Strong as They Need to Be

"Vegeta: Wait a damn minute, something's wrong here.

Gohan: Huh?

Vegeta: Back on your planet, the Namek couldn't even stand up to Nappa. Yet here he is, now, taking on Freeza. In his second form!

Gohan: What do you think happened?

Vegeta: Well, either Freeza hit me so hard I'm in a delusional coma, or...

Gohan: Or...?

Vegeta: Power Levels ARE BULL$#!%!"

- Dragonball Z Abridged

Every so often, the villain is just too powerful. They're going to destroy the world, or at least control it. Sometimes, if the writers really want it to seem like a big deal, the villain will threaten the entire galaxy, universe, or even multiple realities. It seems all hope is lost. And there's nothing the heroes can do to stop it.

Then, suddenly, the hero will decide that he's serious. This time is for reals. He'll whip out some until now unforeseen strength, and promptly show the villain what for, usually demolishing the bad guy so completely that it prevents them from ever pulling that world threatening crap again, or at least until the writers want them back.

This trope isn't merely The Power of Friendship, nor The Power of Love. It isn't just a Forgotten Superweapon, and only rarely is it related to positively sick levels of training. No, this trope is only really in effect when a character suddenly displays a level of power that has not even been hinted at up until its point of use. There have been no scenes depicting the character practicing towards this level, and no dialogue has given any indication that the character is aware that they are capable of it, or indeed, that they even know this level of power to be possible. They simply find themselves in need, and are subsequently capable of defeating their enemy, with no outside help whatsoever.

If any explanation is given at all, this is usually handwaved as the character having simply held everything back up until this point, never mind all the dangerous, possibly near-death encounters they've most likely been through up until this point that could've really used something like this.

Another possible explanation is that the extra power is used only in dire emergencies because it's extremely dangerous (or, worse, is positively guaranteed to cause Really Bad consequences). If so, it's an example of Godzilla Threshold, not this trope.

This trope does not always need to involve powers relating directly to beating the tar out of things, of course. If any hero is suddenly able to call upon powers they've never shown or hinted at before, with no explanation given by him or any other character, chances are they're Strong As They Need To Be.

It goes the other way too. Characters can often be found struggling to defeat a particular foe, when considering their skill and compared to the baddies they faced in the past, it should be a piece of cake. Used to pad out time length with elongated fight sequences as well as to prevent the protagonists from defeating a villain that the writers need for later. This conspicuous decrease in power invariably is a staple of Shounen filler arcs.

Often a result of the writers letting the Rule of Cool take over. Compare with I Am Not Left-Handed and New Powers As the Plot Demands. Can overlap with Crouching Moron, Hidden Badass, and Power Creep, Power Seep, and Berserk Button. If called upon to Hand Wave or put a lampshade on this, the character might give a World of Cardboard Speech. Contrast Drama-Preserving Handicap. For the phenomenon of "As Big As They Need To Be", see Artists Are Not Architects, Your Size May Vary, and Telescoping Robot.

