Weaksauce Weakness



"Raj: I like Green Lantern, I'm just saying it's pretty lame that he can be defeated by the color yellow.

Sheldon: Only the modern Green Lantern is vulnerable to yellow.

Leonard: Golden Age Green Lantern was vulnerable to wood.

Raj: Great. So I can take them both out with a number 2 pencil?"

- The Big Bang Theory

Being a Superhero ain't easy. Most of the original Flying Bricks have the good Achilles heels covered, and the pharmacy is even out of Psycho Serum to give you a cheap Backstory gimmick to explain your powers.

What's left for the modern hero and villain to do? Make do with a Weaksauce Weakness. It's great for comedic effect, but just as often it ends up being an Achilles Heel that makes your average Mundane Solution seem perfectly reasonable by comparison.

The weakness isn't a common household cleaning agent like Mundane Solution, but something so incredibly, stupidly embarrassing you'd think the Superhero would never use his power out of shame in the off chance someone found out about it, or because it shows up regularly in the course of their super heroing. The "weakness" might come in the form of the fuel for the super power, a humiliating Transformation Sequence or activation phrase, or just a set of restrictions on the powers that really are begging to get laughed at. Therefore, this is one of the most popular ways to Bless your hero With Suck.

If the weakness is a Logical Weakness, it can be pulled off. If not, it can seriously stress the Willing Suspension of Disbelief, unless it's Played for Laughs.

Especially cruel writers will have clever villains make it a Weaponized Weakness. However, a Kryptonite-Proof Suit can even the odds.

Related to Why Did It Have to Be Snakes?. See also Weakened By the Light, Kryptonite Factor and Easily-Thwarted Alien Invasion (where Bizarre Alien Biology is probably to blame). If played for laughs, the one so harmed may Fight Off the Kryptonite. In extreme cases, the character will defend themselves from the weakness with a Cross Melting Aura. For the inversion, of being at risk from a lack of something see: Phlebotinum Muncher.

Fiction in General

 * Vampires, the badass creatures of the night who always want to suck your blood, tend to have a lot of weaknesses. Popular tradition holds that you're fine as long as you stay in the sunlight, have some garlic, stay inside your house and refuse to let them in, or even wield a simple cross.

The multitude of fiction involving vampires, though, has led to a multitude of differing weaknesses--including varying degrees of effectiveness. In some settings, vampires are weak to silver, and other religious symbols affect them as much as Christian ones. Then there's the older, more obscure, and even more restrictive weaknesses such as inability to cross running water, or obsessive-compulsive disorder causing the need to count piles of beans or other small objects, inability to stand constant bell ringing, and even the need to be invited to enter houses.

On the inverse, many of the works that tend toward "non-standard" portrayals of vampires also go at length to mock the traditional weaknesses.


 * The Fair Folk are terrific--as in terror-inducing--beings of legend and myth ... and yet, they can be beaten by a stick of iron, a horseshoe, a length of rowan wood, clothes worn inside-out, or a stick of bread.

A popular explanation for the weakness comes from Victorian Era archaeologists, who held that this is all just symbolism for the bronze and stone-working cultures being conquered by iron-working ones. More recent academics (like Dr. Diane Purkiss) have shown there's no archaeological or historical evidence for this.
 * This is an especially big problem for the Nuckelavee of Orcadian folklore. Widely considered the most malevolent elf in all of Scotland, the Nuckelavee is an eldritch horror that resembles a man on horseback, if the man was fused to the horse and both had all their skin flayed off. It rides through the countryside destroying crops, killing travelers, causing floods and plagues and generally being a harbinger for all things bad. How do you defeat this monstrosity? Fresh water, and burning seaweed. The Nucklavee fears freshwater, so much so that it cannot cross a stream, and hides in its oceanic lair during the winter storms. Likewise, it finds the smell of burning seaweed intolerably offensive. However, don't provoke the Nucklavee, especially with taunting or burning seaweed, as whenever the Nucklavee is offended, it tries to literally kill all of the horses in the Orkneys with a hideous disease called "Mortasheen."


 * Werewolves have their share of weaknesses, too; earlier legends provide ones such as having an iron bar thrown over their head, drawing three drops of blood, or having their name announced one to three times.

The popular weakness to silver is a relatively new invention. It often comes with an immunity to anything not made of silver. Most werewolves that don't have the silver weakness can be killed by any type of weapon, including silver.


 * Basilisks. Okay, they can kill you if you look directly at them, or hear their voice, or if you touch them, or it breaths on you, but guess what? They can be killed instantly by the crowing of a rooster, and their powers don't work on weasels.

In some legends, Basilisks are also weak to themselves. There are stories of men killing a basilisk by wearing mirrors sewn into clothing.
 * Trolls. Yeah, they can rip you limb from limb with their bare hands, but a little sunlight turns 'em into inanimate rocks.

One good way to trick a troll into watching the sunrise is to challenge them to a game of riddles: no troll can resist such a challenge. But beware--according to the legends trolls are extremely good at riddles, and if you decide to give up before dawn then they celebrate their victory by eating the loser.
 * Many of the oldest portrayals of Satan, the ostensible antagonist to God, has him easily outwitted by peasants and driven away by holy symbols (such as a scapular).
 * Invoking the name of Jesus is also supposed to drive him away--for people who don't believe in the divine authority of Jesus, this seems like a Weaksauce Weakness, but attempting an exorcism is not recommended for the lay believer. To illustrate, The Bible tells of a pair of unbelieving conmen who try an exorcism via the "magic words" "I command you, in the name of Jesus, whom Paul preaches, to come out!" The demon's response: "Jesus I know, and Paul I've heard of, but who are you guys?" and has the possessed man beat the crap out of the conmen.


 * How many mighty gods/beings have been defeated by a mere logical quibble with their own rules? Ditto for evil Artificial Intelligence.
 * When Baldr/Balder, the son of Odin, was born, his mother Frigg made all living things vow not to be able to hurt him. The only living thing that didn't make this promise was mistletoe, which would be fatal to him. So of course, Loki, the trickster god, goes and gets an arrow tipped with poisonous mistletoe and shoots it at Baldr, killing him. Baldr's death would start a chain of events that led to Ragnarok (see further below for the Devil Survivor example).
 * Achilles was the greatest of the Greek Heroes. When he was born, his mother dipped his body in the river Styx (or into a fire, depending on which version of the story it is) so that he would be invincible. The only part of him that wasn't affected was his heel, which was where she held him. Given that the trope Achilles Heel is named after him, you can guess what happened to him eventually. However, some of the myths indicate that he was shot with arrows poisoned with hydra venom, the same ones that killed Hercules, which deflects the weaksauce bit. (If he can only be killed by shooting him in one really hard-to-hit spot with arrows dipped in a poison that, even diluted, could bring down a demigod, then that's... actually a very minor weakness and not weaksauce at all!)
 * It should also be noted that Homer's depiction of Achilles does not appear to include the tradition of limited invulnerability. When Achilles takes the field in the later books of The Iliad, a spear (thrown by a mid-level mook) grazes his shoulder and draws blood.
 * In folk tradition, salt is often used to repel evil. It was said a circle of salt could protect one from witches, that salt over your doorstep would ward off ghosts and evil spirit. Salt was often seen as a symbol of purity, especially in its uses: Salt is a conversation agent after all, and salt-cured meats don't spoil. Salt as a purifier appears in Shinto (Where it is used as a ritual purifier and small mounds of salt can be used to repel evil spirits) and Christianity (where it is used before mass and to consecrate a church).

