yuki had to deal with]].
* ''Anime/MazingerZ'' had a number of powerful attacks that were only used once or twice and never seen again. Among them were a "Refined Rocket Punch" which was a tougher arm for Mazinger-Z that fired a much stronger RocketPunch and the ability to ''magnetize its fingers''.
* Franchise/{{Gundam}}:
** ''Anime/MobileSuitGundam'' had the "Super Napalm", an odd weapon that was used to destroy the remains of Side 7's Operation V project.
** ''Anime/MobileSuitZetaGundam'' had Kamille pull out a lot of attacks out of his ass during the final two episodes, essentially doing Super Robot things in a Real Robot setting. It was later explained that the Zeta had a psycommu-based device called the Bio-Sensor, which amplified Kamille's power to do crazy stuff.
** ''Anime/MobileFighterGGundam'' had Domon Kasshu take a page out of the above Kamille's book, except instead of limiting himself to the final episodes he indulged in the entire second half of the series, pulling out attacks like the "Burning Shadow" and "Burning Dash" that he would use in one match to counter one very specific opponent and then promptly never use again.
** In ''[[Anime/MobileSuitGundamAGE Gundam AGE Cosmic Drive]]'', the mobile suit gets upgrades increasingly frequently. Even after the most tear-jerkin scene, [[spoiler: where Desil kills Yurin]], Vargas stills pop up in the middle of the fight, proudly and happily presenting [[MechaExpansionPack a new armor pack.]]
* ''Anime/TengenToppaGurrenLagann'', full stop. To the point where Simon develops ''teleportation'' just to punch someone!
* ''Franchise/{{Digimon}}''
** The entire franchise is in LOVE with this trope. Granted, that is how it works. A favorite example of fans is in the Myotismon Saga/Arc where Gabumon and Agumon are magically able to unlock their Mega forms.
** ''Anime/DigimonFrontier'' ESPECIALLY loved this trope. The whole point of the first sixteen or seventeen episodes was to literally get the spirits and evolve to higher levels. Especially displayed when Kouji Minamoto and Takuya Kanbara gain Double Spirit/ Fusion Evolution. With the power coming from an egg. No joke. Watch Episode 26.
* ''Manga/AttackOnTitan'' Eren's [[spoiler:Titan Shifter abilities (all of them)]] progressively manifest when he desperately needs them. Of course he is [[{{Handwave}} set up]] as suffering memory loss and nobody is telling him [[HowDoIShotWeb how any of this works]]. Uncertainty and not knowing just about anything is a common recurring element in the story.
* ''Manga/MagiLabyrinthOfMagic'' has an attempted invocation by Alibaba, who can't figure out how to master Djinn Equip yet. He then throws himself into a battle, hoping that when the chips are down he'll be able to do it. [[WrongGenreSavvy He's (almost) wrong]] and would have died were it not for a BigDamnHeroes moment by a friend of his.
* ''Manga/FairyTail'':
** While fighting Erigor, Natsu is knocked off a bridge without Happy to save him, but manages to change the make-up of his fire to use it to as a sort of rope. He never uses or even mentions it again. In the anime, this is explained as him emulating a trick Macao showed him when he was a kid. Macao's [[AllThereInTheManual bio]] states that he uses the same fire magic as Bora, the first villain, and the anime shows this, so it's not like there's no [[ChekhovsGun precedent]] for it.
** Also, Lucy's forced dismissal of Celestial Spirits, "learned" when fighting Sherry. It's not completely forgotten later on and is used a few more times (mostly as a joke, but to good effect when fighting Angel), but it comes completely out of nowhere. At least that power is a logical step up from her previous powers.
** In order to defeat Zancrow, the Fire God Slayer, Natsu empties himself of magic so he can eat the previously inedible god flames, then somehow combines them with his own flames that were supposed to have run out. Later on against Master Hades, Natsu eats [[spoiler:Laxus's lightning]] when it's stated that the last time he tried it made him sick. This time, it works, and the combination of powers gives Natsu a new SuperMode that he can use from then on.
** Natsu tends to serve as a guinea pig for this sort of thing when it comes to introducing unique abilities for Dragon Slayers, with other Slayers stuck in a similar situation intentionally emulating him because, hey, if he could do it, why can't they? Devouring large amounts of magical energy to obtain [[SuperMode Dragon Force]]? The guy he first used it against (Jellal) intentionally replicates the phenomena again to help him defeat [[ArcVillain Zero]] and [[BlowYouAway Wendy]] does it herself with Magic-saturated air to defeat [[OurDemonsAreDifferent Ezel]]. [[spoiler:Eating Laxus's lightning]] to gain a new SuperMode? Gajeel, [[spoiler:Rogue in the BadFuture, and Sting]] all do the same thing with various elements to gain their own {{Super Mode}}s.
* ''Manga/DailyLifeWithMonsterGirl'':
** [[SlimeGirl Suu]], being one of the few cast members based on a modern monster rather than a mythological one, tends to manifest new abilities whenever the plot requires it, with it being {{lampshaded}} that there's really not a lot of info on how slimes work. Most egregiously, at one point it's revealed that she's capable of reading minds.
** [[SpiderPeople Rachnera]] is a close second: her silk is used for a number of purposes, including the ability to make clothes on the fly, eavesdrop on others and make a [[NinjaLog decoy puppet]] that looked exactly like Kimihito.
* PlayedForLaughs in ''Manga/TheDisastrousLifeOfSaikiK''. Saiki has a seemingly-endless list of psychic powers, but [[PowerIncontinence he has trouble controlling them]] and [[BlessedWithSuck they seem to cause him all kinds of trouble]].

[[folder:Card Games]]
* [[MagicTheGathering Planeswalkers]]: Old walkers are able to do virtually anything according to the comics and novels, and Post-Mending walkers are capable of quite a bit (shown by them getting printed with new abilities). The players themselves are old walkers: literally capable of casting anything they have in their decks (provided certain limitations). But this is kinda the point of playing.