Anime and Manga

 * Asuka, in the End of Evangelion, manages to kill (sorta) NINE EVANGELIONS. Each with the ability to fly, and each armed with a massive greatsword . With only 20 seconds for each, due to her power cord being cut. Armed only with a short knife. After having just wiped out a small army of a battleship, several tank battalions, a couple of artillery brigades and a few more VTOL gunships..
 * In Dragonball (particullary Dragonball Z), this is very common. One character is beaten, and a few moments later (without any chance of training), he is so much stronger that he can beat the guy who has just defeated him without even sweating. This is Justified by saying that "Saiyans get stronger after losing a fight".
 * Goku, although he mostly relies on Training From Hell, is not above doing this when the chips are down.
 * No, literally. Goku directly invoked this trope in the Buu Saga, using up the rest of his time on Earth to force himself to a ridiculously high Power Level and hold off the villain long enough for Trunks to escape.
 * Bleach's Ichigo. For a large amount of time during the Bount Arc, Ichigo is unable to use his Bankai, for very loose reasons. Then once he is able to, he still isn't as strong as the last time, despite being immune to the spirit damping effects of the real world.
 * Ash Ketchum. One minute he's beating a League champion in a tough battle. The next he's struggling against some also-ran. Though to be fair, a lot can depend on which Pokemon are being used at the time...
 * His Pikachu too, for that matter. At one point, it manages to One Turn Kill a newly rested Regice with Volt Tackle (only the second time in the series that a Legendary Pokémon lost a one-on-one fight with a non-Legendary, and the previous time was a long, drawn-out fight in which the non-Legendary had a Type advantage). A few episodes later, it's having trouble fighting an Elekid.
 * By now he's started intentionally handicapping himself by starting with a totally new team for every league save Pikachu. That doesn't explain why Pikachu's performance is spotty at best. All in all, it's actually gotten weaker as the series goes along, perhaps a reaction to the writers realizing Pikachu winning every battle would be boring. On the other hand, it'd be nice if they justified it in some way at least.
 * Makes sense if the super-charging it got early in the series is slowly wearing off.
 * In Paul's case at least, he actually battled in the Kanto, Johto, and Hoenn Leagues, so he has as much experience as Ash.
 * Ash has more. Ash did the Battle Frontier in Kanto and won (And offered a position as a Frontier Brain). Paul has not been shown to have participated and later actually challenged and lost to Brandon and express surprise when he discovered Ash had previously beaten him.
 * Ash had several advantages in his battle against Brandon Paul did not have. Brandon used four Pokemon against Ash, and he wasn't allowed to substitute, while Ash could. Brandon could use six Pokemon against Paul, and both could substitute. Meanwhile, Brandon used Regice, the legendary he had the least time training with against Ash, with Paul, Brandon used all three. Not to mention Ash won by the skin of his teeth.
 * Not to mention Paul's emotions got the better of him at the time, not like Ash was perfect in his battle against Brandon either. Seismic Toss on a Ghost type? Really? That's an amateur mistake unfitting someone of Ash's experience no matter how you look at it.
 * Soul Eater, such as with the ending of the anime giving the main groups a couple of late superpowers. While the 'courage punch' had some precedent (the important of courage having been used numerous times, but never quite so explicitly), things like had no such setup whatsoever.
 * While was certainly an example,   were nothing new if you read the manga-the alternate ending is to blame, here.
 * This is an explicit power of Kuwabara from Yu Yu Hakusho - his spirit energy literally increases when fighting a stronger foe. It's also evident and completely ignored in most of the rest of the cast.
 * D Gray Man revels in this trope. One time you'll see the whole cast ganging up on a single demon and taking several episodes to beat it, at great cost. The next day, despite being weary of the fight, they can kill them by the dozen.
 * Somewhat averted with level 4 akumas, who are still crazy tough and require you being general strength just to beat one. The first one actually had a lot more punishment than the rest of them as it had all the generals, the protagonist and a recently re-empowered Action Girl against it.
 * In Sailor Moon, Mars and Jupiter seem to have natural abilities that may or may not carry over in their transformed states. Mars uses hers often; Jupiter's implied ridiculous amount of strength, alas, does not really jibe with how fights are choreographed and is much rarer than it should be compared to some other shows. She also tends to get her ass handed to her if she does get to use it.
 * Yoshimori Sumimura works two ways: either everyone's praising him for being way stronger than he should be because he took out a tough opponent; or he's getting lambasted for letting a weak opponent walk all over him. The way he fights tends to be ludicrously inefficient against weaker opponents, though, which provides a legitimate flaw for somebody who's Weak but Skilled to exploit.
 * At least in the manga, Samurai Deeper Kyo was this trope. Period. There are even one or two techniques used by the heroes that they had never tried, just imagined, and after getting a power up or going into a Super Mode, they just do it. And we're not talking about trying a "roundhouse back flying kick". We talk about "the technique that draws my blood make-up over your body to boil your blood from inside".
 * One Piece: This tends to be played for laughs; Luffy defeats Arlong in the previous arc, whose was the most powerful pirate in the East Blue. Yet he's easily restrained by Buggy and his mooks for his "execution" despite showing displays of super-strength and persistence.
 * A rare villainous version: In Tengen Toppa Gurren Lagann, the  is shown to only use as much power as the Dai Gurren Brigade uses. This is to specifically invoke Hope Spot after Hope Spot -- every time the heroes get stronger, the   effortlessly powers up to match them, all in the name of maximizing the terror and despair they feel.
 * The Deconstruction is also mentioned: The end result of being "As strong as you need to be" in a universe where everyone else can do the same thing is the "Spiral Nemesis" -- eventually, two factions each following this trope will fight each other, leading inevitably to the explosion filled destruction of the universe.
 * Fiamma of the Right from To Aru Majutsu no Index explicitly has this as his power. His ability, The Holy Right, usually manifests itself as a giant bird-like claw growing out of his shoulder. The Holy Right is nearly omnipotent, but it only uses the right amount of force to accomplish what Fiamma wants at the moment. The more powerful his opponent, the more powerful it becomes.
 * Inazuma Eleven the Orge take this trope which has already been used regularly up to eleven. First season Raimon has to fight the third season's Bonus Boss, who can easily defeat Zeus, the first season's Big Bad that the heroes needed to struggle so much to win in the TV anime. What do they need to win within 30 minutes? A Kid From the Future, four new players, and some four-tier above abilities the heroes learn because they're getting really serious.