Anime and Manga
"Pride: Appearances can often be deceiving. Isn't that right, little alchemist?
 * Tobor, the Eighth Man, recharged his powers with an inhalant stored in small, thin, white tubes that he carried in a cigarette case. When the bad guys allowed him "one last smoke" before executing him, this was great; when he was having a fight where kids could see him, he worried about setting a bad example by appearing to smoke.
 * In One Piece, anyone who's eaten a Devil Fruit gets amazing powers, but they all share one weakness; the inability to swim. At all. If they are so much as half-submerged in water of any kind, they become paralyzed (and for many, their powers stop working). Which is kind of a problem, seeing as how many of the encountered Devil Fruit users are pirates or marines in a world that's ninety percent ocean.
 * Depending on the situation, basic hypnosis (such as Jango's ring or Ms. Goldenweek's emotion-altering paint) serves as one of the weaknesses for Monkey D. Luffy, the protagonist. Due to his simple-minded nature, he just won't have to sense to turn away, which makes him helpless and left to the devices of his enemies.
 * Water is actually a much greater weakness to Sir Crocodile, as he is a man who can turn into sand; if water strikes him, the sand "sticks together," and he is rendered unable to turn into sand at all, thus leaving him fully open to attack. He has a natural defense in that his sand powers extend to causing alarmingly fast dehydration with direct skin contact. In addition, he has the good sense to not only do his villainous business on a relatively large island, but on a desert island.
 * And to use the Dance Powder, not only to frame the king in an effort to overthrow him, but also to stop it from raining in the town he was using as a base.
 * Blackbeard has one of the most powerful abilities in universe. He can wipe out entire towns in seconds, shoot the debris out like cannon, and negate Devil Fruit powers. But he can't dodge anything. While most Logia-fruit users can have attacks pass right through them, Blackbeard is quite the opposite, making any physical attack super-effective.
 * The specialists, the Paper Sisters in Read Or Dream can telekinetically manipulate paper... unless it's wet. This was not a weakness for Yomiko Readman, who is shown on camera manipulating paper while underwater. This is actually explained in-universe. The Paper Sisters' powers are essentially imperfect clones of Yomiko's, artificially created by Dokusensha; which is why they are weaker and more specialized/limited. Water naturally disrupts the structural integrity of paper, and their inferior powers are not sufficient to maintain it the way Yomiko can.
 * Super Dimension Fortress Macross has an alien attack force made up of gigantic Scary Dogmatic Aliens who are a proud warrior race do a mass Mook Face Turn because of... singing. And souvenirs. In fairness, it does make sense in the story (at least as much as War of the Worlds Martian's being vulnerable to Earth's diseases) and is perhaps one of the best logical conclusions to a typical alien's Planet of Hats treatment. The aliens have no culture to speak of other than fighting, so when exposed to humans and their culture in the form of songs and interacting with the other gender after sending a team of spies to the SDF-1, typical Zentradi start feeling emotions, questioning their purpose, and becoming similar to humans. Because of this, their entire fleet gets deemed "contaminated" by the unexposed Zentradi and programmed for destruction. In the face of this Enemy Civil War, they wisely choose to ally with the humans. Still, it doesn't quite wash away the faint air of ridiculousness when Minmay's singing becomes an offensive weapon to unbalance the unexposed Zentradi in their attack.
 * Those who consider Minmei The Scrappy half-jokingly argue the Zentradei were distracted by her singing because it was so bad in the Robotech dub.
 * Taken to even greater extremes in Macross 7 where the spirit draining Protodevilins's only weakness is actually the energy produced by music. It produces a spiritual energy "too pure for them to absorb" and regenerates the lost energy in those drained by them.
 * The use of Minmei's voice as a weapon is actually short-lived: while the Zentradi were initially too distracted to react, as soon as the heroes opened fire they started firing back. The real decisive weapon in that engagement was Minmei kissing Kaifun: the Zentradi were so disgusted they stopped fighting effectively, trying absolutely anything to erase the image from their minds, including firing in the middle of nowhere (a Zentradi heavy cruiser was observed doing exactly this as Hikaru locked his nukes on it) and listening Minmei's songs. Incidentally, Macross 7 shows us that Minmei's registered songs have absolutely no effect on unexposed Meltrandi (the FEMALE Zentradi) that just ignore them (partly because they had the common sense to just jam the frequencies used to broadcast them), but BASARA's songs made them groupies the very moment he managed to get them to hear him. It baffled a UN Spacy higher up, who had assumed the Meltrandi would just jam the broadcast (both times the Minmei tactic had been seen used had been with broadcasts the enemy didn't jam for a reason or the other).
 * They could also be paralyzed by kissing.
 * In Rosario to Vampire, vampires are considered the high end of the monster scale, but the fact that you can pretty much take a vampire down with a glass of water kinda puts a dampener on that idea.
 * Though, you'd have to be of werewolf speed to even consider hitting them with the stuff in the first place.
 * Vampires are ironically said to have the most weaknesses compared to any other monster. Things like silver would also do them in.
 * The titular hero(ine) of Ranma 1/2 can be incapacitated by the mere sight of a cute little kitten. However, those who attempt this should note to apply said weakness quickly and forcefully -- prolonged, intense exposure has a tendency to backfire. Thanks to his Gender Bender curse, cold water can also count as a weakness. Technically. Ranma's female form has less strength and reach than his male form (though the anime is explicit that Ranma's speed is boosted in this form, so it's more of a trade), but s/he can still pull off all of his/her normal attacks. Based on a character with an identical curse, it's also possible that being in female form weakens his Ki Attacks.
 * His fiancee Shampoo and his main rival Ryoga Hibiki have an even worse case of the water weakness than Ranma does; Jusenkyo made them become a little kitten and miniature pig respectively when splashed with cold water. So they go from incredibly powerful fighters to harmless little animals whose only recourse is to run or hide until they can get some hot water. Genma Saotome, Ranma's father, pretty much subverts it; his panda form loses little, if any, speed and agility while gaining in strength and toughness due to the increased bulk. Mousse, meanwhile, seesaws between subverting this trope and playing it straight with his duck curse; while it is much smaller, weaker and can't use his physical attacks, it can fly and he's still capable of throwing barrages of knives, darts and bombs in it.
 * And a non-water version applies to Happosai, who is such a Dirty Old Man that his perversion becomes his own Achilles heel. If there is a fight serious enough, or a reward great enough, that he can't be immediately distracted from whatever he was doing by the sight of girls in skimpy clothing, bare cleavage or a bra, it hasn't come up in the series. He can even be lured right into dangers simply by tossing a bra in the right place.
 * My name is Yutaka Takenouchi, and I have only one weakness ... I am VERY susceptible to motion sickness!
 * Natsu from Fairy Tail is Made of Iron, he can breathe fire and cause massive property damage simply by punching someone, but he too suffers from the ignominious suspectibility to transportation. At least once it was actually exploited to defeat him in battle.
 * This motion sickness seems to extend to being carried by people, as well. He's perfectly fine being taken to flight by Happy the cat, however, reasoning that Happy isn't a vehicle. So Lucy is?
 * According to Rogue, ALL DRAGON SLAYERS suffer from this.
 * In Bleach, Espada #9 Aaroniero can't use his shapeshifting when in sunlight. Though he can still use any of his other 30,000+ powers (not that he does before getting killed, but he had the option).
 * To make matters worse, he lives in Hueco Mundo, which has no natural sun. His boss builds a fake one for no discernible reason.
 * Fullmetal Alchemist: In the manga and second anime, Pride can project razor-sharp tentacle-like shadows from his body. But he can only project them where ordinary shadows could be cast; complete darkness renders him unable to attack and bright lights can cut off his tentacles. Granted, he is still near immortal even when he can't attack; in a way he is both the most powerful and the most vulnerable homunculus.
 * A common mistake for people in the series is to assume that Flame Alchemist Roy Mustang is useless when wet (or without his gloves). This is only true to a certain extent, and let's just say he earned his rank.
 * A combination of this and Berserk Button: Insulting Ed's height, while entertaining, has a tendency to impair his judgement as he blindly charges the enemy. This is mostly Played for Laughs, although Pride uses it once to get an edge in combat.