[[folder:Comic Books]]
* Franchise/{{Superman}}:
** Superman started out faster than a speeding bullet, more powerful than a locomotive, able to leap tall buildings in a single bound and invulnerable to anything less than a bomb. Since then he's learned to fly, to blow like a hurricane, to survive nuclear explosions (though just barely), chill things with a [[SuperBreath puff of breath]], shoot [[EyeBeams lasers from his eyes]], and use XRayVision. And that's just the powers that have lasted.
** Interestingly, a lot of this stems from various media adaptations, particularly the WesternAnimation/{{Superman Theatrical Cartoon|s}} shorts; originally the brothers Fleischer ''wanted'' to stick close to a relatively limited powerset, but animating him just "leaping" everywhere was time-consuming and expensive (even with their extravagant-for-the-time budget), so they asked DC "can we just make him fly?" DC said "Sure", he flew in the cartoons which introduced a ton of people to the character who then bought the comic and complained to DC, asking why Superman didn't fly like he did in the cartoon... and, well, we were off to the Super-races.
** Superman's MirrorUniverse counterpart Ultraman actually has this as his superpower: exposure to Kryptonite, rather than harming him, causes him to develop new abilities (at least in his first appearance. Later on this was changed to Kryptonite being necessary to sustain his full levels of power).
** And Red Kryptonite (occasionally, in some continuities) lets the "regular" Superman develop new abilities, albeit temporary ones.
** Van-Zee, Superman's lookalike from Kandor, demonstrates [[http://www.superdickery.com/super-weaving/ Super Weaving]]. He's just using super speed to, er, weave really really fast.
** In one strip, Comicbook/LoisLane is going blind and she wants to see a play based on herself before this happens. But the play is only a script, so Superman uses super-puppetry to make it appear that actors are performing on stage (Lois' vision is blurred so she doesn't notice). He also uses "super-memory" to learn the script, even though he could just ''read'' it given that he's offstage.
** Other silver age classic powers: super-hypnotism, super-kissing (don't ask, really), and super-mimicry.
** "Super-hypnotism" -- though not called that at the time -- was actually acquired at a very early point, certainly by 1940 at the latest (he hypnotizes Lois in at least two different stories that year alone.)
** The original TV show mostly restrained itself from this, but huffed this trope twice, once to give Superman the ability to phase through walls, and once to let him split himself into [[strike:multiple]] two Supermen. Both of these powers vanished after the episode. The splitting ability came from his dense molecular structure (at the time, the explanation for his invulnerability) meaning he had enough mass to make up two normal people. The two were significantly weaker than when they were together creating dramatic tension when they couldn't merge.
** In one episode of the Franchise/{{DCAU}}, Superman teams up with Robin to search for Batman, and displays his super-mimicry, explained as him having extraordinary control of his vocal muscles, to first mimic Batman, then Robin himself. This completely freaks Robin out, and he demands that Supes [[NeverSayThatAgain "Never. Do that. Again."]] Superman never uses this power again.
** [[http://comiccoverage.typepad.com/comic_coverage/superpowers-that-time-forgot/ There's plenty more examples from the comics.]]
** The basic assumption was that, for any ability a normal man might have, Superman could do it or learn to do it much better. If a man can blow out a candle, then Superman can blow out a forest fire. The problem lay in that the writers didn't consider how ventriloquism or hypnotism really work, so Superman was shown ''literally'' throwing his voice, or hypnotizing people almost effortlessly.
** The time travel ability is a logical extension of the fact that they'd already established he could fly faster than light; the real question is how he ever broke the light barrier ''without'' time traveling.
** This didn't end with the Silver Age by the way. The modern Superman has been shown to use the psychic martial art of Torquasm-Vo which in one instance allowed him to ''alter reality''.
** Superman's set of powers, while extensive in number, were actually fairly set in stone by the early 1960s, when heat vision (the last major power addition) became a stand-alone power from his x-ray vision, and the yellow sun explanation for his powers came into use. (He'd use "the heat of his x-ray vision" to melt things in 50s stories.) The above mentions of "super-weaving"/"super-puppetry"/etc. are just using his usual powers (super-speed, etc.) to do some task in a creative manner, and not actual "powers." The ''extent'' of his powers, especially invulnerability and strength, were reduced post-1960s (and especially in the Byrne revamp), with a few powers outright tossed out by Byrne (in particular, time-travel and interstellar travel using his super-speed, super-hypnosis, and super-ventriloquism). The ability to use his super-breath to create freeze breath apparently fell prey to this for awhile, until it was brought back in 2000s stories.
** Not that there weren't outright inexplicable new powers sometimes. In one issue, he managed to ''rewire complex circuitry'' with his vision to stop some evil machinery of ComicBook/{{Brainiac}}'s, and another time he somehow used his vision to attempt a ''phone trace.'' It's especially {{Egregious}} with Silver Age Superman ''because'' of the number and extent of his established powers.
** This applies to some of his supporting cast as well. In an old issue of ''Superman Family'', Comicbook/LoisLane assumes the identity of a Russian ballerina after [[MuggedForDisguise knocking her out and leaving her bound and gagged in a closet]]. She's suddenly able to dance well enough to fool the audience ''and'' the other Russians, which she attributes to years of ballet lessons she supposedly had as a child.
** Although Comicbook/{{Supergirl}} was created in the late Silver Age and she was so overpowered like her cousin, she was not liable to come up with new powers every issue. Still she had super-intuition -a power unique to her-, used super-ventiloquism, in ''Comicbook/ActionComics #258'' she used super-aiming and in ''[[ComicBook/Supergirl1972 Supergirl Vol 1]]'' issue #1 she uses [[VacuumMouth Super-Suction Breath]] to capture a serial killer (she draws out the air out of a cab so the man in there faints).
** Parodied in ''ComicBook/Supergirl2005'' storyline "Way of the World". Supergirl fights a villain that at one point brags about his new powers:
--->'''Luzano:''' Hyper-Strength! Hyper-Speed! Plasmagenesis! Yes, that's a word! Hyper-sensual perception!\\
'''Supergirl:''' (incredulous) "Hyper-sensual"?
** Parodied in the third issue of ''ComicBook/SupergirlCosmicAdventuresInThe8thGrade'' when Linda tries to gain new powers combining different types of Kryptonite. She gains a bunch of useless powers until she gets something useful after several attempts:
--->'''Supergirl:''' You gotta... be kidding. The power to overcook waffles...? How is that even a power?
* Franchise/SpiderMan:
** Antagonist ComicBook/NormanOsborn is able to come BackFromTheDead (via WakingUpAtTheMorgue) thanks to a healing factor he wasn't even aware he retained. Then again, it's not surprising that he'd be unaware of a power he had to ''[[DieOrFly die]]'' to use.
** Spider-Man also has in his rogue's gallery a villain called "The Answer", whose powers are ''defined'' as "whatever is necessary in the current situation".
** In ''Comicbook/UltimateSpiderMan'' [[spoiler: Peter Parker later comes back from the dead after it turns out that the serum that empowered him (as well as Miles Morales and Norman Osborn) makes them functionally immortal. Thereby explaining Osborn's JokerImmunity.]].
* ''Comicbook/XMen''
** Darwin, whose body will [[AdaptiveAbility evolve on the fly to meet the problems in the situation]], even though Darwin has no control over what evolves or how it works. Lampshaded during ''World War Hulk'' when his power decided the best defense against a rampaging Hulk was...to not be there, as illustrated by his teleporting away. Which was pretty brilliant, although the power originally created a Gamma Energy Draining power to drain power from the Hulk to weaken him, but the Hulk is one of those sorts who fit the 'generates more energy than the enemy can hope to drain' trope so Darwin was getting nowhere and after being knocked unconscious by the Hulk his power reasoned it had no hope of defending against the Hulk directly and got Darwin several states away where it was relatively safe.
** Similarly, the mutant Lifeguard will develop whatever power ''will be'' necessary next to save lives. So, unconscious precognitive adaptation. Like Darwin, it sometimes turns out that gaining the power necessary to save lives ''doesn't'' mean gaining the power necessary to ''defeat the enemy.'' On top of that, apparently, it only helps her save ''other'' people's lives. As often as Darwin she is more inconvenienced by a power she gains, or must [[WhenAllYouHaveIsAHammer make creative use of something]] that isn't the SuperStrength or EyeBeams she'd rather have had.
* Comicbook/TheAvengers have ComicBook/ScarletWitch, who has possibly the most ill-defined set of powers in all of Marvel Comics. DependingOnTheWriter she can be a mutant RealityWarper, a mystical sorceress, both, or something else altogether.
* ''ComicBook/MartianManhunter'' was prone to this, at times having the power to control magnetism, strain gold from water, and ''[[ArsonMurderAndJaywalking create ice cream with his mind]]''.
* Happens to ComicBook/{{Aquaman}} every so often. In that case, it's just as much New Powers as [[NeverLiveItDown Lack o]][[AtlantisIsBoring f Respect]] Demands.
* ''Franchise/XMen'':
** Marrow had her heart torn off her body by Storm, but later was revealed to be alive. How? Spare heart.
** ComicBook/{{Storm}} can slip into this herself (her use of [[LightningCanDoAnything lightning in increasingly improbable ways]] qualifies), it even bleeds into other adaptations. For instance, did you know that she can apparently use Cerebro in the Black Panther animated series?
** ComicBook/{{Magneto}} started off with the ability to control metal magnetically, then developed the ability to fly with a reasonable enough explanation. Then, as stories became more ambitious, he was suddenly able to control the entire electromagnetic spectrum, which effectively made him invincible, so long as no one managed to get in a cheap shot. He could even go toe to toe with the freaking Phoenix (admittedly, this was before the retcon of the Phoenix being a vastly powerful cosmic entity, but even so, it's no mean feat)! Of course, then there's the ''Planet X'' story by Creator/GrantMorrison, in which he's powerful enough to (somehow) control gravity and ''time.'' (Grand Unified Theory?) Of course, in that case, he was retconned into being Xorn posing as Magneto, while the real Magneto was living in the ruins of Genosha. However, stories like ''ComicBook/AvengersDisassembled'' when he demonstrated the ability to basically stargate across continents to get his daughter, which are canonically him, don't under-sell his ludicrously vast pwers. And ComicBook/{{Ultimatum}}, in which ComicBook/UltimateMarvel Magneto is able to use his powers to [[spoiler: shift the magnetic poles of the Earth, [[ArtisticLicensePhysics which causes massive weather shifts, which causes massive tidal waves to destroy almost all of the East Coast]].]] Admittedly, he needed Mjolnir to do it.
** Creator/GrantMorrison used this trope by [[strike:an AssPull]] a CerebusRetcon in his run on ''X-Men'' by introducing "secondary mutations", which would grant entirely new sets of powers to mutants, even years after they first gained their powers. This was his excuse for letting Emma Frost turn into living diamond for no obvious reason besides RuleOfCool. [[spoiler: It turns out later that Emma was given that ability by Cassandra Nova so she could survive the Mega Sentinel attack as part of her plan to return if defeated. However, ''other'' characters get interesting (or terrifying) secondary mutations too.]]
** One Creator/ChrisClaremont story suddenly gave Storm SuperSenses, because she could feel the effect everyone around her had on the local air pressure or something.
** Dave Cockrum used to drive Claremont nuts by constantly giving Nightcrawler new powers almost every issue back in the earlier X-Men days. Such as invisibility in shadows, or wallcrawling (the first of which got [[OrwellianRetcon Orwellian-retconned]] in reprints, with the latter just being quietly dropped)
** Professor Xavier's less-seen powers include telekinesis and the ability to give other people telepathy.
** As originally written pre-{{Retcon}}, [[ThePhoenix Phoenix]] was merely ComicBook/JeanGrey's "ultimate potential as a psi." She'd never shown that she was capable of that level of power before, and later stories brought in outside influences, but originally Jean spontaneously unlocked awesome powers when faced with death.
* ''ComicBook/{{Legion of Super-Heroes}}'':
** Ra's Al Ghul set the Moon on a collision course with the Earth. This gave off "hypertaxis energy", which caused humans to evolve to survive a threat before it happened.
** Tyroc had the power to warp reality with his [[MakeMeWannaShout screams]]. (Of course, this made the "screaming" part just color... no pun intended.) He could do nearly anything, from teleportation to pyrokinesis to... making it rain glue. The character was soon written out; common wisdom is that the writers had no idea what to do with him. In his recent reintroduction he seems to have been {{Retcon}}ned into having more conventional Banshee/Black Canary [[MakeMeWannaShout scream powers]].
** Duplicate Boy had the ability to copy ''any power he wanted'', including those he made up. Of course, his abilities were rarely used properly by the writers. He could copy the powers of anyone he's ever met including multiple powers at the same time much like the Super-Adaptoid. So he was effectively the most powerful being in the 31st Century, which is why they had a 'the rulers of your homeworld deem you must remain here to protect it' restriction on him along with the rest of his team for why he in particular never had an impact against the villains that showed up after his introduction.
** The villain Nemesis Kid had the ability to temporarily gain whatever power he needed to fight any single opponent. This one was used just as badly; he was killed in hand-to-hand combat by Queen Projectra -- without her using her illusion powers -- the only given reason why his ability didn't provide him with invulnerability as well as immunity to illusions was being too ''intimidated'' to concentrate on activating his power. One would suppose he would gain invulnerability against physical attacks against any foe capable of throwing a punch... Nemesis Kid's powers explicitly only worked on one power at a time. That's why Princess Projectra was able to simply beat him to death: His power was occupied nullifying her illusions.
* ComicBook/TheSentry is one of the more blatant examples of this; at first, he was a standard FlyingBrick with additional LightEmUp powers and PsychicPowers (sufficient to wipe everyone's memory of him), albeit strong enough to - with effort - contain a Cosmic Cube. Then his dark side, the Void, demonstrated all sorts of abilities like WeatherManipulation and combat tentacles strong enough to break every bone in the Hulk's body. After that, it steadily progressed up to grand scale Molecular Manipulation and being a flat out RealityWarper (which goes some way to explaining his constantly changing origin) - there's a reason that one theory about him holds that he's actually a sentient Cosmic Cube, like Kobik. Either way, he can't die unless he wants to, and is only generally restricted by his rampant neuroses. Then he came back from the dead as one of the Apocalypse Twins' Horsemen of Death, totally without the Void (apparently it got bored and left for the White Hot Room) and even crazier and more powerful than ever.
* The ''Comicbook/DoomPatrol'' villain "The Quiz" had "every power you haven't thought of". Literally; to fight her, you had to start shouting power names so she couldn't use them.
** Gives you a bit of fridge logic as to why declaring 'the power to have every power I haven't thought of' wouldn't eliminate the power and render her powerless since she can't have any power you've thought of and her root power is told to you.
*** Or just rattle off this short list: "The power to breathe underwater. The power to breathe in space. The power to breathe in an atmosphere. The power to survive without breathing."
* Inverted in an arc of ''Comicbook/{{Exiles}}'' in which the team arrives on an [[AlternateUniverse Earth where the Skrulls have ruled since the 19th century]], and several of them are thrown into a gladiator arena to fight other superpowered beings. Mimic, a mutant with the power to copy and hold onto the abilities of up to five other mutants, strikingly showcases "all four" of his various powers as he fights his way to higher tiers of the arena, until he finally comes up against "The Champion", that universe's version of ComicBook/CaptainAmerica. The Skrulls are expecting an epic fight, when Mimic ends it in ten seconds by letting loose optic blasts he copied from the ComicBook/XMen's Cyclops. The reader knows he has this power (if he's been paying attention, since Mimic had been using it since the start of the series), but the audience is shocked.
* While not powers, per se, Franchise/{{Batman}} seems to always have [[WhereDoesHeGetAllThoseWonderfulToys that one thing in his utility belt that saves the day]], despite there never being mention of it before. This was especially true in UsefulNotes/{{the Silver Age|of Comic Books}}, on [[Series/{{Batman}} the TV Show]] (shark-repellent bat-spray), and on the {{WesternAnimation/Superfriends}} ("You're a mouse? I'll put you in the bat belt mouse compartment!"). Fans have come to expect him to have all sorts of basic toys there (as well as a chunk of kryptonite in a lead-lined pouch because you can't be too careful), and the better writers either have him specifically preparing for a fight or have him {{MacGyver|ing}} a solution out of things you would expect him to have.
** In one episode of the TV show, the villains finally wised up and took away his utility belt (they couldn't [[JustEatGilligan just kill him]] because they needed him to ... extract musk from some weasels). So he asked for a couple of glasses of warm water, this being somehow essential to the musk-extraction process ... and proceeded to pull out ''dehydrated Bat-utility belt capsules'' from somwehere and reconstitute them.
** The writers have also shown that Batman, down in the Batcave, has a set of dossier folders on every single hero and villain on the planet, with detailed plans on how to take down each and every one of them if he ever needed to. This even includes the really, really stupid villains for whom the plan ought to be "oh just kick his ass already."
** The movies have their share of oddly specific and convenient gadgets, too, such as:
*** The Bat-Stop-The-Guy-About-To-Drop-Kick-Me-Arm-Apparatus from the 1989 film.
*** The Bat-Ice-Skates and Bat-Heaters from ''Film/BatmanAndRobin.''
*** The Bat-Van-Cutter from ''Film/TheDarkKnight''.
** In addition to his gadgets, Batman has whatever skills will be needed to solve the problem. And those skills have added up over the years to the point where he's [[MasterOfAll an expert at literally every skill imaginable.]]
* Captain Everything from ''ComicBook/{{normalman}}'' was the most powerful being on the planet Levram simply because he could defy all laws of physics, exhibiting a new power at every plot twist. Of course, this is just one of the ways in which he's a parody of Superman. He was also a complete moron, who forgot that he could fly ''while in midflight''.
* Also from Franchise/TheDCU, Infinity Man had the ill-explained power to bend all natural laws. He can modify the atomic structure of things. Good.
* ComicBook/ResurrectionMan's powers are ''literally'' dictated by the plot; anytime he dies, he'll come back immediately possessing some power that would have allowed him to survive what killed him. Drop him off a cliff, now he can fly, shoot him, now he's bulletproof, etc.
** New Spider-Man foe The Freak has the same ability.
** As does Doomsday, the only monster to ever kill Superman- except he develops new abilities that counter anything that harms him. At one point, he develops bony ear coverings to counter a powerful sonic gun.
*** Until he is finally undone by the one thing that he evolved that made him weak: Sentience.
--> '''Superman:''' You're different now. You can think for yourself. So think about this. Before, you were a mindless thing. Nothing could hurt you. You couldn't feel pain, much less understand it. But once you have felt it — it changes you — forever. And you'll begin to understand something new. Fear. I've lived with it all my life. You don't want to die again, do you? The agony of what's happened to you affects your speed — your strength... and that little bit of doubt — that you cannot win today — grows.
** Doomsday's power could be summarized as, each time he dies and comes back, his overall strength and power increase AND he's made immediately and instantaneously invulnerable to and has the capacity to kill or destroy whatever it was that killed him. He doesn't ''have'' to die, though: we once see him bashing his way out of a metal box he'd been contained in; his fists grow bony protection and eventually spikes with each punch. He's ''constantly'' spawning the fix for whatever challenge lies in his path.
* ''Comicbook/DialHForHero'' is based around a mysterious dial that enables an ordinary person to become a superhero for a short time, by selecting the letters H-E-R-O in order. Each time it is used, the dial causes its possessor to become a superhero with a different name, costume, and powers. The twist here was that the hero usually didn't get a power that would solve whatever problem he was facing in the most obvious and direct way. The trope was played straight, though, in that the power always turned out to be useful for the current situation, even if ''how'' it could be useful wasn't apparent at first. The basic plot of a Dial H For Hero story can be summed up as "figure out how being a human slinky helps you put out a forest fire."
* In the children's comic ''Korgi,'' the magic korgi spontaneously develops the ability to breathe fire.
** Ivy suddenly reveals that she has wings a la ''Film/TheDarkCrystal''. These sudden powers are perhaps more jarring because the main story has no dialog whatsoever, and the only indication that the korgis are magical comes from the introduction - we're never given any hint as to ''how'' this magic manifests.
* ''ComicBook/{{Darkhawk}}'' is an interesting variant on this trope, in the sense that Chris Powell [[HowdoIshotWeb didn't get an instruction manual along with the fancy amulet that transforms him into Darkhawk]], so he ended up discovering many of his powers by trial and error, most notably in reacting to new and stressful situations.
* The ComicBook/NewWarriors had an enemy/ally named Helix, who adapted to '''any''' threat against his body, be it disease, telekinesis, spider webs, or a beat down from [[FlyingBrick multiple super sonic flying, nigh invulnerable, super strong enemies]]. As soon as he was out of range from whatever threatened him, his body dropped whatever adaptations it developed.
* The DC villain Paragon has the power to mimic the superpowers of any superhero near to him. But he can also add a twist the originator cannot perform, so he thinks he is superior because he can use any power better.
* In a non-superheroic example, Thorn from ''ComicBook/{{Bone}}'' displays more and more ludicrous powers as the plot goes on, everything from simple PsychicDreamsForEveryone to seeing invisible ghost circles to super-strength to ''flight''. This is because her "true" power is power over ''dreams'', and the awakening of the BigBad is bringing the Waking World and the Dreaming closer together.
* The Engineer from ''ComicBook/TheAuthority'' is a repeat offender here. Her "powers" are derived from the [[AppliedPhlebotinum "nine pints of liquid machinery"]] that was developed from a combination of her own research and that of another genius and with which she replaced her blood. It basically means she can create virtually any device she can conceive of on the fly. However, while originally this seemed to be limited to what she could shape out of the actual nanoblood, the scope kept increasing until she could eventually build even very large constructs on-demand, as well [[SelfDuplication create duplicates of herself]] that shared her abilities. The only limit being how many different things she could mentally multitask at one time.
** Seth, the ridiculously powerful metahuman sent to kill and otherwise maim the members of ''ComicBook/TheAuthority'', might as well be a walking [[ComboPlatterPowers superpowered cafeteria.]] Having been designed to take down the most powerful superhero team in the world, he is given just about every superpower that his creators can imagine, at one point stating that he has powers "that [his enemies] don't even have names for".
* ComicBook/TheMightyThor was explicitly intended to be the most powerful superhero in the Marvel Universe, and in the early days this seemed to mean "modeled after UsefulNotes/{{the Silver Age|of Comic Books}} Franchise/{{Superman}}." He whipped out abilities like time travel and even super-ventriloquism on occasion before his powers became more clearly defined. (Though he actually became more powerful ''after'' they stopped throwing in weird abilities; in his early adventures he didn't really demonstrate the "Class 100" strength and city-engulfing weather manipulation he's known for now.)
* A very '90s miniseries called ''The Psycho,'' by James Hudnall and Dan Brereton, is set in a world where people gain superpowers by taking [[PsychoSerum various drugs.]] At one point the title character develops the ability to breathe water-- or maybe he had it from the start; after all, there's no way of knowing until someone's trapped you in a flooded room...
* The eponymous Comicbook/{{Empowered}} has on at least three occasions demonstrated powers she had no idea her suit possessed: Clinging, surviving in space, and very possibly flight. She's not aware of the third.
** Given an interesting twist, in that many times, they are Chekov's guns. She discovers the new power at the BEGINNING of the issue, points out how useless it is, and then uses it LATER to great effect. Another one? Her suit can turn invisible. Not turn HER invisible. The suit ITSELF turns invisible.
* The female ''Comicbook/GreenLantern'' character Arisia, a one-time fling of Hal Jordan's, was thought to have perished. She was found years later (somewhat randomly) on the planet Biot in a pod. We were then told that Arisia's species can go into a deep state of mental and physical hibernation while only ''appearing'' dead. All this was done so Geoff Johns could put Arisia into the ''Green Lantern Corp'' ongoing. Not the most elegant way of bringing someone back to life.
* Hawk and Dove. Holy crap, Hawk and Dove. Geoff Johns likes them so much that one of them will just have whatever powers they need for the plot to work. Army of unstoppable zombies? Well hey, Dove just happens to have an anti zombie laser inside her. Boyfriend dies? Dove can totally hear ghosts all of the sudden. Dove's in trouble? Hawk just happens to have the ability to sense when Dove's using her powers even though he's never had that power before. Sigh.
* NICOLE of the ''[[ComicBook/ArchieComicsSonicTheHedgehog Sonic the Hedgehog]]'' Archie comic series (and to a lesser extent, the ''WesternAnimation/SonicSatAM'' animated series), a small handheld device with utilities ranging from a translator, laser device, a protective forcefield and a scanner that can devise info and history from almost any object or area. In later issues NICOLE was evolved into the powerstation for New Mobotropolis from which [[GodModeSue she can transport or materialize almost any entity to the heroes' convenience]], though at least by this point her multiple powers are becoming less of a surprise.
** Sonic's "Super Peel-Out" maneuver became this in the early comics. In ''VideoGame/SonicCD'', the Super Peel-Out was nothing more than a way to get Sonic to reach high speeds without being a ball. In the comics, it was used for other methods, including limited flight and the ability to deflect attacks.
* Spoofed in ''ComicBook/TomorrowStories'' with Splash Brannigan. "He followed them into the painting! I didn't know four dimensional ink could do that!" "Well duh! It can probably do whatever story purposes require."
* At the end of the [[Series/BuffyTheVampireSlayer Buffy Season 8]] comics, Buffy gets new powers like flying and super speed due to [[spoiler:Twilight]].
* ''Herbie The Fat Fury'' got various superpowers from eating lollipops. These powers could be literally anything, from invulnerability and super-strength to hypnotism, talking to animals, time travel, and knocking out uncooperative indian chiefs.
* The Molecule Man, a ComicBook/FantasticFour villain can control molecules, so he can do just about anything, but he's not the brightest bulb in the shed and not completely evil, so he's often beaten before he can really use his imagination.
* Marvel's ComicBook/DoctorStrange makes even Silver Age Superman look downright consistent by comparison. One week he might say it's impossible to change the past, the next week he might casually rewind time by twirling his little finger and prevent the villain from ever being born. At his worst, it was less a case of him getting new powers as the plot demands, but more a case of him being able to do absolutely anything, ''unless the plot specifically required that he couldn't.'' This is probably one of the major reasons why the writers eventually stripped him of his Sorcerer Supreme title and most of his power.
* In [[EarlyInstallmentWeirdness early issues]] of Marvel's ComicBook/FantasticFour, the Human Torch would often demonstrate seemingly random new powers all the time. Although all of them were (at least thematically) linked to his ability to control heat and fire, many of them made little sense (some examples include ''sonar heat waves'', creating a lasso made only ''partially'' out of fire that could pick up paper objects without burning them, and the ability to surround an object with a coating of fire that could detect and react to someone's ''human aura'' in order to guide the object to them.)
* Eobard Thawne, the Reverse-Flash, after the events of ''ComicBook/TheFlash: Rebirth''. Suddenly powered by an inexplicable thing called the "Negative Speed Force", he now has the ability to travel back in time at will and change history. He also gained gained Reverse-Flash II's ability to create a sonic boom when he snaps his fingers, something his Speed Force should negate (otherwise every step he takes should do that). He can also... reverse-age himself? What?
* GoldenAge hero Comicbook/StardustTheSuperwizard's powers are never clearly defined, other than his "tubular spacial" which he uses to fly, but mostly consist of whatever the author thinks would be cool at that moment.

[[folder:Comic Strips]]
* ''ComicStrip/PhoebeAndHerUnicorn'' feature several unicorns who respond with "Unicorn!" in answer to any question about a new ability or even an unusual behavior, even if it's something as mundane as [[http://www.gocomics.com/phoebe-and-her-unicorn/2015/03/06 eating grass]] or [[http://www.gocomics.com/phoebe-and-her-unicorn/2013/07/19 getting trapped in playground equipment]]. Marigold gets a little put out if anyone tries to [[http://www.gocomics.com/phoebe-and-her-unicorn/2015/01/07 cut into her action]].