Comic Books

 * Superman loves to do this, to the point that he has occasionally become so powerful that, in order to allow him to believably fight small-time thugs, the writers actually needed to reset the universe. Twice.
 * That would mean Superman's enemies as fall under this, so he doesn't one hit KO them, or vice versa.
 * Early seasons of Justice League left Supes vulnerable to strength fluctuations to give the rest of his teammates a chance and front row seat to The Worf Effect. One instance during the first movie had him taken down by a foot soldier with just one laser blast; the writers admit that they purposely did this as to prevent his teammates from becoming obsolete. Lampshaded in one episode where Flash offers to answer Big Barda's request for help from the League, only to initially be told anyone who wasn't Superman was useless to her.
 * In the Justice League Unlimited series finale, this is explained by saying that Superman always holds back when using his powers, because he "live[s] in a world made of cardboard" and is always afraid that, if he loses control, someone might get killed. "But you can take it, can't you, big man?" He then proceeds to slam Darkseid through a half-dozen (deserted) skyscrapers with a single punch.
 * And then Darkseid got up, pressed a button on his wrist, and Superman went from "I'm not holding back and could kill you" to writhing on the floor helpless.
 * Does that mean we should ignore the fact that in the Superman cartoon Darkseid was undeniably stronger than Superman? Look at their fight in Legacy; all Superman's punches did to Darkseid was make him angry that Superman would hit him.
 * But that could be because Superman was still weak after being exposed to red sunlight for several days.
 * Don't forget, however, that Superman did, in Superman the Animated Series, beat Darkseid to a bloody mess (by DCAU standards) when he and Batman invaded Apokalips. The difference is, at that point, Superman was still holding back so as not to kill him. By the time of the Unlimited finale, he was pretty much actually trying to kill him, since he knew that he probably couldn't. Remember, Supes, unlike Batman, will relax his Thou Shalt Not Kill rule when there absolutely is no other option.
 * Even with the post-Crisis Superman, some writers (Mark Waid is a good example) like to write him as a being of godlike power, capable of surviving things like in Kingdom Come that would kill literally anyone else. Eric Burns describes this as Superman having his "no one can kick my ass because I'm Superman" bit set that day.
 * In the defense of Kingdom Come, there ARE hints earlier in the book that this Superman is much more powerful than others. Luthor himself mentions that Supes is so soaked up on sunlight, he's now immune to Kryptonite.
 * Also, what was stated was that the bomb would have killed Superman if it had hit him point blank. Captain Marvel was presented as exactly as powerful after all, and . (Doctor Fate & Green Lantern, who protected about half of the fighters)
 * And on Smallville, his powers actually do fluctuate, based on solar coronal activity, the fact that they're still developing, and the fact that he lives in a freakin' town full of Kryptonite.
 * Some stories suggest that, like Hulk, Supes' power level is affected by his mood. In For the Man Who Has Everything, he was so mad at Mongul that he actually wanted to kill him, and he went absolutely apeshit on him. Mongul is normally stronger that Supes.
 * One of Superman's mainstay abilities is his Eye Beam, traditionally his only true ranged-attack. Rarely limited by an official explanation (save it perhaps decharges him more quickly if he's acting as a solar-powered battery), Supes generally only uses it against opponents when he's completely restrained or when it wouldn't result in the censors bearing down on him for using it.
 * His invulnerability fluctuates this way too. In some comics, you can put him in a room with a little red sun lamp and kick his ass. In others, he can fly through a red star, then smack into a planet and get up and fight (albeit depowered) as happened in the definitely canon Infinite Crisis.
 * Thor frequently invokes this trope, with the idea that he was "holding back" for fear that unleashing his true power would kill his opponent. Almost always accompanied by a line such as "Now you must face the full might of Thor!"