Ed: Grk!


 * Pride attacks*"


 * In Naruto, Konan of the Akatsuki is, like all members of that group, very powerful. Yet her paper-based techniques can be completely nullified by spraying oil on her to make her stick together (a technique one human ninja and some summoned toads have), although water can release her.
 * Adam Blade from Needless has a weakness for little girls, and usually ended up getting his butt kicked because of this. Though later in the manga his weakness had developed from mere lolis to naked lolis. In the other hand, his love for lolis can temporally boost his strength and saves him from a Lotus Eater Machine, so it's subverted.
 * Emperor Nightmare, the leader of Nightmare Enterprises (Holy Nightmare Co. in the Japanese version) in the Kirby anime, is weak against AND afraid of


 * The Dai Gurren in Tengen Toppa Gurren Lagann is a walking battleship...that is not designed to go on water. A battleship that isn't designed to go on water.
 * In Ah My Goddess, Urd is put to sleep by Enka music, traditional Japanese ballads. When someone tries to take advantage of this fact, she just pops in earplugs.
 * Mara is weak to rock music; it causes her to dance uncontrollably.
 * Saiyans, a race of savage and brutal warriors from Dragonball Z can be easily neutralized by grabbing their tails. They can be trained to overcome this weakness though.
 * The only way to defeat Chaozu's psychic attacks is to break his concentration. Krillin does this by asking him extremely difficult math questions. Like 9 - 1.
 * After that his teacher the Crane Hermit immediately gave him remedial math lessons.
 * Apparently, whistling around Piccolo, or any Namek can really incapacitate them. This becomes a plot point in the DBZ movie Lord Slug where Piccolo
 * In the manga Fukashigi Philia, the villain Shidow is extremely fearful towards water to the point if he gets in contact with it, he will go berserk and have his abilities neutralized.
 * From the manga Kenichi the Mightiest Disciple, we have Akisame Koetsuji, the Jujutsu Philosopher. Master martial artist, a doctor so skilled he can raise the recently dead, and master of a bazillion and six other fields. He's one of Kenichi's six super-powerful masters... and green peppers make him so ill that he can be held at bay simply by hanging one outside his door.
 * Kinnikuman is weakened by milk. Though after he goes insane during his match against Curry Cook and drinks the stuff, it becomes apparent that he just thinks it's disgusting.

Comic Books
""Sounds like the deal of the century, Flipper! And everyone says I'm the crazy-""
 * Almost every Green Lantern from The Silver Age of Comic Books onward had yellow as his main weakness. Any criminal could waltz past him by wearing a yellow suit and stealing only gold, and shoot yellow painted bullets from gold plated guns. There have been various explanations such as programming bugs or a deliberately-induced Fantastic Fragility, but the currently-accepted explanation is a combination of yellow representing fear, the enemy of the Heroic Willpower energy the Lanterns wield, and the fact that a yellow fear monster had been imprisoned in the Central Battery, tainting the power source. The weakness can now be recognized and overcome, and adaptations tend to downplay it into almost nothing.
 * More recently, Frank Miller parodied the hell out of this in All Star Batman and Robin The Boy Wonder. Before confronting Green Lantern, Batman and Robin paint an entire house, and everything in it, yellow. Then they put on yellow costumes. Then they paint their exposed faces yellow. When GL comes over, Batman goes so far as to offer him a nice refreshing glass of lemonade, while Robin eats some lemon ice cream. Hal was not amused. Readers were.
 * The original Green Lantern was almost as bad -- his weakness was wood. Since so few people knew it as later Green Lanterns became famous, however, he in many cases seemed more powerful than the new Green Lanterns because, for example, the Sinestro Corps yellow power rings couldn't even make him flinch.
 * This was parodied in the Justice League Golden Age Affectionate Parody episode "Legends", with his stand-in version "Green Guardsman", who had a weakness to aluminum. Either way, you've got a superhero who could appear on the news after having been beaten to death with a baseball bat -- and considering that one of his foes was the Sportsmaster, who did wield a baseball bat... it's pretty darned weaksauce.
 * It didn't hurt that wood, while very common when Alan Scott first hit the scene, had become rarer in civilization by the time The Silver Age of Comic Books hit. Villains in The DCU tend to decorate in metal, plastic, and Zeerust by then, which means even less to block that strange ring with.
 * This actually becomes a problem for him in the Elseworlds story Kingdom Come. Like most of the other original heroes, Green Lantern Alan Scott's powers have progressed to a ludicrous level - he keeps watch over the Earth in a massive emerald Space Station, constructed himself a suit of impressive armor, and carries around a sword made out of pure energy - all from his power ring. None of it helps very much against Green Arrow in the final battle, since this Oliver Queen's arrows are made out of wood.
 * This was the main reason that Solomon Grundy was such a threat to Alan. Being drowned, soaked in and resurrected in a swamp, his body was filled and covered with plant matter, rendering the ring all but useless in directly affecting Grundy (Swamp Thing even explained that Solomon Grundy was now a plant-based elemental of sorts like he was).
 * The Elseworlds story Superman/Batman Generations Handwaves the odd Green Lantern weaknesses by having the Guardians explain that all weaknesses are mentally-imposed. Alan was weak to wood because a thug surprised him with a baseball bat and he assumed the ring didn't work against wood, while Hal was told that the rings were ineffective against yellow and thus added the weakness himself. Kyle, who gets his ring without hearing the explanation, lacks any weaknesses. (This is not, to be clear, how it actually works in continuity.)
 * One Green Lantern story subverts this, however. A yellow robot attacks the Justice League. GL responds by picking up mud from a nearby swamp and dropping it over the robot's body, completely coating it. With the yellow hidden, he quite easily rips it open.
 * The yellow weakness was especially weaksauce in The Silver Age of Comic Books because of the fact that every other villain seemed to emit some kind of "infra-yellow radiation", contain a "yellow compound", be surrounded by "invisible yellow" or have some other completely ridiculous piece of pseudoscience in place to stop Green Lantern destroying them in five seconds flat. For those curious: "infra-yellow", in a sane world, translates as  .
 * This was a very situational weakness, as sometimes Hal's constructs interacted with Sinestro's yellow ones, creating a blue haze that negated both. Other times, Lanterns responded by using variations of Car Fu with whatever they could throw at an opponent, or even remembering that an opaque construct around a target meant only green light got through -- and turning any yellow inside the construct into green due to reflective properties of the color yellow.
 * And then there's the Blue Lanterns, who are incredibly powerful even by Green Lantern standards, but can't use anything but the bare minimum of their powers unless a Green Lantern is in the vicinity.
 * Isn't green partly yellow?
 * Only when dealing with pigment. When mixing different colors of light together, a combination of Green and Red is perceived as yellow. However, the yellow band in a rainbow is light of a completely different frequency/wavelength than either green or red.
 * According to Word of God from Greg Weisman, Green Lanterns in Young Justice do not have a weakness to yellow and original Green Lantern Alan Scott did not have a weakness to wood either.
 * One version of Ocean Master, Aquaman's arch nemesis, gets his powers from a magical trident he traded his soul for, and when he isn't holding it he feels intense pain. Even The Joker says that this is a pretty Weaksauce Weakness:


 * In the earlier Aquaman comics, the King of the Sea himself, for all his prowess in the ocean, could not be out of the water for more than an hour or he'd dry out and die. He probably got this from Namor the Sub-Mariner, whom he was initially a Captain Ersatz of.
 * Power Girl went through a single-issue Dork Age where she could be hurt by any "natural, unprocessed material", including the proverbial sticks and stones. This for a character who's on par with Superman. The negative reaction from readers caused it to never appear again. It was just that weak.
 * During her JLE days she was also allergic to diet soda, causing fits of anger.
 * Empowered is a self-admitted Fan Service exploration of this. The main character is a curvy babe who derives her powers from an extremely skintight suit, that's laughably easy to rip and weakens her powers when damaged. Her tendency to end up naked (or nearly so) makes her the laughing stock of the local superhero community. Her tendency to get Bound and Gagged while doing so makes her living Fetish Fuel.
 * The suit's ability to be torn seems to fluctuate with Empowered's confidence level. Since she has zero self-confidence anyway and the regular humiliations related to her crappy suit only compound them, it is very rare that she has the confidence to use her powers properly. But when she does, she's a one-woman army.
 * Emp doesn't get the distinction of the weakest-sauce weakness, either... That honor goes to The Lash, a supervillain with a debilitating phobia of fabric stores due to childhood trauma. (He likens it to being put in a sensory deprivation tank.) Also, while not a weakness per se, on two separate occasions a supervillain has shown themselves to be unable to tie a knot, which is a vital career skill in this setting.
 * Think about it. Being the only villain in the world not being able to tie up the one superhero with a reputation for always ending up bound and gagged by the lowliest of thugs.
 * The Daxamites in the DC Universe are almost exactly like Kryptonians when under a yellow sun. However, exposure to lead is fatal to them, even in trace amounts, and (especially true in the Silver Age) being moved away from lead doesn't cure them. Once the poison is in their system, it's not going anywhere. A notable instance of this example was when one of Superman's recurrent enemies/reluctant allies, Paragon, took out three Daxamites with a machine gun while they were distracted by their Jerkass A God Am I power trip.
 * Martian Manhunter has a ridiculous amount of powers, yet he had weakness to fire, making it quite easy to disable him. This because he saw his entire family--and species as a whole--die in a psychic plague that manifested itself as fire. He then buried the bodies of everyone on the planet. This makes his pyrophobia a form of post-traumatic stress disorder. The first attempt to remove this weakness accidentally unlocked his Super-Powered Evil Side.


 * Prism, a member of the X-Men villain group the Marauders, is a truly pitiful example that combines this trope with What Kind of Lame Power Is Heart, Anyway?. His mutant ability is that he is made of a crystal that can absorb and redirect light energy (like a prism) and is no more durable than glass. Yes, he is made of glass. His weaknesses include any sort of impact. Two of his four deaths (yes, he has died often) involve being thrown into a wall and being shattered by bullets.
 * The greater the power, the weaker the sauce! Marvel's latest and most prominent Superman pastiche is theSentry, a "golden guardian of good" who's pretty much as powerful as he lets himself be. However, he's also agroaphobic--he can't stand being outside. If you also so much as remind him of his little Dark Side problem, he'll fly off to Saturn and cry. Or revert to human form. Or, if he's really unlucky, let the Void out--and suddenly things will look a whole lot better for the bad guys.
 * One fancomic actually has him carrying around his entire living room whenever he wants to go anywhere.
 * Iron Man once defeated him by forwarding his mail, more or less.
 * This was once parodied in the British comic, The Beano, in which the character Calamity James is rescued by a superhero and offers him a Jelly Baby by way of thanks. Guess what the hero's one weakness is!
 * Mr. Mxyzptlk is so powerful that he has no natural weaknesses. To make his fights with Superman more challenging, he gives himself one. Which one does he choose? Saying his own name backwards.
 * Used hilariously in the animated series, with an entire episode consisting of Superman using clever and creative ways of exploiting Mr. Mxyzptlk's "weakness", often without having to use any sort of super powers at all.
 * Mxy's biggest weakness is that he's a gullible idiot.
 * Venom. Weaknesses? Fire and loud noise. At one point, he's defeated with nothing more than a lighter. This, of course, varies Depending On the Writer. Carnage shares some of the same weaknesses.
 * Fan-favorite (yet sadly not used, ever) Toxin, Carnage's "child" however doesn't, what it does have is being very child like, (one point it refused to help it's host because he yelled at it)
 * All Symbiotes are vulnerable to intense heat and sound. The amount of their resistance varies depending on the Symbiote in question(Carnage's resistances dwarf Venom's) and, on a more meta-note, as mentioned Depending On the Writer.
 * Though it's actually justified in that the symbiotes come from a world with no atmosphere, and thus have no antural resisance to extreme tempreature or noise because they'd never naturally encounter them. Even a few generations with them around and the weakness is bred away quickly.
 * Marvel's Inhumans, genetic superhumans who have advanced technology and a civilization predating regular humans' by millenia, are done in by... pollution and germs.
 * The Darkness, phenomenal cosmic/demonic power. But can't operate under a 60 Watt light bulb.
 * DC Comics also had Firestorm, whose weakness is organic materials. All of them. He can't affect them with his power, or he'll suffer painful consequences. So...he could be foiled by a stick. Or a leather wallet.
 * A recent version of Firestorm was beaten because he published a scientific paper on how his own powers worked. And Lex Luthor read it. "Oh no" indeed.
 * Firestorm needs to merge with someone in order to use his powers. If the merge happens too long, his powers eat his partner.
 * In one of his appearances on Super Friends, he was rendered helpless after being sprayed with plant food. Even their version of Aquaman wasn't as lame.
 * In Firestorms case, his weakness was probably imposed to prevent the Nightmare Fuel implications of his powers being used on living people and animals. Since Blackest Night eventually provided us with a very memorable example of just how scary his powers could actually be, maybe it was for the best that writers watered him down early on.
 * Although it's since been removed, Eclipso - DC's god of darkness - could be dispelled from his human host by a camera flash.
 * Gladiator, Praetor of the Shi'ar Imperial Guard. Strong enough to shatter planets. Able to fly at many times the speed of light. Can withstand the heat of a star or the blast of a supernova. His eyes can emit beams of unimaginable heat, and they can see particles on a subatomic level. Truly a being of such infinite power can only be defeated by...making him feel bad about himself.
 * Somewhat justified in that his powers are explicitly psionic/mental in nature. If he believes that they won't work or that he can't complete a task with them, they won't work and he won't be able to complete that task. This means you don't actually need a weapon powerful enough to beat him, only something which you can convince him is a weapon powerful enough to beat him, which Rocket Raccoon exploited.
 * Another parody--Super-Ace, an alternate Ace Rimmer from a superhero universe appeared in one Red Dwarf Smegazine comic strip. While he had the full array of Flying Brick powers, his one weakness was ... human flesh. So an ordinary Mook could punch him.
 * Storm, of the X-Men, has complete control of the weather almost pushes her into God Mode Sue territory: in practice it gives her flight, superspeed, and the command of electricity, water, cold, and wind. So what's her weakness? Claustrophobia. If a writer wants to take her out of a battle, all they need to do is drop some rubble on her--and sometimes not even that much. In her early years, she had a Heroic BSOD when a villain only mentioned a word that made her think of enclosed spaces. (These days, trying to stick her in an enclosed space just makes her mad.)
 * The laughably silly Silver Age DC villain Ten-Eyed Man was a guy whose "power" was being able to see through his fingertips. Every single battle involving him ended with him being tricked into grabbing something rendering him completely helpless.
 * Zatanna is one of the DC Universe's top magic users, but, because she needs to verbalize her spells, she can be rendered helpless if she's made unable to speak, which led to her being frequently (especially in her early days) Bound and Gagged (not that there's anything wrong with that). Recent comics have come up with creative ways to work with this, such as a recent Batman comic where the Joker shot her in the throat so she couldn't talk, but she managed to write a spell in her blood, or something.
 * Despite having an incredibly powerful sonic scream, gagging Black Canary could effectively disable it, despite the fact the Canary Cry theoretically should be able to break through any cloth. That too, has decreased in recent years, although Deathstroke found an, “interesting” way to silence her in an issue of Green Arrow.
 * Fay Moffit, the second Spellbinder (the original was a third-rate Batman villain who was Fay's lover, whom she murdered when he turned down power from Neron and took it for herself) has the ability to create very realistic illusions. However, because her eyes are needed for this, simply blinding her in some way is enough to disable her power.
 * When he first appeared, Loki of The Mighty Thor had one-he couldn't use his powers when wet/in contact with water. Against Thor, who could easily make it rain. No wonder this is ignored now.
 * Plus, Loki's a Frost Giant. A race that lives on a snow-covered world and fights with ice. This weakness became Fridge Logic after that came to light.
 * The sword in, umm, The Sword grants whomever touches it serious Super Strength, enough Super Speed to run on water and deflect bullets, and a powerful healing ability that can close gaping chest wounds and reattach limbs. Unfortunately, these only last for as long as the user maintains physical contact. Put it down to eat a sandwich or go to the bathroom and you're mortal again. At one point, protagonist Dara drops in the middle of a super-strength high jump (a natural reaction to being shot) and suddenly finds she's not landing, she's falling. Worse,
 * The first story of the 2011 relaunch of Swamp Thing features a kid villain named William Arcane. William's connection to the forces of Death (or The Rot) allow him to control all dead or decaying matter. This gives him immense power. The only problem is his fatal allergy to chlorophyll.
 * The story "The Day Red Turned to Green", in issue #85 of Tales of the Unexpected, featured giant mushroom-like aliens that could be harmed by anything red. The main character found one of their "absorbo-sponges" while spelunking, and anything red that he passed while carrying it turned green.