[[folder:Fan Works]]
* ''WebVideo/UltraFastPony'' uses this as a punchline. Thanks to the [[AbridgedSeries abridging process]], all of the canon foreshadowing about the powers of the Elements of Harmony gets left on the cutting room floor. So when it comes time to use those powers:
-->'''Twilight:''' Vaguely established magical friend powers, activate!\\
'''Night Moon Mare:''' What the heck is that?\\
'''Twilight:''' It's a {{plot hole}}. Deal with it!
* In ''ThirtyHs'', Franchise/HarryPotter is given a wide variety of powers he never had in canon, including groinsaws, the ability to punch astral vampires in half, the ability to summon holy fuck fire and meteors with his guitar fuck slayer, and the ability to see subatomic particles by squinting.
* Creator/UltamiteNineball's infamous fic ''Fanfic/{{soulless shell}}'' chronicles the adventures of [[GodModeSue Leif Melyamos]], who develops the ability to shoot FrickinLaserBeams, teleport at will, and outfight any opponent [[WaifFu at the age of about three]]. By the time he's eighteen, he can take on a bizarre OneWingedAngel form with horns and wings, and by the time the story comes to a [[NoEnding very abrupt stop]], has got hold of a sapient blood-drinking sword. Keep in mind this fic was put in the ''{{Literature/Redwall}}'' section, and said canon is supposed to have ''[[{{Demythtification}} no magic whatsoever]]'' (bar the occasional prophecies and InstantExpert routines). This fic is in fact a prequel to another fic entitled "Blood omen" (No, not [[VideoGame/LegacyOfKain that one]]), in which Leif's descendant Zain is an even better example, literally developing a new power with each fight scene.
* Fan fiction of ''Literature/TheLordOfTheRings''
** ''FanFic/LegolasByLaura'' depicts Gandalf as being able to fight Sauron to a standstill and [[CallOnMe teleport Frodo, Sam, Merry, and Pippin from the Shire to Mordor simply by wishing it]]. If he could do that, why did Tolkien need three books to get them there?
** ''FanFic/MagnoliaCinderellaCupcake'' has her [[TrappedInAnotherWorld fall into Middle-earth]], where she is "the most desirable lady ever" and has new powers. She uses each power once and then forgets it. Some of these are EyeBeams, SuperStrength and SuperSpeed.
* ''[[http://www.fanfiction.net/s/3247454/14/The_Adventures_of_Kitty_Pryde The Adventures of Kitty Pryde]]'' by Melodyrider (a series written as an ongoing companion comic to the Creator/JossWhedon run on ''[[ComicBook/XMen Astonishing X-Men]]'') has this chapter where Kitty, Colossus and X-Factor take on a misguided future version of Kitty, who, while not having any new powers, was able to apply her powers in new ways that Kitty hadn't considered before, including phasing through dimensions, sending bioshocks of people who she phases through and [[{{Invisibility}} phasing through light]].
* In a Bleach Fanfiction Wiki, [[http://bleachfanfiction.wikia.com/wiki/Miharu_%22Mihara%22_Kurosaki Miharu Kurosaki's]] Zanpakutou is quite possibly the embodiment of this trope, creating anything or having any given effect the wielder (or in this case, the creator of the character) imagines. It's command is even "Improvise".
* ''FanFic/TheSubspaceEmissarysWorldsConquest'' has an interesting non-AssPull version. The main characters get new powers depending on what world they're in.
* Marrissa Roberts from ''FanFic/{{ITS MY LIFE}}!''. Her powers include electric fight abilities, [[BatmanCanBreatheInSpace being able to fly to and breathe in space]], MEGA PAWNCH, "nerotksin" immunity, a super detective power and being able to materialize stuff out of nowhere.
* ''FanFic/LightAndDarkTheAdventuresOfDarkYagami'' adds new "Notes" whenever the plot demands. In addition to the Manga/DeathNote, we have the Royal Death Note, the [[BackFromTheDead Life Note]], the [[KilledOffForReal Anti-Life Note]], the Teleport Note, the [[TimeTravel Time Note]], the Ghost Note, and the [[RealityWarper Everything Note]].
* ''FanFic/MiTruLov'' sees Russia gain earth powers. If that wasn't enough, Kawaiilyn suddenly gains the ability to manipulate [[spoiler:earth, water, fire and lightning ''as well as'' air]] the second she needs them.
* In ''Fanfic/YoungOffender'', [[Manga/{{Cyborg 009}} 001's]] PsychicPowers are constantly evolving, and he often discovers new talents right when they're needed. However, this doesn't help Ivan's mental stability at all; he's particularly terrified that his powers might eventually drive him mad, just as they did [[spoiler:his aunt Katarina]]. His potential also terrifies ''his own teammates'', and to make matters worse? [[spoiler:Katarina confirmed that he ''will'' develop the same powers that drove her insane, though she believes he might be able to control them ''if'' he doesn't give in to the desire to change the future.]]
* Rose Potter in ''The Girl Who Lived'' has a tendency to get random superpowers and spells for no reason, solely for the purpose of making her seem "cooler."
* In the cancelled ''My Little Pony: Friendship is Magic'' meta-fanfiction ''Fanfic/{{Human}}'', the titular charater, Lord Second, is almost the embodiment of this trope, being internally aware of concepts like Dramatic Convenience, In-Universe Explanations, and Off-Screen Teleportation. At one point, he gains a healing factor simply by verbally acknowledging the offscreen healing that occurs between plots. He is also able to leap across entire cities at once, and will be literally ''forced'' by the story to dodge any physical attack, except ones by main characters. Also, at one point, [[spoiler:his son manages to circumvent this by training Princess Celestia to [[AscendedExtra become a main character.]]]]
* Link in the [[VideoGame/TheLegendOfZelda Legend of Zelda]] fanfic, ''FanFic/ZeldasHonor'', can [[spoiler: summon up horses, bows, torches and just about anything else as the plot demands]] because of his [[spoiler: Nevachrean heritage]]. He also can defy [[spoiler: death by an eleventh hour appearance of Navi]]. Can't beat the villain with the powers he has now? No problem! Just [[spoiler: put on the Fierce Deity Mask that you just recently restored using the innate temporary healing powers from the newly reawakened Triforce of Courage within you and due to the new Hylia like qualities Navi bestowed upon you, become a righteous god of terrible power]]!
* Actually sort of Paul's powerset in ''Fanfic/TheKeysStandAlone'', though hints of it were given in ''Fanfic/WithStringsAttached''. He develops so many new powers that Ringo describes it as gaining a new power every time he blows his nose.

[[folder:Films -- Animation]]
* Lampshaded and played for laughs in ''Film/WhoFramedRogerRabbit?'', Roger Rabbit meta-explains his ability to escape his handcuffs easily, when he left them to help stabilize the table as Eddie Valiant was trying to saw them off.
-->'''Eddie Valiant:''' You mean you could've taken your hand out of that cuff ''at any time''?!\\
'''Roger Rabbit:''' NO! Not at any time -- only when it was ''[[RuleOfFunny funny]]''.
* At the climax of ''WesternAnimation/KuboAndTheTwoStrings'', Kubo gains the ability to [[spoiler:turn the BigBad human and erase his memories]] with his [[MagicMusic shamisen]]. How he was able to suddenly do this with an instrument he used only to [[PaperMaster animate paper]] for most of the film is never explained.

[[folder:Films -- Live-Action]]
* The Heisei ''Franchise/{{Gamera}}'' series deconstructed this trope completely. Gamera reveals in [[Film/Gamera2AdventOfLegion the second film]] to have a "[[WaveMotionGun Mana Cannon]]" that obliterates the enemy of that film. It is learned in [[Film/Gamera3AwakeningOfIrys the final film]] that using that attack drained the Earth of its health, and [[GaiasVengeance releasing a hoard of Gyaos upon the planet]]. It is also learned that Gamera [[FriendToAllChildren bonded with humans]] in order to gain the [[ComboPlatterPowers ability to mutate and get new powers]] such as the Mana Cannon and Flame Absorbing powers -- but the Mana Cannon cost him that connection to humanity as well! This causes him to ignore Property Damage as he hunts the Gyaos.
* ''Franchise/{{Godzilla}}'' most famous examples would have to be [[Film/GodzillaVsMegalon his gravity-defying drop kick]], and his sudden ability to ''fly'' at the end of ''Film/GodzillaVsHedorah'' by curling up his body and firing his atomic breath backward so he shoots through the air like a rocket. Additionally, Godzilla developed magnetic powers to get the upper hand in the climactic battle of ''Film/GodzillaVsMechagodzilla''.
* In ''Film/JasonGoesToHellTheFinalFriday'' Jason is ambushed by the FBI which leaves his body completely obliterated, forcing his heart to evolve into a small creature that can hypnotize and possess people.
* Once Neo realizes he's "The One" in ''Film/TheMatrix'', he can pretty much do anything, which is [[strike:exacerbated]] played down in the sequels -- presumably the writers realized that having a RealityWarper who could kill the bad guys with a thought would kill any kind of dramatic tension. Of course, this leads to [[FridgeLogic problems]] [[BoringInvincibleHero of its own...]]
* [=R2D2=] in ''Franchise/StarWars'' manages to do just about anything when the plot requires, especially in the prequels. Like fly.
** The Force itself is this. The Force is apparently able to do anything from seeing the future, to shooting lighting from the hands, to changing creatures into grotesque monstrosities, and so on, whatever's required for the plot of the week. What keeps the Force out of StoryBreakerPower territory is that many powers seem to be unique or rare enough that only a few Force Users are actually able to use them, Force Users tend to neglect to use powers when they probably should, and that the Force is pretty fickle about if and when it'll let a Force User access its powers.
* ''[[http://www.imdb.com/title/tt0080931/ Nightmare City]]'', a low budget Italian flick where protagonist Dean Miller has a touch of Commando Concentrate™ (Just add weapons!). A news reporter with no combat training magically knows how to make functional firebombs and handle a sub-machine gun.
* The ''Film/{{Superman}}'' movies were even worse than the comics with this. The movies introduced:
** The most infamous new power, from ''Film/SupermanIVTheQuestForPeace'', "Rebuild-the-Great-Wall-of-China Vision". This one is especially egregious considering that Superman could have rebuilt it using his existing powers of flight, super speed and heat vision.
** The "Saran-wrap-S-shield" in ''Film/SupermanII''.
** Superman's memory-wiping kiss.
** Kryptonians suddenly also have the ability to teleport/blink at will, and shoot kinetic beams from their hands in ''Superman II'' as well.
** Flying around the world backwards to reverse time, though some consider this a visual metaphor taken too literally. Superman ''could'' and did travel through time in the comics by flying faster than the speed of light; apparently in the movie we're seeing this from his point of view, rather than him physically causing the earth to spin backwards and this somehow causing time to reverse.
* Considering all of the above examples, it comes as a surprise that 1984's ''Film/{{Supergirl}}'', Kara is able to [[ChangingClothesIsAFreeAction change her clothes and hair color]] by walking behind a tree. She can also shoot EyeBeams that make flowers grow.
* Horribly abused in ''Film/MidnightMovie''. Try to escape through a window or door? The killer makes them impenetrable. Try to call for help? He disrupts phones. Try to get the attention of someone on the outside? He makes it so no one can see or hear you. All that, combined with him being MadeOfIron, being able to teleport, and being able to find people wherever they hide due to literally sensing fear and you've got one of the most unfair SlasherMovie villains in history.
* Grandpa Seth in ''Film/{{Troll 2}}'' can do pretty much whatever he feels like, by virtue of being dead. Although the ability to stop time he showed at the beginning of the movie would have been very useful later on, to say the least.
* Iron Man's previously unmentioned [[spoiler: one-use lasers that he used to finish off the Hammer Drones]] in ''Film/IronMan2''.
** Completely justified, given that Tony Stark is constantly tinkering with and [[strike:upgrading his suit]] building new models of his suit. By the end of ''Film/IronMan3'', he's at Mark XLII (42). [[spoiler:And he keeps every single version, which comes in handy when he has to call them to fight completely autonomously in a battle with Aldrich Killian.]]
* In ''Film/GuardiansOfTheGalaxy'', Star-Lord and his team crash into the Dark Aster to stop Ronan the Accuser from destroying Xandar with the Infinity Stone. While they're in a dark hallway, Groot puts out glowing spores to light the way. Drax asks when he was able to do that.
--> Star Lord: Pretty sure the answer is "I Am Groot."
* The hero of ''Film/PumaMan'' has a number of [[ComboPlatterPowers random seeming powers]] such as flight, jumping around really high like an idiot while his [[HypercompetentSidekick sidekick]] does the fighting for him, teleportation, super strong and sharp claws, superstrength and the ability to go into a deathlike trance. (The Puma Man has the powers [[ShapedLikeItself "of a Puma Man"]], rather than them being derived from actual puma abilities. This essentially gave him whatever powers the writers needed to continue the script.)
* Near the end of ''[[Literature/{{Twilight}} Breaking Dawn]]'', Alice has a vision of [[spoiler:a massive battle with the Cullens and their allies on one side, and the Volturi on the other]] that involves the shapeshifters and Renesmee. This is despite the fact that she's supposed to be ''incapable'' of having visions involving shapeshifters and/or half-vampires.
* In ''Film/XMenDaysOfFuturePast'', Comicbook/KittyPryde now somehow has the ability to send people's consciousnesses back through time. (In the comic books, it was done by telepath Rachel Summers, daughter of Comicbook/{{Cyclops}} and Comicbook/JeanGrey. In the comics, it was ''Kitty'' who got Series/{{Quantum Leap}}ed into her past self; letting her be the sender allowed her to do more even though it's [[SpotlightStealingSquad naturally]] [[WolverinePublicity Wolverine]] who travels. It's still clearly this trope, though, as intangibility has nothing to do with sending a consciousness back in time, and we're not given any idea of how she can suddenly do this.)
* In ''Film/CaptainAmericaCivilWar'', Comicbook/AntMan displays the ability to transform into the collossal Giant-Man, something he couldn't do in [[Film/AntMan his own movie]]. Slightly offset by this power at least being logically connected to his existing abilities, and [[TropesAreNotBad Giant-Man's fight scene being considered one of the best parts of the movie]].