 * Thor has said that even against superhuman foes on Earth, he doesn't dare use his full strength for fear of killing them. There's clearly some ego involved in this, of course, since Earth has some superhumans who are every bit as strong and durable as Thor, if not moreso (see: Hulk, Juggernaut, Hercules, Sentry, etc).
 * For another DC example, what powers the Martian Manhunter has, and to what degree, varies enormously with who's writing him and the needs of the current story. He seems to have all and only the abilities he needs to put the story where the writer wants it. Sometimes he's like a combination of Superman and Plastic Man (except weaker), and other times he is the most powerful being on Earth (as in a storyline where he turned evil and everyone was terrified of fighting him).
 * For that matter, his Kryptonite Factor toward fire is alternately treated as a Weaksauce Weakness that keeps him from being too overpowered, or a psychosomatic weakness that can be overcome with willpower; the two inconsistencies go hand in hand.
 * In Blackest Night, a zombie MM points out "I'm as powerful as Superman. Why does everyone FORGET that?" before kicking some ass.
 * The Infinite Crisis OMACs are an interesting case. They're villains, which is unusual for this trope, and Strong As They Need To Be is their explicitly stated ability. When they sight a superhero, they'll identify the hero and reconfigure to have the powers and abilities they need to win the fight. Nearly everyone has asked the obvious question, which is: Why are the bad guys going out of their way to give the heroes a fair chance? Why don't they just configure themselves with the Superman-killing abilities and lay waste to everyone? No answer has yet been given. Fan theories quite naturally abound; for example, as machine-based creatues, it's been suggested that it would take far more energy for them to hit someone as hard as Superman could all the time than to reconfigure into more limited forms.
 * The fact that the Infinite Crisis Brother Eye was made by Batman would explain a lot.
 * The Hulk's level of physical might and durability varies tremendously. This one, however, has a built-in explanation: Hulk's physical might--and in the 2003 movie, his physical mass and size--is directly related to how angry he gets. Hence the Catch Phrase "The madder Hulk gets, the stronger Hulk gets." For example, Wolverine has fought him several times--most of the time to a standstill until he manages to get one good cut in and piss the Hulk off enough that his anger really flares up. At the same time, during the Onslaught event, in the last battle with the titular villain, Jean Grey mentally removed any blocks Banner may have had to restrain himself, and he beat the hell out of the physical form of a being that could alter reality with a thought. In short: hope your first punch knocks him out.
 * Similarly to Darwin below, in one story Hulk developed the ability to breathe in space by getting angry enough.
 * Darwin, the Evolving Boy from the X-Men comics literally has this trope as his superpower. Whenever placed in a situation he is unsuited for, he will gain a new power capable of dealing with it. Place him in total darkness and he gets the power to see in the dark. Stick him in a burning building and he becomes immune to fire. Trap him underwater and he grows gills.
 * However, he only gains a power that will let him survive, which doesn't necessarily mean winning. Stick him in a fight with The Hulk, for example, and he gains the ability to teleport into the next state or Nigh Invulnerability that would let him weather The Hulk's fury (but nothing that would let him actually fight back).
 * The Amazons from Amazons Attack!, when Wonder Woman's people invaded the United States seemed to fluctuate wildly in their power. In one scene they're giving Supergirl and Wonder Girl a hard time, then Superman shows up and trounces them effortlessly, then they're taking down fighter jets with flying horses and spears, Batman can beat them in a straight up fight, they can invade Washington DC and the army can't do a thing to stop them, then they get shot down by soldiers. They're not Immune to Bullets, and they beat the US army with spears and giant bees!?
 * Stygian Killer Hornets, thank you... Bees. My God.
 * Spider Man has this problem very often. His strength, while theoretically possible to mathematically calculate, is subject to plenty of fluctuation. Even his webbing is subject to this, sometimes being broken by a Badass Normal and sometimes strong enough to hold up a car or two.