Fan Fiction

 * Not even a God Mode Sue like Ronan of Naruto Veangance Revelaitons is immune, as he and suffer great pain and are incapacitated if they hear music they don't like (Top 40 music and music the author likes, respectively) or something that goes against their religious beliefs (Bible verses and the works of Richard Dawkins, respectively). Madara is also allergic to cats, enabling him to get beaten up by some of his Catgirl Mooks after Ronan has sex with them, resulting in their switching to his side.

Films
"Megamind: Your weakness is copper!? You're kidding, right?"
 * The Wizard of Oz gives the trope-codifying example: the Wicked Witch of the West melted when splashed with water.
 * Freddy Kreuger, the nigh-unstoppable Humanoid Abomination that can kill you in your dreams has a weakness to, of all things, people not believing in him. This becomes far funnier when you realise that his weakness is basically the same as Tinkerbell of all things!
 * The aliens in Signs. It's hard to feel threatened (retrospectively) by creatures which will dissolve in an April shower or corrode in a particularly humid breeze.
 * In Shyamalan's earlier film, Unbreakable, he also used water as a weakness for the main character. In that case, though, it wasn't that he was especially vulnerable to water, but rather he was just as susceptible to drowning as a normal person. If he drank something too quickly he would choke and if he was submerged he would succumb to drowning just like everyone else--though it was theorized that the dense bone and muscle that made him unbreakable also made him unfloatable (or the character simply couldn't swim).
 * It was also a psychological weakness: he had almost drowned once as a child (probably due to the a fore mentioned bone density), an event so traumatic he blocked it from his memory. That would make anyone nervous around water, even if they couldn't remember why.
 * There was also a complicating factor in the scene where he ends up almost drowning in a swimming pool. He's tangled up in a big piece of fabric, which would give anyone a bad time while in water.
 * Shyamalan probably got the weakness idea for Signs from Invasion of the Saucer Men, whose aliens were melted by light. There is nothing lamer. Especially considering they were done in by
 * The Bioraptors (also called 'Demons') of Pitch Black had a similar weakness to light. Though this actually worked, as most of the movie was during a solar eclipse and they broke their flashlights. Oddly enough, the creatures are shown moving about in the light, albeit cautiously, before the eclipse. Compare this to later on, when a lighter is enough to make them run away...
 * The same thing appeared in Attack of the The Eye Creatures. Although, in this case, it was more because They Just Didn't Care (and because it was an almost word for word remake of Invasion of the Saucer Men).
 * Also happens in The Mole People; in which a lost colony of ancient Sumerians living Beneath the Earth had adapted to their lightless conditions to the point where our heroes could kill them with a flashlight.
 * In the movie version of The Day of the Triffids, the titular monsters were melted by sea water. Nearly as lame. In the original novel, ironically, flame-throwers are among the most effective anti-Triffid weapons.
 * Your Mileage May Vary on whether FIRE is a Weaksauce Weakness, considering how many things are affected by it.
 * The Tenctonese in Alien Nation (the movie as well as the series) are harmed by salt water. Seawater is like acid to them. They live mostly on the Californian coast; while they do develop a tolerance to it, though direct exposure is still harmful to them.
 * There is a slightly funny moment when the police find the partially-dissolved body of a Newcomer washed up on the beach. When asked how they were able to identify him, they simply shrug and show his soaked wallet. All his clothes were, naturally, fine too.
 * In the Disney Channel movie Up, Up, and Away, the weakness of the superhero family is aluminum foil.
 * In SYNGENOR, the titular creatures were created to be the perfect soldiers for a war with the Middle East. They don't need to eat or sleep, are immune to most weaponry, and reproduce every twenty-four hours. Their only weakness? Water is like acid to them. It's somewhat hard to be afraid of a super soldier that can be defeated with a super soaker. Or, if worst came to worst, by peeing on them.
 * In the Dead Gentlemen Productions (of The Gamers fame) running Demon Hunters series, Duamerthrax the Indestructible is a walking brick that is, well, all but indestructible. He's an "earthwalker", a demon said to have been kicked out of hell for being too mean. Unlike other monsters and demons in the mythos, he's not susceptible to ordinary injury. He can literally eat the round of a large-caliber revolver jammed in his mouth ("Mmm! Nice 'n' leady!") casually regrows limbs after being dismembered, and generally shrugs off what few injuries he even takes while making terrible puns. So what's the convenient balance? We're told that every earthwalker has a weakness to some substance, "a plant, metal, anything". Duamerthrax's turns out to be mint. Being shot repeatedly at close range with numerous handguns does little more than inconvenience him, but the breath of someone having just used breath spray causes him intense pain, water-guns full of mouthwash can inflict serious harm and.
 * Mars Attacks (Film)!. The Martians' weakness is hearing high-pitched yodeling, such as in the song "Indian Love Call" by Slim Whitman, which causes their heads to explode.
 * The Tomatoes in Attack of the Killer Tomatoes had the same weakness, in the form of a song called "Puberty Love".
 * Imhotep in his incomplete form The Mummy Trilogy was immediately chased away when a cat is in his presence, because they guard the Underworld. Naturally, the heroes never did anything to exploit this weakness, such as by putting cats in the room full of the people he needed to kill to stop being vulnerable to cats.
 * Rendered especially silly by the fact that if you've ever been to Egypt, you'll know that there are stray cats absolutely EVERYWHERE, meaning that all the heroes had to do was go downstairs and grab some.
 * Rick did place a cat in Evey's room, thought it seems to have slunk away to a corner where it wasn't much use. Still, when Imhotep came to call, all Rick had to do was hold it up in a pseudo-menacing fashion. This was enough to drive Imhotep away. Soon after, the mummy regained his powers completely and lost that particular weakness. This still doesn't explain why the other people he had marked out as victims hadn't kept cats on hand.
 * From 1966 superhero parody Rat Pfink A Boo Boo: "Remember, Boo Boo, we have only one weakness... bullets."
 * Like the Dalek example given below, in the 1987 movie Robo Cop, the killer robot ED-209 chasing the titular character was taken out of play simply by trying to chase Robo Cop down stairs that its chicken-walker legs were ill-suited to negotiate.
 * In an Homage to The Wizard of Oz, Death in Six String Samurai is killed when squirted with water.
 * Derek Zoolander can't turn left until his Big Damn Heroes moment. (Though continuity nitpicks will note that he does turn left (relative to himself, though not the camera) while in disguise while trying to retrieve Maury's computer.)
 * The Spiderwick Chronicles provides a literal weaksauce weakness: Tomato sauce is corrosive to goblins. (This was not in the original book.)
 * The Blue Meanies are repelled by positivity in any form. This doesn't work out so badly, though, since their entire arsenal is built around the proliferation of depression and despair, but it does still leave them vulnerable to music.
 * Bolt, of the movie of the same name, thought his super-weakness was styrofoam.
 * Mystery Men, Invisible Boy's weakness was anybody looking at him while he was invisible.
 * The Supercop in Super Fuzz has super speed, super strength, invulnerability, telekinesis and so on, but he completely loses his powers when he sees the color red (probably a nod to GL and his vulnerability to yellow): a red traffic light, a red flower, a red ribbon, and he's harmless.
 * The Psychlo homeworld of Battlefield Earth can be blown to (relatively) tiny bits with a nuclear explosion. You'd think that is substantial enough to bypass the Weaksauce bit, but remember that this is a PLANET. It'd be like a human exploding in a smear of gore after stubbing their toe.
 * The movie Sleepwalkers had monsters that were Made of Iron, except for when scratched by house cats.
 * In Monty Python and The Holy Grail, the Knights Who Say Ni can't stand to hear the word.
 * As is the usual with horror movie monsters, the 1973 Blaxploitation movie titular character Blackenstein was Immune to Bullets, fists, and blunt objects--traits which, when added to his Super Strength, seemingly made him all but unstoppable. What is it that finally laid the mighty monster low? The primal forces of nature themselves or divine intervention? No. The police sicced the hounds on him. That's it. Doberman Pinscher fangs trump bullets, apparently.
 * Mad Max Beyond Thunderdome. Blaster is the immense Dragon to Master. According to people who want him dead and have been hunting for the right assassin to get the job done, "He can kill most men with his breath." His weakness: he can't stand high pitched noises. Max discovers this when the car alarm on his vehicle renders Blaster into a writhing, screaming, mess- and promptly figures out that his old police whistle can have the same effect.
 * The undead mutant warrior things from the 80's flick Neon Maniacs are virtually invulnerable except, like many other things on this list, they can be dissolved with a squirt gun.
 * The goblins from Troll 2 are defeated when Joshua eats a double-decker bologna sandwich in front of them during the film's climax. They literally can't come within 20 feet of you after you eat 2 bites of bologna.
 * in Megamind when Metro Man has a weakness to copper as part of . This is even lampshaded by Megamind:


 * Copper is pretty common, so Megamind really should have realized . Especially since he grew up with Metro Man and would have seen him handle things like pennies or batteries.
 * Ernest Scared Stupid's titular monsters are these trolls, who legend speaks of them being weak to... milk.
 * In Lair of the White Worm, a vampire's natural enemy is the mongoose due to vampires in this universe being snake-people.
 * Also, playing the bagpipes puts them in a trance.
 * In Hook, the Lost Boys exploit Captain Hook's fear of the sound of ticking clocks, which they attribute to Hook's memories of being pursued by a clock-swallowing giant crocodile. Subverted when Peter points out that Hook can't really be afraid of the crocodile,  Counts as Fridge Brilliance, as the original Peter Pan could never have made that connection before he had the chance to grow up himself.
 * Superman IV brings us the horror that is Nuclear Man who, for reasons unknown, is powered solely by the sun. The minute he is out of direct sunlight he stops dead. Even if he's in a well lit room but slightly in the shade then he's next to worthless. This is especially pathetic when you consider that, in canon, Superman's own powers are ultimately derived from sunlight, but *he* doesn't power down in the shade.
 * In The Traveler, the only way to counter Mr Nobody is actually by, which will make him lose powers and become vulnerable to physical attacks. Kinda makes sense for him to conceal his identity throughout the film.
 * Played for laughs in Evolution, where the aliens' critical weakness is to dandruff shampoo.

Gamebooks

 * The Darklords of the Lone Wolf gamebooks are crippled by clean air and can only unleash their full strength in toxic habitats; making them the polar opposite of Captain Planet. Half the reason they waged a centuries long campaign ruining Magnamund (the other half being that they are Always Chaotic Evil embodiments of evil) is  to make the world a paradise for themselves. It should be noted that even in their weakened state they can still put up a good fight with their mastery of Black Magic and immunity to conventional weapons.
 * In one story arc, the Darklords developed a magical engine that would allow them to retain their full strength outside their realm. About a dozen of them were in the frontlines of their war when the protagonist smashed the engine, singlehandedly ending their reign of terror.