* Parodied in Creator/MichaelChabon's ''Literature/TheAmazingAdventuresOfKavalierAndClay'', in which our heroes create a comic strip character, The Escapist, just before the start of World War II. He begins as a detective-escapologist character. By the later years of the war, he's pulling tanks apart with his bare hands.
* Happens to nearly every plot-relevant magician in Raymond E. Feist's ''Literature/TheRiftwarCycle'' at some point or other. The meta main character, Pug, seems to experience as much of his development by being forced into new powers by circumstance as by study and learning. Nakor also exhibits this frequently later in the series, though it's implied that he has known his new 'tricks' for a long time and simply did not choose to use them for whatever reason.
* ''Literature/AnitaBlake'' is the best example of this ever, having morphed from a simple animator/necromancer in the book series to... frankly, this editor lost track of them all a long time ago. But in pretty much every big confrontation, she gets a new Power of the Month.
** These days, they all require her to [[DeusSexMachina have sex to activate]].
** In every single book, Anita pulls a new power out of her ass, spends a bit in the hospital from "overdoing it", and from then on can use the power whenever.
* [[Literature/DoraWilkSeries Dora Wilk]] has been given new powers every book, going from [[WitchSpecies half north witch - half fertility witch]] who sometimes [[DreamingOfThingsToCome sees things]] to wielding powerful magic, forming mind-bond with angel and demon and having two vampires [[spoiler:and an entire werewolf clan]] at her disposal - all appearing when necessary. Her best angel friend Joshua gains ability to Manifest just in time to save Dora [[spoiler:and then ability to heal - again, to save Dora]] and Miron gets [[spoiler: fire powers ]] right before he really needs its RequiredSecondaryPowers. This has caused some negative feedback among fans, as they start to have a feeling that instead of coming with clever solution to a given problem, the author just throws in yet another superpower.
* Princess Merry in Laurell K. Hamilton's [[Literature/MerryGentry other main novel line]] is just like Anita Blake. Starts out as having only a slightly extended lifespan and the ability to craft glamours (illusions) around herself to alter her appearance, making her effectively human in power level. Then she gains the power to turn someone inside out by touching them. Then in the second book she gains the power to make someone bleed to death in a matter of seconds out of any cut, no matter how small. Then, [[AuthorAppeal because it's a Laurell K. Hamilton novel]], she gains the power to give anyone who [[DeusSexMachina has sex with her]] major mojo. Then she gains more random stuff for herself that's typically forgotten by the next book.
* In the second book of the ''Literature/NightWatch'' series, we are introduced to a character called "the Mirror", who is capable of becoming more powerful and acquiring complex magical abilities in order to match whatever situation he is facing at the time. It is justified due to the fact that a Mirror is formed from the magical Twilight for the specific purpose of redressing imbalances in the power structure of the magical Others, and once that goal is accomplished, it ceases to exist.
* The resolution of the Literature/TelzeyAmberdon story "Resident Witch", by Creator/JamesHSchmitz, relies on Telzey's psychic powers including the ability to BodySurf, despite no previous indication that she could do this.
** In another story, Telzey has to do some lengthy cross-country running. We're suddenly told that she "liked a lot of sports and played hard at them" (despite carrying a full course load at university plus her psi spy work) and could do this with ease. This is the same story in which she does file management on the villain's mind, to erase half of it, rendering him harmless. Why she did not do this when he first started menacing her is not explained.
* ''Literature/TheHeroesOfOlympus'' has this on a series level, not within the series. Apparently certain children of Hephaestus can wield fire, and all children of Aphrodite have apparently always been able to speak French, and some can charm-speak people into doing what they want.
* Richard Rahl from ''Literature/TheSwordOfTruth'' falls victim to this trope fairly regularly. Understandable, since he's also subjected to OnlyTheAuthorCanSaveThemNow at least once a book.
** There's also the convenient twin features that nobody actually knows what his powers are or how to use them intentionally, and his powers always seem to activate instinctively when he really, really needs them. He eventually finds a book the should tell him how his powers work... but cannot read it at the time because he's been depowered (it's established early on that there are magical trip mines in magic books that erase the memory of the contents from the mind of anyone who really shouldn't read that particular book).
* The whole Flock in ''The Final Warning'', the fourth ''Literature/MaximumRide'' book, and Angel throughout the series. ''All'' of the flock get this throughout the series, it was just not until that point that Creator/JamesPatterson threw up his hands and decided that they were uncontrollably mutating which would cause them to develop random, unplanned powers.
* Daniel in ''Literature/DanielX'' by Creator/JamesPatterson. Almost every chapter he gets a new power. He can create people from thin air, control animals, turn into animals, create different scenes(like turn a messy room into a clean room), has an internal iPod, and is incredibly intelligent. And this is just the first book.
* Dwarves in ''Literature/ArtemisFowl'' get a new ability every book. They can tunnel by eating through earth, [[{{Fartillery}} fire a devastating barrage of digested rocks/mud/whatever they just dug through]], propel themselves underwater and ignore the bends because of intestinal bacteria, have saliva that works as a healing balm, can cling to walls if dehydrated, have glow-in-the-dark spit, which can also solidify to trap enemies, have prehensile beards/antennae (very handy lockpicks/emergency automatic surgical needles).
** In ''The Atlantis Complex'', they can now expel 1/3 of their body weight out of their rears as a sort of jet-assisted escape. It's stated that this is a natural reaction to life-or-death situations.
* The ''Literature/DragonridersOfPern'' books are guilty of this when, in the 2001 book ''The Skies of Pern'', the characters suddenly discover the {{foreshadow}}ed power of telekinesis when the book's protagonist's dragon buddy gets attacked by giant cats (and [[spoiler:when they discover that by getting rid of the Red Star and Thread, it opens up Pern for bombardment by meteors]]).
** Menolly in the Harper Hall subseries has a bit of this in the second book. When she and a couple of friends are menaced by the AlphaBitch and her boyfriend [[AppropriateName Benis]], she decks said boyfriend -- who is quite a bit larger than she is -- with a right cross. We're not told where she learned this. Perhaps Anne was attempting GettingCrapPastTheRadar as a YA book at that time couldn't have the heroine kicking an assailant in the balls.
* The Ohmsfords, main characters in some of Terry Brooks' ''Literature/{{Shannara}}'' books, run on this. Fair enough, their power is [[ExactlyWhatItSaysOnTheTin actually called]] "The Wishsong," but it means the plot follows a hundred iterations of "Boy he's screwed," ... "but ''suddenly'' the song asserts itself and does whatever he needs!"
%% * Zoey from ''Literature/TheHouseOfNight'' and in later books, [[spoiler: Stevie Rae]]. To a degree, [[spoiler:Aphrodite]].
* In the ''Literature/MollyMoon'' series, Molly picks up a new power for each book. She starts out semi-plausible in the first book by learning how to hypnotize people, but from this basis power she begins learning other, increasingly exaggerated, powers: In the second, she learns how to stop time. In the third, she learns how to ''travel through'' time. In the fourth, the new power is mind-reading, and in the fifth, it's ''shapechanging.''
* In the Franchise/StarWarsExpandedUniverse, Luke Skywalker goes through this [[http://starwars.wikia.com/wiki/Luke_Skywalker#Force_powers to a certain degree]]. After several books, it became known in-universe that he is ludicrously powerful and can learn pretty much any Force-based skill [[InstantExpert very quickly]]. Many of these skills never come up again, or only when that same author writes him again.
** ''Literature/{{Allegiance}}'' has the spirit of Obi-Wan guiding Luke through discovering the unlock code for the room he's locked in.
** ''Rebel Force'': Luke is captured by someone who's developed a particularly nasty form of brainwashing, involving destroying someone's past and personality to make way for a new, loyal one. He escapes shackles by persuading them to stretch wide enough to let him pull his hands through but is put through the procedure anyway. To all appearances and instrumentation Luke is brainwashed, but thanks to the Force he is in fact completely unaffected. This power also keeps his morale up during the process.
** In ''Literature/SplinterOfTheMindsEye'', proximity to the [[AmplifierArtifact Force-boosting Kaiburr Crystal]] lets Luke [[BackupFromOtherworld channel Obi-Wan Kenobi to help him fight Darth Vader]], come BackFromTheDead, and heal Leia from the brink of death. Alas for him, the crystal only gave him such a power boost when in that particular temple on that particular planet.
** ComicBook/MarvelStarWars has some.
*** In ''The Empire Strikes'', Luke ends up [[AdventuresInComaland in a coma]] and is captured... and later his body fights free of restraints that should have held him when awake, finds his confiscated equipment, and fights off everyone who tries to stop him. While he was in a coma. He came out of the coma completely ignorant of what had transpired.
*** In ''Saber Clash'' while fighting Orman Tagge, a man who had had years more experience in the art of the lightsaber, Luke was initially at a severe disadvantage and almost died... but the Force then let him make a comeback that had him fighting without art or polish but with such skill and control that he was able to cut off Tagge's cyber-vision goggles, leaving him unhurt but a quivering, shocked wreck.
*** ''The Last Jedi'' has Luke calling on the Force to show him where his enemies are and how soon they'll reach him. The artist chose to portray this in a way visually similar to [[WesternAnimation/AvatarTheLastAirbender Toph sensing vibrations]], albeit more colorfully and rippling out from his head.
*** ''Hello, Bespin, Goodbye!'' has him [[http://scans-daily.dreamwidth.org/2926481.html find and detonate the primers]] to a number of bombs whose locations he does not actually know in a spectacular display of StuffBlowingUp... not the bombs themselves, just the primers.
** In ''Literature/ShadowsOfTheEmpire'', during a round of hand-to-hand combat against an {{Expy}} of a Franchise/{{Terminator}}, he discovers that he can use superspeed.
** In ''Literature/TheTruceAtBakura'', he can talk to the parasitic lungworms infesting his body, which will soon kill him, and persuade them to stop chewing on his tissues and crawl out of his mouth.
** In ''Literature/LukeSkywalkerAndTheShadowsOfMindor'', Luke is able to absorb blaster bolts without harm, communicate with meltmassif creatures that do not understand the concept of organic life, 'feed' said creatures so that they are forever free of the BigBad's control, and in a very trippy mind-battle, when the BigBad becomes a black hole and swallows him, he becomes a white fountain.
** ''Literature/TheCourtshipOfPrincessLeia'' has him casually root through Isolder's memories while the other mentions his past, and when they're falling he manages to slow the falls down.
** Literature/TheThrawnTrilogy, and Creator/TimothyZahn's work in general, gives him the ability to read someone's presence like a second face, picking up on emotional states and knowing if someone's had an idea, the ability to enhance his senses, plus a kind of short-term PhotographicMemory - he can rewind his short-term memories, within an hour or so, and recall with perfect accuracy things he wasn't paying attention to before. There is mention of him learning this from Yoda, at least.
** ''ComicBook/DarkEmpire'' grants him the power to make legions of droids self-destruct, the ability to generate dopplegangers, send two way visual/audio messages across great distances, and in the audio drama, the ability to fix hyperspace anomalies.
** In the ''Literature/JediAcademyTrilogy'', a prospective student won't come study with him until he's crossed a [[LethalLavaLand lake of lava]]. Half way across, Luke fights a creature living in the lava, which covers up the stones he's been hopping across. Not a problem! He extends the power he's been using to [[ConvectionSchmonvection defy convection]] and just walks across the surface. He's also able to invade peoples' minds to find if they're Force-Sensitive.
** In ''I, Jedi'' he has the ability to retrieve lost memories and damp down any of his senses.
** The ''Literature/BlackFleetCrisis'' gives him rather pointless ''super-architectural powers'' which would make anyone who's ever worked with stone white with envy. He goes to the beach where his father once had a fortress and finds only widely-scattered rocks.
---> "The sand around him stirred. The rocks shuddered, shifted, then began to rise from the sea and the sand as though sifted from them by an invisible screen. Swirling through the air as they sought their place, the stones took shape as broken wall and shattered foundation, as arch and gate and dome-the ruins of Darth Vader's fortress retreat.\\
It hung in the air around and above Luke as it had once stood atop the cliff, a dark-faced and forbidding edifice. [...] As he had redeemed and reclaimed his father, he would redeem and reclaim his father's house.\\
Now the stones swirled again in the air, joined by others plucked from the sea and stripped from the face of the cliff. Now broken edge fused against broken edge, and the dark faces of the rock lightened as their mineral structure was reshuffled. Now heavy rock walls and floors thinned to an airy elegance as if they were clay in a potter's press."
*** He then instantly builds a tower that is perfectly camouflaged with its surroundings, has the gravity act however he wants it to, and makes door and window holes open wherever and whenever he pleases. In lieu of furniture he tells a guest to sit and forms an "air cushion" under them.
** ''Literature/TheNewRebellion'' extends the heat-redirection power, letting Luke literally heat the hollow insides of some hostile acidic balloon-things until they burst.
* Tash Arranda of ''Literature/GalaxyOfFear'' is not Luke Skywalker, but she does have TheForce. From time to time during the series it [[SentientCosmicForce spontaneously helps her out]] by letting her grasp new powers, though her lack of training means [[HowDoIShotWeb she can't use most at will]]. Right from ''EatenAlive'' she gains the power to create a kind of personal DisruptorShield, though she can't hold it up for long. By ''Clones'' she can perform [[MindOverMatter minor telekinesis]] at will.
* Harry [[Literature/DresdenFiles Dresden]] has a fair amount of this going on, but all of it is rigorously justified. Some of it is off-screen, and he'll remark to various friends or to himself on why he made that Focus or practiced that skill. Demonreach would be an on-screen example, and so would [[spoiler: becoming the Winter Knight]], though [[spoiler: Mab]] has been predicting that he will do so because he will need to invoke this trope.
** The only seemingly-inexplicable examples were Hellfire and Soulfire, but those turned out to be justified.
* Justified in ''Villains Inc.'' (sequel to ''Literature/WearingTheCape'') when an encounter grants Astra the ability to sense magic, allowing her to make several observations key to the plot. It is suggested that this added power is temporary, however.
* In ''Literature/HarryPotterAndThePrisonerOfAzkaban'' Lupin repeatedly points out that the Patronus charm is incredibly advanced magic. He highlights that only very powerful wizards can pull it off, and that even fully qualified wizards struggle to master it. By ''Literature/HarryPotterAndTheOrderOfThePhoenix'', pretty much everyone in the narrative can cast a full corporeal Patronus without any trouble whatsoever, including most of the adolescent members of the DA (though Harry notes that they're doing it without the suffocating presence of Dementors, which make casting the spell harder). In the next book, Dumbledore uses his Patronus to send a message to Hagrid (the Patronus speaks with the caster's voice), and later books show Tonks, Kingsley and Arthur Weasley using that ability as well.
* Creator/MaxFrei's books run on this. Throughout the first books, Sir Max discovers a new magic skill in almost every chapter, making him essentially a CreatorsPet.
* A bit of subversion with Lionblaze from ''Literature/WarriorCats'', since his power covers the incredibly wide umbrella of "being ''really'' good at fighting", meaning the authors are able to make them take the shape of whatever they're in the mood for writing. What to show how crazy and out off control he is? He is [[NighInvulnerability invulnerable]], and bloodthirsty to the point where he bathes in his enemies' blood. Need something heavy held up? He has super strength. Bullet time is fun to write? He fights in bullet time.
* Literature/PrincessesOfThePizzaParlor: Defied, as said in the first novel:
--> You can't decide a few hours in that [your character] knows kung-fu or anything, just because it's convenient.
* Dr. Maracot from Arthur Conan Doyle's sci-fi classic, ''The Maracot Deep'', is introduced as one of the world's leading experts in marine biology. Then, about four fifths into the book, the narrator suddenly reveals that he's also an expert in ancient mythology, which happened to be what the plot needed at that point.