 * The ultimate expression of this was when he was attacked by Firelord. Panicking, dodging, and running for his life, he sees the Herald of Galactus survive everything he can throw at him unharmed, up to and including an exploding gas station. But when two kids nearly get killed by his uncaring foe, Spidey loses his cool - and proceeds to pound Firelord into the pavement, punctuating every barrage of fists with statements on the order of "Hey, you don't attack kids!" It takes the arrival of Captain America and the Avengers to snap him out, by which time Firelord is flat on his back, eyes crossed, and dazed for quite a while. Just to elaborate, this is a being on a power level roughly equal to Thor or the Silver Surfer, and leagues above the power level of Spidey or any of his usual foes.
 * Subverted when Spider-Girl happened to be in similar situation, with evil god Set trapping every superhero on Earth under unbreakable forcefield. May was doing everything she could to beat him and even dropping a building on him didn't slow him down. However, when May called all her Heroic Resolve for one final attack and it was looking like this trope was going to be used....she kicked him in the nuts. After that, Set admitted that he was holding back on her. Unluckily for him, that kick was painful enough to make him stop upholding the force field and released the superheroes who unleashed a giant ass-kicking upon him.
 * The Thing is another character whose strength has actual limits and there are some foes that he simply cannot overpower. Although we pretty much have to be told this for this to be true, at one point he was even asked point blank how strong he was and his answer was "STRONG ENOUGH!"
 * Peter David pretty much stated this trope when responding to comments of his writing of She-Hulk. Fanboys were quibbling about She-Hulk's power level under PAD's run and he said she'd be as strong as the story required - as the story was more important than the stats.
 * Legion of Super-Heroes has the character Nemesis Kid, whose power is exactly this. He develops abilities strong enough to deal with anyone he's directly fighting. If he fights a martial artist, his skills will be superior, if he fights a cosmic powerhouse, his strength will go through the roof. Naturally the only way to defeat him is to go after him in pairs because he can only adapt to one power at a time.
 * Sentry has this problem, one time being able to fight with Hulk as equal, having his ass handed to him by She Hulk or Hercules another and then going into a level where he can  or kill  . May be justified as his powers may depend on his emotional level or
 * Gladiator from the Shi-Ar Imperial Guard and his evil female version Stronian have powers depending on their confidence, so if they fell even smaller fear, doubt or regret, they're getting weaker.
 * This is actually part of Venom (Mac Gargan)'s powers; when injured or threatened, the symbiote can increase in mass and strength to meet whatever threat it is fighting with equal force.
 * Deadpool, whose healing powers are literally taken from Wolverine, has his own healing ability fluctuate wildly depending on how powerful they need to be for the plot. This is explained away as a result of the constant battle between his cancer and his healing powers, as sometimes the cancer gains ground and sometimes the healthy cells gain ground. It even becomes a major plot point when his healing factor stays in a weakened state and he seeks medical attention to try and improve it. He is literally immortal though, since after meeting Death herself when he was having near death experiences he fell in love with her, Thanos became jealous of Deadpool and prevents his soul from passing on so they can never be together.
 * Jack Kirby's Celestials, through it's more visible at alternate realities - in Earth X they as a whole cannot match Galactus, in other worlds they are capable of effortlessly killing three wielders of The Infinity Gauntlet and in one What If story they can take Dr. Doom, possessing the Infinity Gauntlet AND the power of Beyonder, despite that both are powerful enough to defeat Abstracts, who are supposed to be far above Celestials. And in another reality one of them is no stronger than a fleet of spaceships.
 * Deconstructed with Plutonian in Irredeemable -.