Literature

 * The Wicked Witch of the West from the The Wonderful Wizard of Oz was done in by a pail of water. This was explained in the book (but not in the movie) as due to her being "dried up by years of evil" but no indication was ever given that water would kill her. The book does mention that the Witch would never go near Dorothy when she bathed because she hated water.
 * This makes said Witch giving Dorothy a bucket of water to do chores with a rather stupid move. Though the fact that the movie is made All Just a Dream allows for a convenient justification.
 * The Wicked Witch is not the only one afraid of water: while Tin Man doesn't melt, he rusts to the point of total immobility - even though he shouldn't.
 * Another Oz-related Weaksauce: the Nome King was an extremely powerful, nigh-invincible subterranean fairy who had armies of nomes... all of them, including him, could be weakened to the point of being killed by eggs. This doesn't look as bad as it seems at first, because there's only one chicken in Oz.
 * The book Wicked, a parallel novel based on The Wonderful Wizard of Oz, explores the Wicked Witch of the West's weakness to its entirety, explaining that since birth, exposing her skin to water hurt her, so she had to clean herself with oil and find creative solutions for things which normally involve using water. When she cries, it's like acid flowing down her face. Weakness to water could be the result of the unexplored concept of being "a daughter of the dragon". Its also implied that if Elphaba had ever come into the fullness of her powers, water would cease to be a true threat to her (at one point she instinctively freezes a lake, allowing her to cross it unharmed).
 * The Musical adaptation of Wicked openly mocks the entire idea of water melting the Witch.
 * The weakness from The Wonderful Wizard of Oz is spoofed in the Enchanted Forest Chronicles, where evil wizards can be melted with water--but only with soap and lemon juice added. The good witch Morwen, on the other hand, explicitly does not melt. It is later theorized that this might be because the wizards never shower while Morwen is something of a neat-freak. Eventually, the heroes refined this into a one word spell with the same effect. One very memorable word, too: !
 * The aliens in The War of the Worlds were killed by.
 * The Martians, in Ray Bradbury's The Martian Chronicles, are killed en masse rather early in the book by a human-induced plague of chicken pox. It's a knowing reference to both American history and The War of the Worlds.
 * The Boggart in Harry Potter seems to be almost an incarnation of this trope. A Boggart will materialize in the form of a person's worst fear (though exactly what that means is debatable). The way to repel one is to forcibly imagine the fearsome thing as something ridiculous, and then laugh at it.
 * Alternatively, the Boggart can't handle trying to frighten more than one person at once, as attempts to materialize into more than one person's fear results in things such as the "half a slug" incident. This is why Lupin advissed his students not to face a Boggart alone (combined with the above reason).
 * Voldemort's inability to understand Love, and The Power of Love, proves to be his ultimate undoing. However, this is less of a Weaksauce Weakness than a Fatal Flaw. Harry does not beat Voldemort because of some mystical aspect of love, but because having reliable friends and allies ultimately gives him an advantage over Voldemort, who underestimates the capacity of others to behave selflessly because he would never even consider doing so himself.
 * In the Sin War trilogy, Diablo, the Lord of Terror and one of the three most powerful evil things in existence, is defeated by a reflective surface. To clarify, Diablo appears as things you fear, and if it's bad enough to scare Diablo, it's pretty bad.
 * Eddings' The Redemption of Althalus featured both one protagonistic and one antagonistic Five-Man Band, both with similar power arrays. The villains included the evil mind-leech Koman, with telepathy and mind-warping abilities... who was defeated when Althalus thought about random numbers. Fractions of numbers, even.
 * Discworld examples:
 * The Auditors in The Science of Discworld III: Darwin's Watch. There are very logical and clearly worked out reasons why chocolate kills them in Thief of Time, due to some peculiar circumstances. In SoDIII, though, it just does.
 * Non-incarnated Auditors can be killed by getting them to say "I", "me", or otherwise admit individuality. Since it's widely known that (a) only living things have individuality, (b) all living things die after some amount of time and (c) any living thing's lifespan is practically no time at all compared to the universe's, any Auditor who admits individuality instantly dies. By the perspective of the rest of them, this isn't much of a loss, since there are more Auditors than there is anything else in the universe and, by definition, any given one of them is supposed to lack any defining characteristics.
 * Much of the plot of Discworld novel Carpe Jugulum concerns a group of "modern" vampires attempting to subvert this trope by developing resistances to the traditional vampire weaknesses.
 * Discworld vampires play this trope in a weird, All Myths Are True way. ALL weaknesses you might have ever heard of apply to SOME vampire, but you may have to do trial and error to find out which ones apply to the particular one who's trying to eat you right now. There are also a few with psychological problems that compel them to do things that directly address their particular weakness (such as the vampire flash photographer who works for The Truth, who has a weakness to bright light, and the one who worked at such jobs as pencil maker, garlic stacker, and whole-sale holy water clerk).
 * Discworld bogeymen are incredibly strong, reasonably nasty, and some of them can teleport to some extent. Their vunerability is that they're ridiculously succeptable to Clap Your Hands If You Believe. If you can get your head under a blanket, then you believe you're safe from the bogeyman and therefore you are. If you can get the bogeyman's head under a blanket, he goes into "existiental shock", since he no longer believes he exists.
 * In Artemis Fowl, fairy magic can be completely stopped by animal fat. That's right, magic that can make you invisible, hypnotize people, heal nearly anything, and in some cases travel through time can be stopped by lard. Praise the Lard!
 * Also not forgetting some of the laws that (most) fairies have to adhere to thanks to some very old, powerful magic-- the most commonly seen are the Ritual for restoring magic (has to be done with an acorn, at the full moon, under an oak next to a bend in the river... or at least to start with. By the second book that's already been thrown out as mere myth.), the 'fairies cannot enter human houses without permission' rule, and by extension, the 'fairies cannot disobey a direct command given by a human eye to eye' rule. Of course,
 * The Haunter in the Dark, the titular monster in a story by HP Lovecraft, is an avatar of the god Nyarlatothep. It's a huge winged and tentacled mass of darkness with a three-lobed burning eye, whose touch will burn the flesh from your bones. However, it's extremely vulnerable to light. Even little light will hurt it, and strong light will banish it. So you can temporarily defeat an avatar of an ancient and evil god with a flashlight!. Temporarily. As soon as the lights are out, it can come back, just as nasty as before.
 * In Worldwar (Literature), the invading reptilian aliens called 'The Race' had an immense weakness to ... ginger. Not only was it an incredibly addictive narcotic, but it also made the females produce sexual pheromones outside of the normal fertility cycles, turning exposed members of The Race into crackheaded sex fiends. When the humans attacked Race-occupied Australia, they used missiles armed with warheads packed with powdered ginger.
 * Even before they discover ginger's effect on the Race females, they find that not only does is it extremely addictive to the lizards, but it also causes them to temporarily feel nigh-invincible - not a good trait for an infantryman, a tank crew commander, or a fighter jet pilot.
 * In L.J. Smith's Night of the Solstice series the Fair Folk-like race known as the Quislai have many advantages, such as immortality, invulnerability, extreme beauty, the ability to throw lightning bolts, the power to travel to places quickly using secret pathways through space, and freedom from nearly all physical limitations. They can't be imprisoned by normal means, as doors and windows will unlock themselves for Quislai, and they can travel through dimensional gateways between worlds without preparation while everyone else requires a special magical amulet to use them. However, the one thing that can restrain them is a thornbranch tangled in the hair. Unfortunately, most Quislai seem too ditzy to think of cutting their hair short or at least avoiding rosebushes.
 * Judges 1:19 in The Bible is often taken by unbelievers and skeptics to argue that iron chariots are a weakness of God; as the King James Version translates it, it reads "And the Lord was with Judah; and he drave out the inhabitants of the mountain; but could not drive out the inhabitants of the valley, because they had chariots of iron." Needless to say, this interpretation is not generally accepted by believers.
 * The great Samson got his Super Strength from Nazirite rituals, and breaking them was his big weakness. He attempted to mask this by making up a bunch of equally weaksauce fake weaknesses, only to kill anyone who actually tried them. He was still stupid enough to tell his true weakness to Delilah, despite her being the only one who knew of his "weaknesses" and therefore the only one who could have told them to his enemies. By the time he'd cut his hair (famously thought to be his sole weakness), he'd already violated other parts of the Nazirite rituals, such as drinking alcohol and handling dead bodies. Cutting his hair was the last straw, so to speak.
 * The Death World creatures of Fragment are averse to salt water and avoid it (it's toxic to them for some reason), which is presumably what's kept them confined to Henders Isle. This is discovered accidentally by a lucky fool who blunders into a saltwater pool while fleeing the orgy of death chasing him, and is later adapted as a defensive measure against Henders creatures.
 * The main weakness of vampires in Peter Watts's Blindsight-verse is geometry. If right angles take up too much of their visual field, they have massive, frequently fatal seizures. Right angles are very rare in nature, but once humanity developed architecture the vampires went extinct until later humans reconstructed them and developed "anti-Euclidean" drugs to counter the special vampire weakness (and keep the vampires dependent).
 * In the Simon's Quest volume of the Worlds of Power series, Dracula's vengeful spirit can be driven off by bad jokes.
 * In Fred Saberhagen's Book of Swords and Books of Lost Swords series, Shieldbreaker, the Sword of Force, can defeat any weapon, and as such is the only thing that can defeat, even destroy, one of the other Swords, but is powerless against an unarmed man.
 * In The Wheel of Time, channelers are people and therefore are vulnerable to all the things that squishy humans are (though they can do things to help offset that). However, they are particularly vulnerable to Forkroot tea. In normal humans, it's harmless, if at most a mild sedative. In channelers it cuts off their ability to use their magic and knocks them out.
 * In Nick Perumov's novel Diamond Sword Wooden Sword, magic-users are vulnerable to the herb swamp crower. Its smoke makes everybody cough, but magic-users also temporarily lose their powers.
 * In Bystander Lucretcia won the Superpower Lottery. But, she has two big weaknesses. First, she is weak against hot weather. A warm summer day means she can't leave the air-conditioned car, or she'll blister instantly. Two, she sucks at using her powers. Especially fighting. Being as strong as Superman isn't much use when you can't HIT the opponent!
 * The kids in the Goosebumps book How To Kill A Monster have to figure out exactly how to do that. Falling three stories doesn't stop him nor does poisoning a pie. Luckily, there's a Deus Ex Machina way out.
 * Iron against the chaos mages in the Saga of Recluce. Even the strongest bolt of chaos fire can be stopped cold by a thin sheet of iron, and the more powerful a chaos mage is the more they're hurt by iron, to the point that what for anyone else would be Only a Flesh Wound will be a One-Hit Kill for an experienced chaos mage.
 * Bram Stoker's LiteratureDracula averts most of the popular traditional weaknesses; for example, he can't be killed by most conventional means, and can use his shapeshifting powers during dawn, noon, and dusk. However, he does have unique weaknesses; he can only cross running water during high or low tide (this amounts to 12 hours and 25 minutes per day), needs to keep a small amount of Transylvanian soil in his home, and needs to be invited inside before he can enter a building (considering this is Victorian era England and he is a noble, this is pretty much a non-matter).
 * Mercedes Lackey has fun playing with the iron weakness of fae; in her SERRAted Edge book series, the good elves not only use their skills as race car mechanics to work up a tolerance to iron, but also gladly use the metal to shield themselves from enemy elf attacks. It's also noted that elf magic goes haywire in the presence of iron. In the same series, however, she plays the Trope straight in that her elves have a powerful vulnerability to caffeine.
 * The Hunter from the Coldfire Trilogy is one of the most powerful beings in the series, but also fatally flawed in his nature. As part of his Deal With the Devil to stave off death, the Hunter surrendered his power over life, creation, and light. He can no longer use healing magic without dying, sunlight burns him horribly, and he is completely unable to manipulate ordinary fire. A villain in the first book took advantage of these weaknesses by luring him into a cave filled with crystal and used a mirror to reflect what little sunlight there was back at him, with the light magnified by the crystal. Then he was rendered helpless by being placed in an ordinary bonfire.
 * Animorphs has one book where the group finds out the Yeerks' Bizarre Alien Biology allows both them and the hosts to treat instant maple oatmeal as an addictive drug on par with heroin. While they plan on dumping a bunch of Quaker Oats' finest into the pool the Yeerks use to rejuvenate, they don't end up using it as a weapon because it plays merry hell on the hosts as well.
 * Captain Underpants loses his powers when he's subjected to spray starch.
 * In the Codex Alera, all of the various crafters' fury-granted Elemental Powers can be countered by their opposing element (i.e. dripping water on a firecrafter prevents use of fire furies, putting a woodcrafter in a metal cage nullifies wood furies, etc). Windcrafters have greater difficulty using their wind furies closer to earth, and being covered or surrounded by earth renders their furies impotent. However, they also have another weakness: salt, when it comes into contact with their furies, causes them great pain and disrupts them. As a result, anyone expecting to fight a windcrafter carries bags of salt with them to disrupt their Bullet Time, flight, and other powers. Salt-tipped arrows are a specialist weapon against hostile wind furies, and a salt-tipped arrow is  in Cursor's Fury by
 * In The Dresden Files all illusion has the problem that anyone capable of using the Sight can simply activate it and no matter how skilled the illusionist, they'll be able to see what's really going on. While most people avoid using the Sight due to the potential for seeing disturbing, unforgettable things with it, the ability for the most marginally skilled caster to totally counteract any illusion means that the Council doesn't consider it an especially useful discipline.
 * The Nazgul from The Lord of the Rings are vulnerable to sunlight and fire, and will not cross running water if they can at all avoid it. The first two are actually a Logical Weakness- as creatures of darkness and cold, it makes perfect sense that they wouldn't like light and heat- but Tolkien never explains (either in the books themselves or Word of God) why they feared water.
 * In the first book of Anne McCaffrey's Tower and The Hive series, The Rowan, Prime-level Talents could not travel off-planet, due to Travel Sickness - a severe form of vertigo. They later found out that this wasn't the case, but the older Primes consider it a phobia, rather than a medical condition.
 * All types of the fae in The Name of the Wind are susceptible to iron.
 * A secondary canon Star Trek novel (World Without End) describes Vulcans as being extremely vulnerable to cold, sufficient exposure to Earth's winters can kill them much faster than the exposure can kill a human. When staying on Earth briefly with his mother's family as a boy, Spock has to be completely bundled up whenever he is walking outside in the snow.