[[folder:Live-Action TV]]
* ''Series/{{Angel}}'': This happens to Cordelia in Season 4, after Jasmine seizes control of Cordy's body.
* This happened a couple times on the 1950's {{Superman}} TV series. Discussion above in the Comics section.
* [[TheSpock Spock]] was a master of this. In various episodes (and movies) of ''Franchise/StarTrek'', he suddenly demonstrated the abilities of mind-melding, the Vulcan nerve pinch, a light-protective nictating membrane, the ability to go into a deathlike trance at will, and a detachable soul that would allow him to later come back from the dead. Absolutely none of these were telegraphed before he absolutely needed them (as opposed to say, Wesley Crusher being told he had a great destiny by the Traveler long before he pulled the ability to stop time [[AssPull out of his ass]].) This, plus his refusal to admit that his parents were the ambassador and his wife or that he had to have sex with his wife or he'd die, make it ''almost'' plausible that as of ''Film/{{Star Trek V|The Final Frontier}}'' he could have had a long-lost half brother he never told anyone about. Almost.
* Seven of Nine on ''[[Series/StarTrekVoyager Voyager]]'' had Borg implants/nanoprobes that could allow her to do everything from sense otherwise-invisible aliens to ''raise the dead'' when required.
* ''Series/DoctorWho'':
** The series star is an alien with nebulously defined abilities. Oh, ''dear'':
*** The First Doctor started out with no powers. Season 3 introduces his special abilities - he is shown to be able to resist the effects of a time-destroying weapon that ages his companion to death, remember very long algorithmic sequences, control people using his life force, and hypnotise his companion (using [[HypnoPendulum fairly conventional hypnotism techniques]] and a RingOfPower). Season 4 introduced his superhuman physical robustness (allowing him to survive in the Antarctic) and his ability to regenerate, although at that point it was said by the Doctor to be 'part of the TARDIS'. (This last was a consequence of RealLifeWritesThePlot as Creator/WilliamHartnell was leaving the series and the writers had to come up with an AuthorsSavingThrow to keep the show going with a new lead actor in a way that made sense to viewers.)
*** The Second Doctor was told he was 'more than human' due to the effects of time travel itself, with Jamie's time traveller DNA being more valuable to the Daleks than the (then) non-travelling Victoria's. In "The Abominable Snowman" his telepathic abilities were increased to the level that he can mindmeld with Victoria, though the procedure is at this point very dangerous and can only be used if he absolutely has to. We also learned of his enhanced life span.
*** The idea of the Doctor having two hearts was not revealed until the first episode featuring the Third Doctor. Prior to this, there were several episodes explicitly indicating the Doctor had only one heart. The Third Doctor also [[SuddenlyAlwaysKnewThat suddenly knew martial arts]] and possessed strength greater than what he should have.
*** The Fourth Doctor reveals he has a "respiratory bypass system" in "Pyramids of Mars", meaning he can go for much longer without needing to breathe. He also now possesses telekinesis ("City of Death"), experiences sudden visions of the future ("The Deadly Assassin") and can hypnotise most people effortlessly just by [[HypnoticEyes getting them to look into his eyes]] (though to be fair, the Master had previously displayed a similar ability). He also picks up some bizarre, uselessly specific powers to get out of plot corners that will almost certainly never come up again - [[MakeMeWannaShout the ability to shatter windows with a shout]] ("The Power of Kroll"), the ability to breathe helium without it affecting his voice ("The Robots of Death") and the ability to shut down his body processes and go into a state of temporary biological death ("Shada"). Some ExpandedUniverse stories (e.g. ''The Death Pit'') even have him able to read anyone's mind without even trying if they're thinking loudly enough, and contemporary-to-the-series comics have him able to psychically detect his companion's pain to the point where the villain specifically tortures Sarah so her pain can send a signal to the Doctor. In "City of Death" he gains the implicit ability to ''fly'' for a gag - [[ForgotAboutHisPowers never used again, of course]]. [[CoconutSuperpowers Though almost certainly for the best.]]
*** In the second episode of the new series, the Ninth Doctor suddenly has the power to focus his mind and walk between the blades of a giant spinning fan. It can be interpreted as a LeapOfFaith, but would have been nice if he'd remembered he had this power before Jabe died... He also announces in his first episode that he could sense the turning of the planet, time itself and other kinds of information that he'd previously had bits of the TARDIS to inform him of.
*** In the first appearance of the Tenth Doctor, the Doctor gets his hand chopped off in a sword fight. Luckily he remembers that he has enhanced HealingFactor shortly after a regeneration and grows back his hand (to be fair, no previous Doctor had ever suffered a major injury immediately after regenerating - however the Eighth Doctor ''did'' display a healing factor when he was seen removing a tube from his chest soon after the change). He's able to use his mind-meld to selectively erase parts of someone's memory, and can tune into a single thought broadcasted by everyone on Earth via the Master's satellites and use it to de-age himself, dissolve his cage, levitate, form a shield bubble, and give him telekinesis. Another, particularly [[FridgeLogic glaring instance]] of this is in "Planet of the Ood", when the Doctor is able to sense the enslaved Oods' pain through their telepathic field, yet when he encountered them before in "The Impossible Planet"/"The Satan Pit" he made no mention of sensing their telepathic field [[spoiler:or the psychic entity powerful enough to possess multiple Ood and humans simultaneously, which you'd really think he'd be able to sense under the circumstances]]. He also claims to be able to sense the presence of other Time Lords, an ability decidedly absent during numerous previous occasions in which he was interacting with disguised Time Lords like the Master and Rani and none the wiser for it.
*** The Eleventh Doctor's first episode shows him able to think so fast that time appears to freeze while he perceives things in the area he shouldn't be able to hear or see, which never comes up again (though it may explain the fan thing the Ninth Doctor did.) In "The Lodger" the Eleventh Doctor headbutts [[spoiler:Craig]] to telepathically implant information about who the Doctor was and why people should take his advice, never used before or since, even when it would help a lot.
*** Similar to Eleven's ability to slow down time, the Twelfth Doctor has the ability to create a virtual TARDIS inside his mind in which he can reason out challenges before executing a plan, while also interacting with a memory of [[spoiler: his lost companion, Clara]]. His telepathic abilities now also include telekinesis, to the point where he is shown unlocking a door with his mind (even though this renders one of the major functions of the sonic screwdriver moot).
** The Doctor's use of this trope pales in comparison to his sonic screwdriver, which has thousands of settings and started off being used to ''put in screws''. A list of everything it has done would be as long as this page. The original series wrote it out as it was becoming omnipotent and the writers used it as a get-out-of-trouble-free card too much. TheMovie brought it back, and the new series imposed some definite restrictions on its abilities so as to have a reason ''not'' to let the Doctor use it to get out of anything. It's still pretty handy, though.
** [[RobotDog K-9]] was written out of the series after he acquired so many abilities that it was difficult to come up with plots that couldn't be resolved in a few minutes by K-9. Some episodes deliberately incapacitated K-9 to take him out of the story.
** The TARDIS in "Logopolis" suddenly grows a 'cloister bell' that sounds when the TARDIS itself is in danger of dying. It never sounded the bell when it was ten minutes away from tearing itself apart in "The Edge of Destruction".
*** The series regularly gives the TARDIS new abilities as the plot demands, to the point where it could have its own page.
** [[Characters/DoctorWhoRevivalSeriesCompanionsClaraOswald Clara Oswald]] has been accused of this from time to time, as one episode has her being a super-hacker, but the next says she has trouble using iPlayer (though this is explained in the plot as the former occurred while she was under the influence of a super-computer, but by the time of the latter that effect had worn off). One of the biggest examples cited by critics is actually, in reality, an aversion. In "Hell Bent", she is shown operating her own TARDIS without any problem, even though she had never been shown piloting the ship conventionally (though she once used her mind and on other occasion was able to actually ''ask the ship'' to do her bidding); however for longtime viewers this isn't a sudden ability as one of her very first episodes, "Journey to the Centre of the TARDIS", set a number of years before "Hell Bent" (possibly five or more due to a time jump the series has at one point) established that the Doctor was teaching her how to use the TARDIS and she is shown programming the console in the episode "The Zygon Inversion".
** Another companion, Romana, was a fellow Time Lord and when [[RealLifeWritesThePlot the role was recast]] after one season, she was shown to regenerate like the Doctor. However, her regeneration was treated comedically, with her "trying on" several different appearances before settling on one. The Doctor appears unfazed by this which lead to the assumption that female Time Lords have more control over their regenerations than males (a fact referenced obliquely during [[spoiler: River Song's regeneration]] in "Let's Kill Hitler").
** Susan, the Doctor's granddaughter, suddenly displayed telepathic abilities in the Season 1 storyline "The Sensorites", actually predating the Doctor demonstrating similar abilities. In her case, it was a one-off demonstration as she never did it again on screen; explained as being the result of being on the Sense Sphere.
* Series/{{Ultraman}}, Series/UltraSeven and the other ''Franchise/UltraSeries'' heroes are the kings of this. Though they have a set powers base, many develop and use one-shot energy attacks for specific monsters that are never seen again, or, even, completely pointless in the face of a pre-existing energy attack. And each time they would re-appear in another series, they'd only have the very basic forms of Ultraman powers they were known for. However, the worst offender is Ultraman Jack from ''Series/ReturnOfUltraman'', who has the Ultra Bracelet -- a weapon that can shapeshift into whatever is needed at the time: a shield, eye-slugger, blade, sword or Cross-Shaped Lance to stake an alien named Draculas.
* This happens to the ghosts from ''Series/GhostWhisperer'' a lot. Sometimes it gets a brief explanation. Usually not.
* ''Series/{{Smallville}}''
** Played with Clark Kent. Except for invulnerability, SuperSpeed and SuperStrength, all his others powers (X-ray vision, heat vision, super hearing, SuperBreath, in that order) come exactly as he needs them, although they are all established powers in the comics.
*** Played straight for [[spoiler:Telekinesis]] in "Crusade", [[spoiler:mind reading]] in "Echo" and [[spoiler:MindControl]] in "Persuasion". Apparently the Fortress of Solitude has ''many'' powers it can give Clark but the Jor-El AI doesn't want him to have too much too fast.
** Chloe Sullivan. She initially develops healing powers to heal ComicBook/LoisLane and then SuperIntelligence which manifests as a machine-like ability to run search algorithms in her head. Although it is later revealed Chloe didn't develop super-intelligence so much as [[spoiler:she gained it when Brainiac took up roost in her mind.]]
* ''Series/{{Heroes}}'' puts some interesting spins on this one:
** Several characters demonstrate the ability to acquire new powers from other powered people. Peter Petrelli copies them, Dad Petrelli takes them, and Sylar rips them out of their heads (killing them, and he gets to use Peter's copying power later).
** In general, the whole series operates this trope at a higher level. If the writers need a new power, they don't give it to an existing character, but introduce a new character with the desired ability. One of the benefits of LoadsAndLoadsOfCharacters is nobody much notices a few more or less.
*** Ando is a particular victim of this trope. His power goes from power amplification that happens to ''look'' like red lightning to [[spoiler:concussive blasts to tech manipulation to actual electricity]].
* ''Franchise/SuperSentai'' and its adaptation ''Franchise/PowerRangers'' have been known to dabble in this area, depending on the series. The later series tend to do this a lot more, as they need to introduce more weapons and mecha for the Rangers compared to the earlier ones.
** An interesting subversion occurs in ''Series/PowerRangersInSpace'', in which Andros has been carrying his own Battlizer for a good portion of the season, using it only to power up his attacks and control the Delta Megazord. Eventually Carlos asks him why he's never used the highest power setting on the device, to which Andros replies that he worries that it may be ''too'' powerful. Later, in a battle in which he is unable to morph, the final setting is activated and he becomes the Red Battlized Ranger for the first time. Mind you, Andros isn't the one who activated it--it was pressed by a little girl nearby. For all she knew, the setting ''was'' too powerful and it could have blown them all up.
** Conner in ''[[Series/PowerRangersDinoThunder Dino Thunder]]'' for example, is able to access his Battlizer for the first time ever by just...wishing for it I guess... Generally, more technological based teams are better about this, with new weapons and zords being built and tested prior to use. Dino Thunder has this as part of the premise: the power source itself is mysterious meteor fragments. More powers are unlocked as the series goes by, and using the raw power of the gems into a very strong blast comes along later still. The BigBad is finished off by being ''chomped by a dinosaur made of pure Dino Gem energy.'' However, that permanently depletes the Dino Gems (but of course, 'permanently' means 'until a ReunionShow demands their return.')
** ''Series/MahouSentaiMagiranger'' made extensive use of this trope; all one of the Magirangers had to do was demonstrate sufficient [[HeroicResolve courage]] or [[AnAesop learn an important lesson]], and they would be gifted with a new spell suited for whatever predicament they've found themselves in. [[JustifiedTrope Mind]], this was because the spells were being granted to them by the [[OurAngelsAreDifferent Heavenly Saints]], who were always watching over them. This carried over into ''Series/PowerRangersMysticForce'', a bit differently: a book called the Xenotome would reveal a spell whenever the rangers earned it, and their SuperMode was granted by the Tribunal of Magic (''roughly'' equivalent to the Saints; figures neutral to the Rangers vs. Underworld battle, far outranking the characters who had been Saints in Magiranger, but impressed by the Rangers' courage.) The Mystic Rangers were also often shown being taught magic by TheMentor and TheSixthRanger during downtime, so sometimes a new spell was introduced with no fanfare in situations where it's likely they learned it offscreen.
** ''Series/TensouSentaiGoseiger'' and its adaptation ''Series/PowerRangersMegaforce'': Whenever the narrative thinks the rangers learned the [[AnAesop Aesop Of The Week]], they gain a new set of Headers, which are items that can either combine with their weapons for more powerful attacks or enlarge to serve as a MechaExpansionPack.
** Anniversary series ''Series/KaizokuSentaiGokaiger'' has this trope as a recurring plotline. The Gokaigers are the 35th Sentai and need to learn to use the powers of the previous 34 Super Sentai teams in order to unlock the greatest treasure of the universe. Whenever a member of one of the previous teams deems the Gokaigers worthy, they will unlock a new power for them. This mostly happens when the Gokaigers show HeroicResolve against a particularly tough MonsterOfTheWeek or show another virtue associated with one of the older teams. The adaptation ''Series/PowerRangersSuperMegaforce'' plays this trope even straighter, by having the mentor Gosei randomly hand out new power ups or mecha whenever the rangers need them. A particularly ridiculous example is when he tells the rangers they suddenly gained the power to summon the Ninja Zord, despite the episode not featuring or even having anything to do with ninjas.
* Most ''Franchise/KamenRider'' shows have this trope. Like the Sentai and Power Rangers example above, the later series feature this more prominently compared to the older ones, since newer series feature more Riders, more weapons and/or more transformations, compared to the older series.
** The first one to get the ball rolling was ''Series/KamenRiderBlackRX'', which gave Kotaro two forms in the middle of the show, one gave him a CoolSword and the ability to turn into water, and the other [[TheGunslinger gave him a gun]].
** ''Series/KamenRiderKuuga'' and his various forms. It seemed that all he has to do is wish for a new ability, and [[TransformationTrinket the Kuuga Belt]] will give him a new ''form'' for that ability! How'd he get Dragon form? [[InASingleBound He needed to fly!]] How'd he get Pegasus form? [[TheGunslinger He needed a gun!]] How'd he get Titan form? [[MightyGlacier He needed to be stronger!]] How'd he get Ultimate form? ''[[UnstoppableRage He got really pissed off!]]'' But ''Kuuga'' actually subverts this trope as Yusuke needed to learn how his abilities worked (his initial fight using Dragon Form, before he knew it used a staff, was a NoHoldsBarredBeatdown ''against'' him, as he was finally able to ''reach'' the monster in Dragon Form but was weaker than his JackOfAllStats Mighty Form, while his first fight in Pegasus form overwhelmed his mind due to not being used to the SuperSenses it gave him). And second, in order to get his stronger forms he had to be shocked with a defibrillator. Also, these new forms were mentioned on a piece of ancient text, which, at the beginning of the series, could not be read by the protagonists, meaning Yusuke did not simply wish for them.
** A particularly egregious villain example happens in ''Series/KamenRiderFourze''. When Gamou is about to [[YouHaveFailedMe send Hayami to the Dark Nebula]] He [[ContrivedCoincidence conveniently]] gains his Supernova power, the Eye of Laplace. While every previous Supernova just turned a Horoscopes into a [[OneWingedAngel giant monster]], Hayami instead gains the power to see Zodiarts evolutions so he can just look at someone and instantly not only know if they can become a Horoscopes, but find people who are so compatible that just pressing the switch will instantly evolve them. In the 33 episodes before this, only 2 Horoscopes had evolved during the course of the show (5 were evolved before the series began). After this, a new Horoscope was introduced every 2 episodes. Without this power, there would be no way for the writers to possibly fit in the remaining 5 Horoscopes in the last 14 episodes.
** Multiple series (such as ''Fourze'', ''Wizard'', and ''Drive'') can run into this thanks to their MerchandiseDriven nature. The toylines involve little collectible trinkets that in-series provide powerups, so of course [[ProductPromotionParade each powerup needs to be shown off at least once]]. These series justify the powerups' presence by having a support character that can regularly provide new upgrades, but they can still run into this trope when the item in question is either too-conveniently key to beating the MonsterOfTheWeek or extremely situational yet too-conveniently manages to be helpful soon after it's introduced (and in either case, the support character is usually not in any position to actually tailor an upgrade for the situation, so no justification there). On the other hand, some powerups have zero plot importance and are used just for the sake of demonstrating for the audience; and the major [[SwissArmyHero form-changing]] items are always given appropriate buildup beforehand.
* Sookie from ''Series/TrueBlood'' has gained new abilities as well. [[spoiler: She can shoot some kind of energy from her hand. She did it accidentally against Maryann and possibly less so against a werewolf who attacked her in season 3.]]
** It's revealed that this power, as well as her telepathy, as the result of [[spoiler:her being part-[[TheFairFolk fairy]]. Her blood also allows vampires to temporarily survive in sunlight]].
* Ralph Hinkley from ''Series/TheGreatestAmericanHero'' got new abilities as the plot required, sometimes completely forgetting he could do them by the next episode. This could be a possible subversion in the times that he wasn't sure how he'd done them in the first place, but doesn't explain how, in one episode, he suffers damage to his lungs (while wearing the suit that gives him the powers) from smoke inhalation, meaning his lungs are not protected by the suit. In another (later) episode, he's able to inhale a room full of tear gas without harm.
** In other words, the show justifies ''this'' trope, with the reasonable explanation that the main character doesn't know what his suit can do or how it works. What it doesn't justify is continuity-problematic explanations for ''specific'' powers that the plot demands (such as that lung-protection thing) or the [[ForgottenPhlebotinum forgetting powers issue]].
* Benton Fraser on ''Series/DueSouth'', which is [[LampshadeHanging lampshaded]] in Paul Gross's commentary on the final episode. By the end of the series, he is an excellent marksman, fluent in at least a dozen languages (most of them obscure Canadian aboriginal dialects), a skillful boxer, capable of putting himself into a trance indistinguishable from death, able to listen to concerts in his head by reading the sheet music and ''[[SerialEscalation able to place the location of a plane by listening-in to the radio telemetry.]]''
* Hardison on ''Series/{{Leverage}}'' manages to do this with random skills as they become necessary to the team. As of season 4 he has: painted the office picture (this was [[TheCastShowoff actually done by the character's actor]]), become a lawyer, played a Stradivarius violin, taught himself how to be a forger, topping it off by landing an airplane. This is in addition to his normal roles as a [[PlayfulHacker computer hacker]] and TechnoWizard.
* Thanks to being dosed with Cortexiphan as a kid, Olivia on ''{{Series/Fringe}}'' can read minds, move things with her mind, heal rapidly, shift between universes, possess other people, set things on fire with her mind or control nanites in someone else's bloodstream and never usually displaying the same power twice. Basically whenever a power is needed on the show, Walter just goes "Thanks to the Cortexiphan you were given, it should be possible for you to [insert required power for episode here]."
* In ''Series/BuffyTheVampireSlayer'''s season 3 episode "Lovers Walk", Willow and Xander have been kidnapped by Spike. Oz manages to locate them with his highly refined werewolf sense of smell... while in his human form, which had never been shown to possess any supernatural abilities prior to this. It freaks both him ''and'' Cordelia out.
** In the Seventh Season, a flashback reveals that Buffy sent a telepathic message to Willow and Xander to trick the girls into thinking they were losing so they could fight the BigBad later and defeat him in front of the Potentials to prove a point. Previously, it had been shown that Willow had been able to send telepathic messages, but *she* was the one with magical powers, not Buffy. To further make this an AssPull, it makes no sense in the story because Buffy truly had been getting her butt kicked by the vampire prior to that point, and even her eventual victory over it seems hard-won.
* In the Spanish series ''Series/LosProtegidos'' the villains get new superpowered kids as the plot demands.
* This is done very intentionally in ''Series/{{Carnivale}}'', which revolves around two leads who are introduced with vaguely defined supernatural powers. At the beginning, we're aware that the protagonist Ben Hawkins possesses healing powers, and that the main antagonist [[SinisterMinister Brother Justin Crowe]] has the ability to mentally control people. Then as the series goes on, it gradually becomes clear that neither of them have any real limits on their powers, and that their abilities include (but are not limited to) astral projection, weather control, telekinesis, manipulation of illusions, and the ability to turn water into blood. Not surprising, considering they're from the same bloodline that produced Jesus...
* In the British series ''Series/{{Misfits}}'', they play this in various ways, the most blatant of which is the inclusion of a character whose power is the ability to give/take the powers of others.
** Misfits usually justifies this as what powers a person gets is based on their personality and memories and when the power is given to someone else it can reconfigure itself based on the same criteria. For example: a character suffering from regrets over his own actions gets the power to turn back time, but when this power is given to a holocaust survivor he gets the ability to physically jump back in time to WWII. The power dealer guy might not count as he was introduced to create new plot treads, not to solve old ones. A proper example however is Curtis' DisabilityImmunity that is never mentioned before the episode it becomes useful and is never mentioned again afterwards.
* Sam on ''Series/ICarly'' eventually gained a skillset that included high skill at dancing, singing, painting, fighting, lock picking, speaking different languages and computer hacking, all without ever practicing because she's a lazy slacker.
* In ''Series/{{Supernatural}}'', the Special Children gain new powers, which may be [[JustifiedTrope justified]] as their powers are still developing and increasing, but these powers are often [[ChekhovsSkill quite convenient for the plot]].
** Further justified with the explanation that these powers are dependent on [[spoiler:how much demon blood the person has been drinking.]]
* Sam Beckett from ''Series/QuantumLeap'' develops a "Swiss cheese memory" as a side effect of his time traveling, which coincidentally allows him to [[SuddenlyAlwaysKnewThat remember or instinctively use]] some previously-forgotten ability that just happens be perfect for the situation at hand. Over the course of the series, he has been a pool shark, a piano virtuoso, a talented thespian, a martial arts master, a multi-linguist, and many others.
* ''Series/{{Believe}}'': Bo's PsychicPowers tend to do whatever is needed for the plot like lighting up a tunnel in the "Collapse" episode or creating the illusion of a wall in "Revelation" without any hint that she could do that beforehand.
-->'''Tate''': I didn't know you could do that.\\
'''Bo''': I didn't either.
* The alien entities from ''Series/{{Extant}}'' initially could only give hallucinations and, in some cases, pregnancy. Later the hybrids show up and can use the hallucinations to control humans with increased growth rates and healing abilities thrown into the bargain. What's shown is that they're not very good at combating electronics hence the increased reliance on the in-universe robots "Humanics". Later the hybrids show the ability to come back from the dead, affect electronics, telepathically communicate to each other, the ability to break physical objects with their mind, see the future and transform existing humans into hybrids.
* A number of abilities in ''Series/{{The Flash|2014}}'' seem to be of this kind. Some are used only once and then forgotten. For example, in Season 3, Caitlin uses her Killer Frost powers to make it snow on Christmas (it previously rained). It's not specified how she suddenly became the next Weather Wizard, and she never does anything of the sort again. In Season 4, Barry somehow gains the ability to pull other people into his frame of reference, such as when he has a long conversation with Iris, while a split second passes around them. When Iris asks how he did that, he tells her he doesn't know (previously, someone had to tell him he could do something first, and it usually took a try or two). Barry also somehow can move at superspeed without causing huge winds to throw random paper around him, if he really wants to.