Film

 * Wolverine pulls this off in X-Men: The Last Stand when he faces down Phoenix in the climactic scene of the movie. His healing powers are inexplicably multiplied to the point where he can walk up to Phoenix (who by this point had already atomized several main characters and the entirety of Alcatraz island), taking multiple psychic blasts which flay the muscles from his bones only to fully regenerate in less than a second. This was so egregious that it got a Word of God Retcon, stating that Phoenix's out-of-control abilities also amplified the powers of nearby mutants.
 * In Push, Nick starts out unable even to fix a roll of the dice, and ends up All this with no training, and with very little practice, apparently only because It Was Time For Him To Win.
 * Also, How did he do this? No one, before or after that moment, was ever shown as able to.
 * Godzilla's power varies from film to film. Sometimes, he's able to defeat enemies with a single breath of his atomic breath, while others, he struggles in a tooth-N-claw battle against his enemies.
 * Godzilla almost always suffers a total Curb Stomp Battle, and then inexplicably bounces back more powerful than before. During his "second wind" he will be immune to attacks that caused him severe injury the first time. No explanation is ever given for this.

Literature

 * This happens on both sides of the fence in the Warhammer 40000 fiction. Often Chaos Space Marines or other alien enemies of the Imperium require a lot of Imperial Guard cannon fodder to be hurled at them before they die. Then you have series like Dan Abnett's Gaunt's Ghosts, where the killing of Chaos Space Marines is almost-but-not-quite offhanded.
 * This is often true of the loyalists as well.
 * Guants group did shoot them in the back from ambush while they were utterly massacring another Imperial unit.
 * Orcs get this treatment a lot too. Sometimes they are almost a joke and a minor threat to guardsmen unless they have a huge numbers advantage, and sometimes the same kind will be a difficult fight to Space Marines one-on-one. Same applies to Tyranids.
 * Orcs are a special case. A feral Ork army is almost laughable in terms of strength, while a carefully constructed WAAAGH! is almost unstoppable. Often, you'll see something in between the two. The strength of the Orks depends on the strength of the local WAAAGH! It's a species that runs on Clap Your Hands If You Believe, thus Strong As They Need to Be is easily justified. The writer just has to limit how hard they can "clap."
 * This is not strictly correct. The strength of Orks actually depends on the strength of their opponent. Orks are a survivor race, and much like the Darwin Boy example in the Comics section, Orks are actually a very straight example of this trope. Orks who face a more powerful and able opponent will be just as tough, whereas if the opponent is incompetent they wont be any worse, but they'll not be any better than they would normally be. So it isn't about the whole Clap Your Hands If You Believe, which is not just innaccurate, but overused concerning Orks, but it is that Orks get better through reacting to stimuli. Comparing Orks between stories, or in certain games such as Gorkamorka, where they don't have as much of a dedicated opponent, the contrast is rather striking.
 * Possibly justifiable in cases where the story is about different chapters/regiments/hives/etc. as experience plays a big part in war.
 * This is an explicit rule in Diane Duane's Young Wizards series. The Powers That Be ensure that every wizard has enough power to deal with whatever the current crisis is. Luckily, drama is preserved by making failure a real option; just because you're strong enough to solve the problem doesn't mean you'll figure out the solution, or want to pay the price.
 * This is also why older wizards tend to be weaker than their younger counterparts. Their skill with magic is such that they don't need as much power.
 * Not technically super-heroes, but in "All The Weyrs Of Pern", the dragons and their riders were fooled into picking up and transporting spaceship fuel tanks that were far larger and heavier than the dragons should have been capable of dealing with, because (as Aivas says explicitly) "they can handle anything they believe they can handle".
 * In the Star Wars Expanded Universe, Luke gets new Force powers as needed. So does Jacen.
 * Done well, and justified, in a fight scene from Too Many Magicians: Lord Ashley is dueling a villain whose sword is enchanted, and keeps flickering in and out of visibility. As he's pressed hard by his foe's invisible attacks, Ashley's fear activates his own power of prescience, allowing him to intuit exactly where the blade will strike next. This turns the tables on the villain, who begins a fighting retreat ... at which point, Lord Ashley's growing confidence causes his prescient power to shut down again, as it's established that it only works when he's under stress. Luckily for him, his opponent doesn't realize that's what happened, and when Ashley hesitates, his foe seizes the opportunity to escape rather than attack.

Live Action TV

 * Pro wrestling loves this trope. The good guy will consistently get beaten and be depicted as brutalized and exhausted, until they suddenly bounce back for a victory.
 * Inverted in the MST-bait Puma Man, in which the "superhero" is capable to tearing apart a car or ripping into a brick wall with his bare hands, but at the movie's climax is just barely able to overpower an elderly Donald Pleasence in a struggle.
 * In the Buffy Verse as a whole the strength of vampires varies greatly, from clearly superhuman on a level that can't hope to be matched (Buffy and Angel Season 1) to being able to be beat by the Badass Normal of Angel, Charles Gunn, easily.
 * When asked about the strength of Buffy the Vampire Slayer, Joss Whedon replied, literally "as strong as the plot needs her to be".
 * Semi-averted as well, as she does get consistently more powerful during the course of the series. Comparing her battles in the first season to her battles in the eighth is like night and day. This is particularly noticeable after the Initiative Arc.
 * Angel tended to do this a lot as well. Particularly notable with Connor, whose abilities seemed to correspond directly to how inconvenient it would be. When he's on their side, gets beaten up by practically everything not an ordinary vampire. When fighting against them, took out almost the entire team single handed, twice.
 * In Smallville's Grand Finale, Clark flies up to Apokolips, a planet with engines on it, and shoves it all the way back into space saving the day and exhibiting about a billion times the super strength he's ever demonstrated in the TV series. This is Silver Age level power for Superman and even that character was normally moving inert planets when he moved something that massive.
 * In Supernatural, Hunter Gordon Walker was strong enough to rip off two vampire's heads and could even, but when fighting Sam, his strength appeared to be downgraded.


 * In Toku series such as Kamen Rider, Super Sentai, Power Rangers and the like, this trope is in effect, with power levels depending on how pissed you are, what time of episode it is and how fast the plot needs to move past one fight, and how loud you yelled before rushing in. Hikonin Sentai Akibaranger, a parody Super Sentai series, had the Rangers realize that the general leaving is like an Event Flag for the good guys to start winning; the Monster of the Week was been invincible before, but they realize what always happens soon after the general says something to the effect of "I'll leave this to you" to the monster. As suddenly they're pummeling the previously-unbeatable foe, Red triumphantly cries out that consistent power levels do not exist! Yeah, it's that kinda series.

Video Games

 * In Metal Gear Solid 4, Snake's barely able to fight after being stabbed in the shoulder, but spends a good five minutes in a microwave corridor intended to vapourise anyone who entered immediately after suffering a heart attack, and is still just about able to kick away Scarabs.
 * In Devil May Cry 4, Nero's Devil Bringer normally can only pull Nero to a big opponent and not the other way around. However, under certain circumstances it can abruptly become much more powerful, such as being able to punch the massive fire demon Berial a long way.
 * God of War: Kratos has this all the time. It's particularly notable in the second game when the Colossus of Rhodes stamps on him, and he tosses it away. But there's a wall in the way? Must go all the way around this convoluted route rather than just, I don't know, knock a hole in it. Or in the first game, when your method of getting through a gate with thin bars that something else already ripped a hole in is to push over a 60 foot high statue.
 * Maybe Kratos has extra powers when attacking statues?
 * In God of War 2, his insane strength might be justified that in the beginning Kratos still has all the powers a full-fledged god can brag about, he doesn't brag "Fear the new god of war" while beating the first mooks for nothing, still the trope applies for the rest of the second game and the sequel as well, in God of War 3 Kratos stripped of all his powers he gained on the previous game, can take the pressure of Chronos -- a being who dwarfs the Colossus of Rhodes -- trying to squash him and push him away, after this display of strength it makes one wonder why Kratos needs to face through all the puzzles and locked doors at all.
 * Well, he's a god of war. Maybe he's strongest when he's got something to fight?
 * Ser Cauthrien in Dragon Age Origins is a boss example. Despite being an experienced soldier and undeniably a Badass Normal, she somehow has almost as much health as a fifty foot tall dragon.

Web Original

 * The superheroine Tennyo in the Whateley Universe. In the novel "Boston Brawl", she suddenly gained increased regeneration and strength. In her novel "Christmas Crisis" she went all out to save her parents, and pretty much ripped reality apart. And maybe survived a tactical nuke, or else she somehow teleported away. The author hasn't told us yet.
 * Chou Lee can be 'filled with the Tao', and according to her author, become strong enough to kill anything.

Web Comics

 * Every single character from Bob and George (though it is sometimes justified). For example, at one point George can't even harm the villain with any of his lightning attacks. Yet later on he destroys an entire castle/base by accident. Megaman's intelligence (and thus, battle skills) also fluctuate alot, but this is explained within the story.
 * Actually, it was explained why George couldn't use his powers against Mynd; Mynd was able to just absorb the electricity. There's also the fact he appears to have a limit on how often he can use his powers (his MP- er, Weapon Energy). And by accident? He destroyed that castle because he was pissed that he had been hung up from the ceiling for months and could have done something about it, but he couldn't because he forgot he could.
 * Played for Laughs in Order of the Stick with Crystal. As Haley's personal rival, she is always the same level as Haley. Even if she does nothing to earn these levels.
 * Nodwick's muscle strength is just enough to carry whatever load he is asked to move but is not suggested to have super strength.
 * In L's Empire, the king or queen of the Kayoss will always be stronger than the combined power of those they are fighting.
 * In Homestuck, during the Trolls' battle against the Black King of their session, Gamzee suddenly unleashes never before seen power against him, doing almost as much damage as Vriska, a God Tier character with manipulation of luck.
 * Butch of Chopping Block is overweight and out-of-shape, and was once outrun by an old lady with a walker, but whenever his life is in danger, he becomes absurdly lethal. Chalk it up to the strip's Negative Continuity.