[[folder:Puppet Shows]]
* {{HandWave}}d) in ''Film/TheDarkCrystal''. At the moment when it would be most convenient, one of the two main characters, who are the last of their kind, exposes wings and starts to fly. They have this matter-of-fact conversation:
-->'''Jen:''' Wings? I don't have wings.\\
'''Kira:''' Of course not. You're a boy.

[[folder:Tabletop Games]]
* In general, most role players have characters with predetermined skills and abilities. If the player characters run into a monster/enemy/whatever that is nigh unkillable, sometimes the storytellers may bestow the characters with a new power to help them combat the threat. While instilling new powers on the fly can help create a more exciting story, it can also seem like a cheap ass pull when done too much (making the player characters look like they can't do anything until the plot says otherwise) or done badly. Leveling can also have this effect in some systems.
* This is such a prevalent trope in superhero comics that most superhero [=RPGs=] have some sort of mechanic to represent it. For instance, the RPG ''TabletopGame/MutantsAndMasterminds'' has a Hero Point mechanic that allows you to turn one of your superpowers into another for a single use. While keeping the new power "in theme" with your other abilities is encouraged, it isn't strictly necessary...
** There are also the Variable structures, which let you have a pool of points to devote to various powers and that you can reallocate every round, and actual powers such as [[AdaptiveAbility Nemesis and Adaptation]].
** And few feats are similarly open-ended. "Jack-of-all-Trades" makes every one of your skills that you don't have points in work as though you had points in it.
* Parodied in ''TabletopGame/{{Paranoia}}'' by the aptly-named "Deus Ex Machina Man".
** Also, if games use the optional ''Latent mutant powers'' rule, the GM is encouraged to throw the players who don't know they have powers into situations where that power would help. While they've had the power the whole time, it certainly seems like this trope for the players.
*** Of course, like a [[BlessedWithSuck lot of things in Paranoia]], this often becomes a ''bad thing'' because all the players are trying to hide the fact they are mutants.
* ''TabletopGame/FantasyCraft'', based (loosely) on open source elements of ''Dungeons & Dragons'' rules has a feat titled "I can Swim" which allows the player character to place their new skill points at any point before their next level up, instead of doing it right when they gain a new level. This can lead to the same idea, with characters suddenly remembering that they totally always knew advanced mechanics in the same scene that their vehicle or golem breaks down. This is because ''Fantasy Craft'' is developed from another system called ''TabletopGame/{{Spycraft}}'', which also contained this feat (''Spycraft'', in turn, was loosely based on the ''D20 Modern'' rules, but the difference is that ''Spycraft'' is actually a good system, unlike its source of influence).
* ''TabletopGame/MarvelSuperHeroes'' has rules for "stunts," creative uses on a hero's primary superpower. By spending experience points, your character can essentially gain another superpower at reduced cost, as long as it's thematically related to a primary power.
* The original ''TabletopGame/DCHeroes'' RPG by Mayfair (later republished by Pulsar Games as the generic superhero game ''Blood of Heroes'') actually included this in a number of game mechanics:
** The power "Omni-Power" allowed the user to replicate pretty much any power at the same rank as this power by paying a certain fee (the base cost of a power from character creation).
** The advantage "Omni-Connection" allowed the character to suddenly pull out a contact of either low level ("My buddy from college is a night watchman there!") or high level ("Wow, Tommy boy did good! He's the CEO!") by paying a fee of 'hero points'
** Buying "Omni-Gadgets" allowed the player to create one use, nebulously defined gadgets. Upon pulling it out, he declared what the gadget's power was, used it, and it was 'burned out', simulating the ability to pull out "Bat Shark Repellant" by declaring the gadget was Animal Control, for example.
** Later modifications to the rule set included "Omni-Scholar" (pull a specific area of expertise out of your... utility belt), and other New Powers as the Plot Demands type abilities.
* ''TabletopGame/ChangelingTheLost'' includes the Goblin Vow merit, which basically combines this with DangerousForbiddenTechnique, allowing the person to make impromptu deals with various abstract things to gain new (temporary) powers in exchange for either doing something, or refraining from something. Breaking the deal is [[DisproportionateRetribution ill-advised]].
* ''TabletopGame/PrometheanTheCreated'' recommends this as a way of unlocking new Transmutations, or even shifting Refinements entirely - your character is on a constant journey of self-discovery, and odds are they won't know just what they're capable of until they're put in a crisis situation.
* ''TabletopGame/MageTheAwakening'' forgoes the previous edition's actual time-travel magic (which basically did nothing but annoy the other players by undoing their actions and/or splitting the party and made combat impossibly bookkeeping-based) with this trope. Technically what time-sphere spells do still involves time travel, but what the players see is just the end effect: suddenly, the Mage spent all of his time at university studying quantum physics and practicing at the gun range even though five minutes ago he was a poetry major with no hand-eye coordination. Mind sphere magic can sometimes have a similar effect by pulling previously unknown (mundane) skills out of the group-mind for short periods or stealing them from another character.
* In ''TabletopGame/VampireTheMasquerade'', any Vampire [=NPC=] at the Antediluvian gets a power merely called "Plot Device", which means that can do whatever the Gamer Master needs them to do to advance the plot, as along as they (at least try to) give some explanation rooted in the used Discipline.
* This is one of the tropes that ''Badass'' is built on. Buying new powers just requires a flimsy exposition sequence between action scenes (a journey of self discovery about being a dinosaur the whole time, a training montage of you learning kung fu, whatever). Or if you've got "Little do you know I am actually a ROBOT!", you can buy new powers in the middle of fight scenes just by declaring that you were secretly a robot (or a ninja, or a mad scientist, or a shark, or whatever) the whole time.
* Following the Batman example under 'Comics', ''TabletopGame/{{GURPS}} Supers'' has an advantage for gadgeteer-type superheroes which allows the ill-defined contents of their utility packs to contain just the thing necessary to escape from mortal danger.
* ''TabletopGame/DungeonsAndDragons'' has this in the Chameleon prestige class and the Factotum. The Chameleon, at second level, has a bonus feat he can change daily to whatever he has the requirements for. The Factotum has a pool of Inspiration Points, which he can use for a buttload of stuff, such as arcane spells, sneak attack, ignoring spell resistance, as needed.
** The ultra-cheesy Pun-Pun build uses a customized Manipulate Form to literally grant him any power that it would be beneficial for him to have. This includes anything you can imagine, such as "Pun-Pun cannot be harmed, directly or indirectly. Any act that would harm him automatically fails, at any place and at any given time. Further, Pun-Pun automatically succeeds at anything he attempts."
* ''TabletopGame/{{Pathfinder}}'' has the Brawler, a hybrid class that combines the Fighter and the Monk, whose primary class feature is best described as this. As long as they still have access to their Martial Flexibility uses for the day, the Brawler can gain whatever combat feat they could qualify for on the fly, including otherwise-situational combat feats that are very effective for their current fight.
* ''TabletopGame/BigEyesSmallMouth'': take Unknown Power and hope your GM is feeling lenient.
* [=FATE=] system games such as ''TabletopGame/SpiritOfTheCentury'' or the ''TabletopGame/DresdenFiles'' RPG encourage gadgeteers and magic-users to have "undefined" gadgets and mystical artifacts (in the case of ''Spirit'') or potions (''Dresden Files''), which can be activated later to get a necessary effect at a critical moment. After the story in which they're used, or at certain (GM-decided) intervals within the story, they reset back to undefined.
** Many Fate games also suggest players at the beginning of a campaign leave a lot of their character sheet blank, especially for players entirely new to the game. When the party comes up against a new obstacle (be it a locked door or a gang of hostiles), players are then allowed to declare their character always had a skill or aspect relevant to the situation and fill it in, unless their sheet is already completely filled out.
* In ''TabletopGame/{{Aberrant}}'', doing this has a significant chance of warping the character - physically or mentally - due to the source of their powers.
* In the ''TabletopGame/ProseDescriptiveQualities'' game ''Dead Inside'', magic powers work this way as characters can learn how to do them by seeing them happen, or are taught by important [=NPCs=] (such circumstances which the GameMaster obviously controls). One, the [[ShadowArchetype Shadow]], exists largely to let the GM offer new powers whenever players are in a tight spot (such as teaching you how to fly while you're busy falling off a skyscraper), or just to tempt them with convenience, but the Shadow's gifts [[PowerAtAPrice usually have a cost]].

[[folder:Theme Parks]]
* In ''Ride/ETAdventure'', E.T. is now able to make the flying bicycles go into lightspeed towards his planet as well as later being able to teleport the riders back to Earth, which of course would beg the question as to why he didn't do this in the film...
* Poultra in ''Ride/JimmyNeutronsNicktoonBlast'' has an added corrosive breath ability, which proves a brief obstacle for the two protagonists.
* Imhotep in ''Ride/RevengeOfTheMummy'' now apparently has the ability to plunge people into Egyptian Hell and back, which is what he does with the riders.

* The writers of ''Toys/{{Bionicle}}'' tried to avoid this trope with their main bad guys, the Makuta. Since at one point, a huge variety of differently colored and shaped Kraata slugs could be [[MerchandiseDriven bought]], they had to come up with 42 different powers for each kind. Since Kraata are basically physical forms of the Makuta's essence, the writers decided to give these powers to them
** They played this trope straight with Artakha, Tren Krom also seems to show off unknown powers (and ''body parts'') at times, but in his case it is justified, since he is just this side of a god, and we barely know him. In the case of the Toa Nuva gaining new powers, it is [[HandWave handwaved]] that they're a special kind of Toa, who have not yet learned all of their abilities.
** It seemed that Tahu was going to demonstrate this trope at one poine, as WordOfGod refused to state how many Makuta powers he had absorbed from the Golden Armour. However the story got LeftHanging before we could have found out.
** In the first movie, Kopaka wore a Mask of X-Ray Vision as his standard mask. But Kopaka wasn't in the second movie, and the writers needed someone to see through the floor to advance the plot. So Whenua's Mask of Night Vision got enhanced by them to the point where it functioned both as a flashlight ''and'' an x-ray device. In the third, when the characters were mutated into forms that could not use mask powers, it was Nuju who received the ability to see through rock with the help of his built-in mechanical eyepiece. It never displayed this function before and made Whenua's similarly out-of-the-blue ability redundant in retrospect.

[[folder:Video Games]]
* ''VideoGame/SonicTheHedgehog2006'' : Among [[TemporalParadox many plot issues]] in Sonic 06, Silver managing to instantly learn chaos control during a fight with Shadow despite having no prior knowledge of it tops the list. Sonic pulled off something similar in Sonic Adventure 2, albeit some time after learning of it from Shadow. Also introduced in this game is the ability to create a space time rift via a double chaos control. Said portals seem to function however they need to depending on what the scene requires.
* ''VideoGame/HalfLife2: Episode 1'', the Vortigaunts go from electric powers to stealing the essence of Xen creatures to rescuing Gordon and outwitting the G-Man himself.
* In ''VideoGame/KnightsOfTheOldRepublicIITheSithLords'', the protagonist finds him/herself in dire straits as he/she is put into a cell full of poisonous gas. Just as all hope seems lost, Kreia contacts you telepathically, and quickly teaches you the Jedi art of [[VideoGame/MonkeyIsland Guybrush]]-caliber breath-holding.
* This happens to Seere in ''VideoGame/{{Drakengard}}'' as part of a ludicrous HandWave that was necessary because [[TheWorldIsAlwaysDoomed they were all doomed]], and the ending couldn't be "[[KillEmAll Everyone was eaten]]."
* In ''VideoGame/BatmanArkhamAsylum'', Batman already has his entire arsenal of weapons on the island - he just doesn't bother to activate or get most of them until the plot requires it. For instance, Batman always had the components for the Ultra Batclaw (the upgraded three-shot version of the weapon), but he doesn't bother to upgrade it until he needs to; [[spoiler:when Poison Ivy's vines destroy portions of the Arkham Batcave while he's inside it, it becomes the only way to leave]]. He also has the Cryptographical Sequencer on him from the beginning of the game - but it only works once he gets Warden Sharp's passcodes.
** The sequel, ''VideoGame/BatmanArkhamCity'', lampshades Batman's apparent habit of going into danger unprepared.
---> Alfred: I see you've requested another equipment drop, sir. Have you considered a larger belt?
---> Batman: Tried it. The extra weight slowed me down.
* To keep the four [[Franchise/SpiderMan Spider-Men's]] abilities consistent in ''SpiderManShatteredDimensions'', ComicBook/SpiderMan2099 gets spider-sense, while Spidey Noir gets improved web-shooting abilities; the changes are [[LampshadeHanging lampshaded]] by the characters.
** Spider-Man Noir also ''loses'' the revolver he used in the comics, most likely to avoid MoralGuardians complaining about kids playing as [[SuperheroPackingHeat a hero with a gun]].
* May come up in ''VideoGame/Persona3'' depending on your dialogue choices. [[spoiler: Assuming the protagonist wasn't just hitting buttons randomly (which you can fess up to), or using her women's intuition (which you can ALSO confess to), how DID he/she know which switch controlled the breaks to the train car? In TheMovie, the protagonist had [[IKnowMortalKombat played a train simulator at the arcade a couple of days back.]] Lampshaded in the manga, which revealed the Male MC had a hidden love for trains.]]
* In ''VideoGame/LifeIsStrange'', every new episode, Max gains new abilities that help her when she needs it. In the second episode,[[spoiler: she manages to stop time long enough to get to the rooftop before Kate jumps]], and in the third one, [[spoiler: she learns how to time travel with a picture just so she can prevent the death of Chloe's dad.]]
* Literally in ''VideoGame/{{Psychonauts}}''. Barring three which aren't plot-important, that you get by leveling up, the game basically hands you a new power at the exact time you reach an obstacle that can only be overcome with that particular power. After the first couple of times, they don't even bother giving you some kind of training course to justify it; they just hand you the merit badge and let you get on with it.
* In ''VideoGame/VampireTheMasqueradeBloodlines'', you spend XP directly to improve your abilities, you receive the benefits of doing so instantaneously, and you can save and accumulate unspent XP indefinitely, so any time you run into a task that is too difficult, you can increase the requisite ability by spending XP on it. Run into a computer you can't hack? Spend some XP on your computer skill and try again. Two seconds later, you know enough about computers to successfully hack this one.
* In VideoGame/{{Touhou}} Imperishable Night; apparently, ''everyone'' has the ability to cause an endless night in order to restore the original moon. It makes sense with [[RealityWarper Yukari]], but the rest seemed to incidentally have some sort of magic in order to do it.
* In VideoGame/DmCDevilMayCry, at the end of the hostage exchange sequence, the BigBad Mundas uses his powers to cause a massive chaotic dimensional shift in an attempt to kill the heroes. While Vergil and Kat attempt to escape by car, an earthquake causes them to be thrown into peril. Luckily Dante gains the power to spontaneously shift too-and-fro between dimensions while those in the car suffer from time dilation, allowing him to leap about and rescue them. Tragically he loses this ability the second the scene ends without comment.
* Certain "perks" in the ''Fallout'' games can seem like this, with the PC suddenly becoming able to do something he (or she) couldn't have done just moments ago. However, the fact that these come when the player advances a level instead of at important plot junctures can make it more like "New Powers Slightly After Plot Points Where They Would Have Been Really Really Useful" unless you've played through before or are consulting a guide.
* High-level spells in ''VideoGame/BaldursGateIIThroneOfBhaal'' can seem like this. While spells normally have to be gotten from scrolls and then copied into a mage's spell book, high-level spells are just learned automatically upon leveling up.
* After Mask de Smith from ''VideoGame/{{Killer7}}'' is defeated in a duel with one of the Handsome Men, he suddenly transforms into a Franchise/KamenRider-esque figure with a new super attack and no reloading. Mask transforming and getting stronger is actually a game mechanic, but normally only happens when he finds a new mask, while the transformation with the Handsome Men is completely out of the blue and goes without a word by anyone.
* ''Videogame/WorldOfWarcraft'': While all skills are learned based on character level anyway, there are a few notable examples:
** All classes were homogenized to some degree later on to avoid classes being left out of raids for lack of vital abilities. As such, many were given utility abilities such as spell interrupts, crowd control or debuff removal or had existing abilities altered or expanded.
*** In the early days, Hunters were valuable in raids pretty much for one reason: Tranquilizing Shot, which removed dangerous Enrage effects. Now, a number of classes can do the same, while Tranquilizing Shot now also removes Magic effects.
*** Druids had an unique ressurection spell, Rebirth, which had a hefty cooldown, but could be used in battle. And no regular ressurection spell like every other healer. As of ''Wrath'', they have both, but also share the ability to ressurect players in battle with Death Knights and Warlocks.
*** Buffs were streamlined so that there are only 8 in total to cover and multiple classes could provide either. This led to several buffs being changed into something entirely different, especially the Paladin's Blessing of Might (Mastery instead of Attack Power, a stat that didn't even exist before the revamp).
** Another notable addition is the Mastery passive skill, which provides unique benefits depending on class and specialisation based on Mastery as a stat. All classes learn the skill at level 80, because no items below around that level provide any mastery. Even though the passive provides a basic boost and affects the class in general or abilities it has had for a long time.

[[folder:Web Animation]]
* ''WebAnimation/{{RWBY}}'': As early as the first episode, it's hinted that Ruby's silver eyes are special in some way. At the end of the third season, Ruby activates the secret powers her eyes have, freezing the [[{{Kaiju}} Grimm Dragon]], but not outright killing it, in place and defeating SuperMode![[ArcVillain Cinder]] off-screen. Afterwards, it's explained that "Silver Eyed Warriors" have special powers that allow them to beat even apocalyptic [[TheHeartless Creatures of Grimm]] with ease. The next season then reveals that the Four Maidens, legends hyped up throughout the last season, happen to be weak to Silver Eyed Warriors, sidestepping how Cinder could be defeated and crippled despite having stolen the Fall Maiden's powers. However, she's considered a novice by the people who have dealt with her kind before, and as it turns out, her powers might not work on normal humans, giving her a critical weakness.

[[folder:Web Comics]]
* Aylee from ''Webcomic/SluggyFreelance'' gets this a lot due to periodically undergoing some involuntary ShapeShifting. At various points she's gained the ability to regenerate, fly, breathe fire, extend and retract poison spikes, and emit electro-magnetic pulses. She loses most of her old abilities whenever she assumes a new form, however, so it hasn't made her overpowered.
** Aside from the involuntary nature of her shape-shifting, she's also hampered by the time it takes to adapt. She could enter a cocoon and mutate a new form to counter the current threat, but emerge only months after said threat has been dealt with, leaving her in a body she has no idea how to operate or maintain.
* [[Webcomic/TheNonAdventuresOfWonderella Wonderella]] totally gets like a spillion powers when tied up.
* The Monster in the Darkness from ''Webcomic/TheOrderOfTheStick''. The author has stated that he is a pre-existing monster, but we'll have to wait and see how well his abilities synch up with what he is.
** It's been suggested that he has [[http://www.d20srd.org/srd/spells/wish.htm Wish]] as a spell-like ability. And Wish can do practically ''anything''.
* ''Webcomic/ElGoonishShive'' has a magic system that allows for characters to gain new powers as needed. When [[http://www.egscomics.com/index.php?id=832 someone uses magic,]] their magic gets stronger, and they gain more spells. Characters typically get spells based on [[PersonalityPowers who they are and what they do,]] but were someone to "awaken" as a mage under unusual circumstances, they would [[http://www.egscomics.com/index.php?id=963 gain spells based on those circumstances]] for a while. Considering the author's usual approach to {{Foreshadowing}}, this typically means that, while characters often gain new powers, they tend to do so [[http://www.egscomics.com/index.php?id=1131 a bit before]] [[http://www.egscomics.com/index.php?id=1149 the plot demands them.]]
* ''Webcomic/AxeCop'', having sprung from the imagination of a young child during playtime with his much older brother, tends to have characters randomly gaining powers left and right. Sometimes its explained, and sometimes it's "the secret technique no one knows" or something one of the characters "always had". The adult drawing the strip and crafting it into structure plays such moments for all the laughs they're worth. This truly meets its apex when Axe Cop gains the ability to fly ''by asking his creator to give it to him.''
* In ''Webcomic/{{Sonichu}}'', AuthorAvatar Christian Chandler displays this trope in increasingly absurd ways, up to and including spontaneously bringing his [[DistaffCounterpart twin sister]] to life through the combination of a [[ItMakesSenseInContext a torch made from Pixelblocks and an ancient Cherokee ritual]].
* ''Webcomic/{{Homestuck}}'':
** John Egbert gives a fellow [[PhysicalGod God-Tier]] player advice on using the new powers based on this trope. A player unlocks their powers depending on how important it is ''to'' them to use them, not simply ''for''; if they do not have the conviction, then they simply can't do much even if told that their class/aspect combo has the ability. Given that said player, after a shift in perspective and goals, showed a significant improvement in ability, it seems to hold true.
*** This is a result of the game's artificial limitations on God Tiers, as making them too powerful would take away from the point of the game. They only figure out their potential when they need it the most.
** [[MonsterClown Makaras]] seem to have a nack for getting new abilities. Such as Gamzee being able to manipulate fears and materialize objects based on them, including [[spoiler:Li'l Cal himself]], Kurloz having a form of mind control similar to those of the Serket's, and [[spoiler:Gamzee being extremely difficult to kill on account of being a clown]]. The first two, and possibly other abilities, at least have some kind of linking theme of being related to fears, and are possibly part of their Sgrub-given powers. Their aspect, Rage, has not yet been properly defined after all. But the last one makes no sense and the closest foreshadowing it gets is [[spoiler:the lack of any form of Gamzee having died on-screen and the lack of any ghosts of him in the Dream Bubbles, even though it was implied that (B1) Jack Noir took out his dreamself]].
* ''Webcomic/GrrlPower'':
** PlayedForLaughs in the backstory. Maxima, the most powerful super on the planet, has so many powers that she used to just discover new ones every once in a while. Such as when her roommate popped a bag by her ear as a prank, and she blasted a giant hole in the wall, missing him by less than an inch.
--->'''Maxima:''' So... apparently I can do that.
** Vehemence is constantly pulling new powers out of his ass. Root himself to the ground to keep from being lifted, create new pants after bursting out of his original pair while growing to ten feet tall, awakening all the unconscious heroes and villains and also causing them to fight each other, etc. Handwaved by the explanation that he can use his "vehemic energy" to do pretty much anything he can think of, especially when he has mountains to spare.
** Sydney a.k.a. Halo gains her powers from seven orbs which didn't come with an instruction manual. In addition to having no idea what two of them do, she occasionally discovers that some of them have secondary functions which may or may not be related to the primary. Her telepresence orb also grants her an incredibly powerful truthsight, her shield orb has a button for shrinking and enlarging it, and her flight orb cancels vertigo.
* ''Webcomic/MountainTime'' has Dave, who has shown the ability to duplicate himself (at least enough times to make a basketball team), teleport, shapeshift, fly, create portals to other dimensions out of nothing, pluck out his heart and turn it into macaroni salad, and cause others to shrink and/or grow. [[ArsonMurderAndJaywalking He is also adept at carpentry.]] As these acts are all done at his whim, there's no telling how much he's holding back.

[[folder:Web Original]]
* ''Roleplay/InfiniteJustice'': This is literally Daud Andreas' superpower, which lead to his [[AdaptiveAbility Adaptive Regeneration]] becoming [[PhysicalGod godhood]].
* ''Literature/WhateleyUniverse'''s kids have had their powers less than a year, and they went to [[SuperheroSchool Whateley Academy]] to learn to use them. So most of their powers are ChekhovsGun, ChekhovsSkill, TrainingFromHell, or TookALevelInBadass. Still, some of Tennyo's powers are definitely NewPowersAsThePlotDemands. I mean, the reality warping that ripped open a hole in space-time? Come on!
* This sort of thing was curbed and curbed hard in the ''Roleplay/GlobalGuardiansPBEMUniverse''.
** While the ''TabletopGame/HeroSystem'' [[ExperiencePoint experience point rules]] were being used, there were rather strict guidelines regarding what NewSuperPowers could be purchased, depending on the character's base concept. If a power didn't fit the concept, then the power was simply not allowed. Period.
** Characters who used a SwissArmySuperpower or SwissArmyWeapon were often granted more leeway with this than other characters, but even then the players in question had to justify their taking certain of the odder, more "out there" powers.
** The only character who was really allowed to get away with this was the Blood Red King, but he was a different kettle of fish altogether.
* ''WebVideo/ItalianSpiderman'' has this in spades. He can teleport, outrun motorbikes, make chickens lay eggs (or cigarette packets), control spiders, summon penguins, fly, and his mustache can be detached and used as an exploding projectile.
* Creator/RobertBrockway of ''Website/{{Cracked}}'' points out how pieces of {{phlebotinum}} in a ScienceFiction story gain NewPowersAsThePlotDemands, making technology [[ClarkesThirdLaw hard for the viewer to tell from magic]]. This is one of the [[http://www.cracked.com/blog/4-realizations-that-will-ruin-science-fiction-you/ 4 Realizations That Will Ruin Science Fiction for You]].
* In ''Literature/{{Phaeton}}'' Trayen does this all the time, justified in that his power is controlled by the osmosoul.
* In ''Literature/{{Worm}}'', Eidolon explicitly has this as his power. In any given situation, he can focus on the powers that he needs to combat it and end up with up to three major powers. They take time to build to full strength, but when he's prepared he is effectively worth any three high-level heroes.
* Justified in ''Literature/{{Price}}.'' In setting known as a 'Surge', all supers have the ability to change their powers. At a [[TitleDrop Price]]. Most supers would rather lose than use this power.
* Conveniently in ''WebVideo/VaguelyRecallingJoJo'', Heirophant Green can create gems for communication (Heirophant Call), bandage wounds (Heirophant Mosaic) and splash water (Splash) on things.
* {{Averted}} in ''Roleplay/AHDotComEternals''. The titular immortal humans can regenerate after being killed or wounded, survive in alien atmospheres or even in a vacuum without protection, and cannot die unless their head is separated from their body. They have no powers beyond these three.
* ''Literature/MagicalGirlPolicy'': This trope seems to be the process through which the Spirit Guard gain new abilities.