Western Animation

 * In the Green Lantern Animated series, Saint Walker successfully holds his own against a Red Lantern with his bare fists. A guy with a spear bests Kilowog in battle. And Mogo blasts an asteroid that Hal and Kilowog could only slow down, just in time to resolve the episode.
 * In Teen Titans, due to the emphasis on the Rule of Cool, the team's powers and abilities were considerably up and down. One infamous example was the case where superpowerless Boy Wonder was able to singlehandedly beat down Cinderblock, with his bare hands. Every other time however, Robin and his teammates struggled to defeat him. The Titans often reached literal godlike levels during the season finales.
 * Let's not forget Cyborg's little trick of reassembling himself after Brother Blood literally took him apart in a fight. This was so ridiculous that the writers included a line of dialogue stating that this was a one time thing.
 * Raven's strength fluctuations are legendary. In some cases she's been beaten by just having her mouth forced shut, but when the plot calls for it she's capable of soloing her Physical God father. Justified because Raven's powers are fueled by her emotions; the more passionate she becomes about defeating an enemy, the stronger her powers become in order to accomplish it.
 * Starfire is pretty bad about this trope. She can survive extreme environments when the plot calls for it, and be totally helpless when it doesn't. In one episode, Starfire winds up wandering around frozen tundra, apparently in danger of freezing to death. Yeah, this troper realizes that the normal mistaken response is to say "well if she can survive in space..." However, given her super speed, super strength, and flight abilities, there was nothing in that episode stopping her from flying out of the area, or back to Titans Tower to get proper equipment if things get too hairy. Then too there might be an explanation for both her (and Raven's) powers in that they're emotion based, which means that theoretically, a villain could defeat Starfire by getting her depressed enough.
 * Cyborg and Starfire's Super Strength also varies greatly just compared to each other, as one can be shown at any given moment to be several magnitudes stronger than the other.
 * In He Man and The Masters of The Universe, certain of the more powerful villains were shown to be able to give He-Man a good trouncing on their very first try. However, if the same villains found themselves tangling with his weaker archfoe Skeletor, they were shown to be unable to inflict so much as a wrinkle on his clothes. This went on up until the introduction of King Hsss, who proved to be eviler than any of them.
 * In the 2002 version, He-Man's Strong As He Needs To Be nature was perhaps best exemplified by the time he effortlessly lifted a stone tower that had to weigh in excess of a hundred tons and threw it into the sun. Punching any of the bad guys with a similar level of force should've turned them into a pasty smear on the nearest wall, yet they were always treated as legitimate threats.
 * In the comic book version He-Man's special power is specifically defined as the ability to have exactly the amount of strength he needs to accomplish what he's trying to do at the moment, but no more.
 * The Powerpuff Girls are notorious for this. One episode will have them swatting skyscraper-sized monsters with ease (often with just one of the girls doing the dirty work) proving themselves to adult heroes as the mightiest supers in their entire universe, and another will have all three girls get beaten down by a gang of ordinary thugs.
 * Not to mention one time where an overweight nerd was able to trap them in toy packaging. I mean, SERIOUSLY?!
 * Ladies & gentlemen, The Tick. This trope is a perfect description of his "drama power."
 * The in-story description of it is "nigh-invulnerability." The Tick is always the exact right amount of invulnerable to keep the plot going. So he's much more vulnerable during slapstick scenes.
 * The Simpsons: Comedic example: Mr. Burns. He's always depicted as frail and weak, but just how frail and how weak depends on whatever makes the joke work.
 * Also, of course, how late the season is.
 * Mesmero from X Men Evolution. In his first appearance, he's a strong enough telepath to fight Xavier to a draw, but in his next episode Xavier defeats him easily. For most of his appearances he's a Squishy Wizard, but in the Dark Horizon Season Finale he can suddenly take on Wolverine and Sabertooth at the same time. Possibly justified because Mesmero's powers were granted by Apocalypse, and the old mutant may well have adjusted how much power he let his minion use based on how much he thought he'd need.
 * As noted above, Gladiator powers are based on his confidence and his appearances during Phoenix Saga in X-Men really shows it. At his first appearance he simply ignores Juggernaut punching him and then threw him to the ocean with one hand. Later, feeling conflicted about fighting Rogue against his personal code allows her to knock him out with one punch.

Real Life

 * Adrenaline does this. People lift cars up to get someone they care about out from under them.