[[folder:Western Animation]]
* ''WesternAnimation/InspectorGadget''. "Go, go, Gadget !"
** A particularly bizarre instance happened in the episode "Prince of the Gypsies". At one point, a MAD agent challenged Gadget into picking up a scarf while on horseback, and he must do so [[ImpossibleTask using only his teeth]]. What does Gadget do? He deploys his "Go-go-Gadget teeth", which causes a set of ''automated flying dentures'' to pop out of his mouth and grab the scarf with ease. Why Gadget would ever have such an unusual gadget in the first place is anyone's guess.
* El Dorado, one of the [[TokenMinority many token minorities]] of the ''WesternAnimation/{{Superfriends}}'' was the poster child of this trope for a long while.
* ''WesternAnimation/AvatarTheLastAirbender'' has a downplayed version of this, in that the powers frequently appear As The Plot Demands, but are logical extensions of the characters' abilities. Katara learns to heal with Waterbending after being burned, Toph invents Metalbending (supposed to be impossible) because [[DisabilitySuperpower the earthbending she uses to compensate for her blindness lets her feel bendable impurities in her metal prison]], and Aang [[spoiler:is taught to ''Spiritbend'' to take away Phoenix King Ozai's Firebending abilities without killing him.]]
** ''WesternAnimation/TheLegendOfKorra'' plays this straight, when [[spoiler:Bolin]] spontaneously develops a rare talent [[spoiler:(lavabending)]] while under duress. Another character, shocked by the sudden display of power, exclaims "You can [[spoiler:lavabend]]!" and [[spoiler:Bolin]] responds, "I know, I just found out..."
** The series also gives an inversion: usually people don't get hurt by simple thing like a fireblast to the face, but some people do, whenever the plot requires Aang not to learn firebending yet or Zuko to be scarred for life.
* ''WesternAnimation/DannyPhantom''
** A frequent element used where the main hero will often get new powers that'll ultimately help him in the end, the most blatant example being [[ElementalPowers ice powers]]. Season 3 did this with more than just Danny, though -- Danny got ice powers and temporary weather powers, while Kitty got some bizarre kiss-the-men-away power that seemingly came out of nowhere. Johnny better be careful not to upset her now.
** Played for laughs once. The BatmanColdOpen MonsterOfTheWeek fired an energy beam at Danny, and he generated a reflective shield instinctively. Once the beam rebounded, he remarked:
---> Danny: Awesome! ...Now, how did I do that?
* ''WesternAnimation/RickAndMorty'' parodied this once by making the new powers unnecessary before they could be used.
--->'''Rick''': Quick, Morty, you've got to turn into a car.\\
'''Morty''' What?!\\
'''Rick''' A long time ago, I implanted you with a sub-dermal chip that could call upon dormant nanobots in your bloodstream to restructure your anatomy and turn you into a car.\\
'''Morty''': Oh, my God!\\
'''Rick''' Concentrate, Morty. Concentrate and turn into a car, Morty - Never mind. Here's a taxi. Get in. It's fine.
** This power gets activated by accident in the post-credits scene, while Morty is in class.
* ''WesternAnimation/TeenTitans'':
** Comicbook/{{Raven}} can do pretty much whatever she wants depending on the situation. She mainly relies on {{Flight}} and [[MindOverMatter telekinesis]], but has demonstrated the ability to use clairvoyance, [[TimeStandsStill stop time]], [[IntangibleMan pass through walls]], see brief [[{{Seers}} glimpses of the future]], create monsters and [[VoluntaryShapeshifting change her appearance to a monster]] to "persuade" a villain to help them, [[VillainTeleportation among]] [[DemonicPossession other]] nasty [[{{Mindrape}} things]].
** As a villainous example, Brother Blood fits as well (in fact, his powers seem remarkably similar to Raven's, apart from the MindControl). Also overlaps with PowerCreepPowerSeep, as he goes from a psychic with a CompellingVoice (in his first appearance) to a near-god who can take all the Titans at once effortlessly and is only stopped by DeusExMachina (the season finale).
*** Ironically [[spoiler: he would be defeated by Comicbook/{{Cyborg}}'s own new plot-based power, which was to magically leech parts from Blood until Cyborg regenerated all of his mechanical components, conveniently rendering Blood incapacitated. He even lampshades this at the end, where Beastboy remarks now Cyborg is part magical, with Cyborg retorting that it was just a one-time thing. Oh and the power was said to be of love and friendship]].
* ''WesternAnimation/ThunderCats'' loved this. Cheetara's psychic powers, Tygra's illusion abilities, almost anything the Sword of Omens did. And that's just the tip of the iceberg.
* While ''[[WesternAnimation/{{Birdman}} The Galaxy Trio]]'' had consistent enough powers for Gravity Girl (play with gravity, usually by making things fly) and Meteor Man (grow parts of body, super strength follows), Vapor Man seemed able to do just about anything by attaching "-vapor" to the end. This included, but was not limited to: combustible vapor, freezing vapor, storm vapor (read: lightning), explosion vapor, and steam.
* Artha and Beau from ''WesternAnimation/DragonBooster'' display this a ''lot''. It is explained that Beau has many hidden powers that would manifest themselves with training and experience. This, however, does not explain why the majority of these powers only appear for one episode and then vanish for the rest of the series. Especially jarring in the case of Artha and Beau [[spoiler:fusing together at the climax of one episode]], as the theme of combining abilities was ''central to the series.''
* In an episode of ''WesternAnimation/{{Doug}}'', Doug quickly regrets inviting Skeeter in on creating a story about his superhero alter ego Quailman when Skeeter's own avatar the Silver Skeeter starts pulling powers out of his ass left and right.
** His inspiration, the Silver Surfer, is known for doing the exact same thing. PowerCosmic is more or less a ticket to do this.
* When ''WesternAnimation/ThePiratesOfDarkWater'' was a miniseries, Tula was just a talented thief. When it got picked up as a series, she quickly gained heretofore unknown (even to her) powers of "[[{{Whatevermancy}} ecomancy]]", effectively making her Mati from ''WesternAnimation/CaptainPlanetAndThePlaneteers'', but more with plants.
* Speaking of [[WesternAnimation/CaptainPlanetAndThePlaneteers Captain Planet]], there was the titular hero himself, pulling out new powers out of nowhere anytime he needed to clean up the latest mess.
* ''WesternAnimation/Ben10AlienForce'': The Omnitrix's ability to repair genetic damage, first seen in "Max Out".
** For that matter, the Omnitrix [[SuddenlyVoiced talking]], from the same ep.
** The adding of new aliens in the original series almost always worked this way (except for the monster aliens), with their powers just happening to be useful towards the MonsterOfTheWeek. It would sometimes be done in different ways such as someone with greater knowledge of the Omnitrix unlocking a specific function or just random unlocking from playing around with it
** Same for Ben himself. The writers decide to give him photographic memory so that he can remember some runes that the BigBad had activated.
** ''Alien Force'' and ''Ultimate Alien'' could get pretty bad about this, such at some point showing Waybig with ''super speed'', Chromastone with the power of flight, and Diamondhead with what's essentially telekinesis.
** ''WesternAnimation/Ben10Omniverse'' has its moments too: [[BigBad Malware]] was initially established as merely being able to [[PowerCopying absorb technology in order to copy its capacities]]. Over the course of his story arc, he reveals the abilities to destroy and/or consume Ben's alien forms (who are for the major parts ''biological'') take over a whole planet and grow into a OneWingedAngel form that is bigger than Way Big.
*** Then in the ''Galactic Monster'' story arc, Lord Transyl suddenly reveals he has the ability to hypnotize people and tries to use it on Ben. Especially ridiculous in that he technically ''doesn't need'' such an ability, considering his main power is Mass MindControl.
* Justified on ''WesternAnimation/GeneratorRex'' due PowersAsPrograms. Rex starts out limited to six weapons (jetpack, giant metallic hands, cannon, sword, giant metallic boots, and hover-cycle), but after receiving some phlebotinum in the first season finale, he starts gradually discovering new weapons, such as a whip, axes, and a hoverboard.
* Cathy from ''WesternAnimation/MonsterBusterClub'' has so many wacky alien powers, it'd be easier to list the ones she ''doesn't'' have. She has a stretchy Mr. Fantastic body, can levitate and perform telekinesis, can glow in the dark at will, spins her forearm around like a drill... and many, many more, all conveniently described on the spot as something Rhapsodians (like her) can all do.
* On ''WesternAnimation/BatmanTheBraveAndTheBold'', Batman uses [[SpiritWorld astral projection]] in one episode -- an ability he's never even been hinted at having before, or has used since. He learnt it from monks apparently.
* ''WesternAnimation/RobotBoy'' does this. When the title character "super-activates", it's as though his circuitry starts running on phlebotnium instead of electricity.
* Jenny Wakeman of ''WesternAnimation/MyLifeAsATeenageRobot'' seems to have gadgets for nearly every situation, [[TelescopingRobot despite her frame]], though she only uses a few of them in more than one episode.
-->'''[[BigBad Queen Vexxus]]''': A cheese grater?! ''She has a gadget for everything!'' How can I ever beat her if I never know what insane gizmo she has up her sleeves?!
* The writers of ''WesternAnimation/{{Futurama}}'' admitted that they liked doing this when writing for alien species. Kif's abilities to climb walls and shed his skin were some examples of it.
** Bender seems to gain a piece of hardware whenever the plot requires, or if the writers need some sort of joke. [[HammerSpace They all seem to]] [[TelescopingRobot come from his chest]].
** Although not a superhero, in one episode Steven Hawking breaks up an argument by suddenly shooting lasers out of his eyes.
--> '''Hawking:''' I didn't know I could do that.
** Lampshaded in one episode when the Professor's new artificial-nose-and-toxic-waste-making machine is then used by him to translate an alien language containing important information.
-->'''Fry''': Isn't that the machine that makes noses?
-->'''Professor''': It can do other things! Why shouldn't it?
* An episode of ''WesternAnimation/ThePowerpuffGirls'' centers around Blossom discovering that she has ice breath ability, conveniently in time to stop a flaming asteroid from crushing the city. In what might be a deconstruction, she actually notices that her new power is ostracizing her from her sisters and doesn't ''want'' to use it to stop the asteroid. She later uses the ice breath in later episodes, although not really more than her other powers.
** In another episode that focuses on Buttercup's lack of a special power, the girls do a vast array of powers that has never appeared on the show and is never mentioned again. These powers include cloning, teleportation, size change, shape shifting and [[Film/TheMatrix bending over backwards in slow motion.]]
* In ''WesternAnimation/JonnyQuestTheRealAdventures'', Hadji conveniently discovered his "latent" telekinetic abilities in the second season (along with a good many other revamps).
* ''WesternAnimation/TotalDramaIsland'': Harold basically runs on this trope, he's a geeky Napoleon Dynamite {{Expy}} most of the time, but whenever a random (and usually incredibly odd) skill is required for a challenge he suddenly becomes useful again.
** In ''Revenge of the Island'', [[NiceGirl Zoey]] suddenly gains great athletic ability and strength the episode after her LoveInterest gets voted off. She's never showed, or even implied, to be that skilled before. But this is quickly explained as a result of her mind breaking, and quickly becomes a case of WithGreatPowerComesGreatInsanity. But then in the season after, ''All Stars'', she's back to her usual self and ''still'' has all the skills she had during that phase, this time with no consequences and no explanation as to why or how.
** In ''World Tour'' [[StalkerWithACrush Sierra]] has a set of random skills whenever convenient. Some of her skills include: basket weaving, balancing stuff and her head, and apparently being part german.
* ''WesternAnimation/TheVentureBrothers'': "Dude, no one tells me anything!" While 21 doesn't quite develop new powers, it seems that he's informed of the costume's latest capability the second it becomes necessary.
** Phantom Limb's powers also seem to change from season to season. In the first season, he can OneHitKill any animate thing by touching it, and this makes veins grow very prominently on their corpse. He still is able to do this in seasons 2, 3 and 4, but the vein effect is replaced by his invisible limbs glowing brightly as he does his thing. In season 4 and onward, he also seems to be able to detach and independently control his limbs, and by the fifth season he has also picked up the ability to [[ShockAndAwe electrify his arms]].
* Roger from ''WesternAnimation/AmericanDad'' is one of the best examples of this trope you can find, to the point where even ''Roger'' is surprised to find out he has certain powers.
-->'''Roger (after Stan set him on fire):''' How did you know I was fireproof, I didn't even know! ... You did know, right?
* ''{{Transformers}}'' does this on occasion. In the [[TransformersGenerationOne the original series]] Optimus Prime revealed he could mentally control pieces of his body after being disassembled by Megatron. Ironhide sprayed a huge variety of liquids from his sprayer-hand, from glues to liquid nitrogen to firefighting foam to oil to paint, and each liquid would be just what was needed for the situation. ''WesternAnimation/BeastWars'' had Blackarachnia show off telekinesis after becoming a Transmetal 2 (for one quick scene and never again), and there were so many instances of New Weapons As The Plot Demands (in one episode Cheetor pulls a massive missile launcher ''bigger than he is'' out of nowhere, fires it once (missing his target and accidentally hitting Optimus), drops it and forgets about it. The various Japanese ''Transformers'' series are even worse about it.
** Processor-over-matter from ''WesternAnimation/TransformersAnimated,'' which seems to be concentration/meditation as a CharlesAtlasSuperpower that allows for telekinesis, is not seen or mentioned until the season 2 finale, where cyber-ninja Prowl uses an incomplete version of the skill to escape some handcuffs that also paralyze the 'bot they're used on. However, the ability is not immediately forgotten and Prowl spends the rest of the series trying to master it, eventually succeeding.
* Near the end of the first season of ''WesternAnimation/{{WITCH}}'', Will spontaneously uses the ability to have the Heart of Candracar duplicate itself to fool the bad guys. She never uses this again.
** In the second season, all five girls develop secondary powers seemingly out of nowhere--Hay Lin can become invisible (often something related with the element of air), Taranee can read minds, Cornelia gains telekinesis, Irma gets mind control (though this was first demonstrated early in season 1), and Will can talk to electronic appliances. Will also discovers her real element, thanks to Nerissa, and instead of going with 'the Heart' and 'Rebirth', she can use 'Quintessence'. They also, at the very end of the second season, reach their 'zenith' forms, where they each become pure manifestations of their element. The drawback of this is they very nearly lose their minds in doing so.
* ''WesternAnimation/MyLittlePonyFriendshipIsMagic'':
** Pinkie Pie's [[SpiderSense Pinkie Sense]], despite being common knowledge to everyone who had prior knowledge of her in the show, had never been evident before the episode "Feeling Pinkie Keen", and has seen little screentime afterwards. It almost seems like she only had it to provide that episode's Aesop in teaching [[StrawVulcan Twilight Sparkle]] to not adhere so rigidly to logic and to what can be explained.
** Twilight Sparkle herself defies the trope constantly. Spells brought out on the spot, such as the one she uses on the parasprites in "Swarm Of The Century", and the Cutie Mark creating one she tries on Apple Bloom, fail or backfire more often than not. The ones that do work are justified by her having researched and practiced them previously. Also, she constantly seems to have merely forgotten about spells she's used without a hitch that could significantly aid the current issue.
* The AnimatedAdaptation of ''WesternAnimation/{{Beetlejuice}}'' is an unusual variant in that Beetlejuice displays all kinds of weird powers, but since the show is a comedy rather than a "good vs. evil" show, it's typically done through RuleOfFunny more than anything else.
* It's not a "superpower," but similar to Franchise/{{Batman}}, the eponymous heroes in ''WesternAnimation/SWATKats'' often got new gadgets as the plot demanded. The worst of them were arguably the cockpit-cutter from "The Giant Bacteria" (a missile specifically tailored for extracting a pilot from his plane, which was never seen again) and the real offender, the Wire-Clipper Missiles from "Night of the Dark Kat," which seemed perfectly tailored for capturing Hard Drive in his EnergyBeing form.
* ''WesternAnimation/MegasXLR'' abused and lampshaded this trope, including having a button in one episode that was labeled "same button Coop used a minute ago" which, of course, produced a completely different effect.
** That happened to be the [[PlotSensitiveButton Plot-Sensitive Button]] he ALWAYS used at least once an episode.
* Of all things, ''[[InvokedTrope invoked]]'' in ''WesternAnimation/{{Redakai}}'' in reference to [[MagicByAnyOtherName "Inner Kairu"]] which allows one to perform feats straight out of ''VideoGame/TheForceUnleashed''. It is explicitly stated that one's Inner Kairu develops "when the time is right".
* In WesternAnimation/KungFuPandaLegendsOfAwesomeness, Po gets new powers each time some mystical artifact passes by the Jade Palace which he eventually has to use against some bad guy who wants it (even though he's responsible for causing property damage along the way). Of course, most of these powers are never mentioned again.
* Mocked in the "Good Time with Weapons" episode of ''WesternAnimation/SouthPark''. When the boys were all playing as ninjas, Cartman kept on giving himself all sorts of powers, much to friends' annoyance.
--> '''Kyle:''' Okay, hang on guys, I'll use my special power to see into the future, and find out where we should head next.
--> '''Cartman:''' Hold on you guys, I actually have another power. I can see into the future too, but better than Kyle. Let me try.
--> '''Kyle:''' God damn it, Cartman, you can't keep making up powers!
--> '''Stan:''' Yeah, dude, that's like the fifth power you've come up with!
--> '''Cartman:''' I am Bullrog, and I have lots and lots of powers.
* ''WesternAnimation/TheSimpsons'' episode "Raging Abe Simpson and His Grumbling Grandson in 'The Curse of the Flying Hellfish'" has a good and evil version of this trope. For the evil version, in most other episodes, Mr. Burns is [[MadeOfPlasticine humorously old and frail]]; however, in this episode's climax, he [[EleventhHourSuperpower suddenly has the strength to]] [[WouldHurtAChild kick Bart into the safe and send him overboard]]. For the good version, it made way for Grandpa's [[TookALevelInBadass taking a level in]] [[BadassGrandpa badass]].
* Cronus, the BigBad of ''WesternAnimation/ClassOfTheTitans'' seems to pull new powers out of his godly butt almost every episode, which he would never use again, despite how helpful they might be. Yes, he is a Greek God, but still.
* "Let the Nightingale Sing" from ''WesternAnimation/DocMcStuffins'' reveals that Doc's magic stethoscope not only can animate toys, but is also apparently capable of transporting both her and them into the real life version of a scene depicted in a book, something apparently even she wasn't sure it could do until she actually tried it and it worked. She's so excited about meeting the real life Florence Nightingale as a child that she decides to double down and break another show convention by revealing the amulet's magical animating powers to her.
* The title character of ''WesternAnimation/StevenUniverse'' is a half-human, half-alien hybrid that seems to unlock new powers every other episode. This includes [[spoiler: energy shields, healing saliva, the ability to activate magic teleport pads and other artifacts, granting sentient life to watermelons, telepathy, shape shifting, mind swapping with both his sentient watermelons and a human, personal gravity control, magically fusing with a human into a single entity, and instantly knowing how to perfectly drift race a car on first use]]. This is in addition to the physical fortitude and agility of at least a peak human (if not higher) despite his physique and lifestyle not backing that up.
* Justified in ''WesternAnimation/VoltronLegendaryDefender'', as the Paladins are new to the Voltron lions and are learning on the fly what they can do, separately and as Voltron.
** Less justified is Princess Allura. During the second half of Season One, she seemed to reveal a different Altean ability every other episode.
* ''WesternAnimation/WinxClub'' the show starts like this, with Bloom using magic to drive away some shadow beasts, though she never used magic before.
** technically the Enchantix is an in-universe example, given that most of the Enchantixes are gained by the fairies putting themselves in situations where they would die if not for their new powers.