Live Action TV

 * Supernatural has ghosts who don't like salt.
 * "Truth in Television", or as close as you can get: A book on ghosts states that they actually can't stand salt. If you sprinkle some on your doorstep, they can't get in your house. It's supposed to be pure.
 * The Fair Folk are also weak against salt, sugar, or any granular substance. If some is spilled, they have to stop and count each piece. After losing a fight against one, Sam simply says "Why didn't I do this earlier?" and opens the capsule of salt he had on him.
 * For some reason the Leviathans
 * Doctor Who is renowned for ending its episodes either by Reversing The Polarity or exploiting the latest Monster of the Week's Weaksause Weakness. The most famous example is the Cybermen and their allergy to gold, which underwent a Power Creep, Power Seep, slowly going from "gold dust can gum up the works" to "touch gold, die screaming." It eventually lead to Silver Nemesis and the hilarious scene of Cybermen being stopped by gold coins and a slingshot. At the time a popular joke was that in their next appearance, just saying the word "gold" to one would kill it. This was quietly ignored in more recent episodes, since those Cybermen came from an Alternate History (though a Continuity Nod was made in a tie-in website which stated that said Alternate History Cybermen did initially have an "allergy" to gold, but it was eliminated by R&D). Mind you, no one has actually tried using gold on them yet...
 * "Image of the Fendahl" had the monsters defeated by rock salt.
 * Daleks are famed for their inability to climb stairs, though this was never established in the show. However, they could be blinded by obscuring their rather obvious eyestalks, or incapacitated by pushing them over. In their very earliest appearance they could only operate by absorbing static electricity, preventing them from leaving their city. This was later ignored, even in Genesis of the Daleks, which was set earlier. Over time, they became far more credible foes. They were actually shown climbing stairs in 1988's "Remembrance of the Daleks" (much to the Doctor's horror). In the new series, they can not only hover but swoop around like crazy ("EL-EV-ATE!!"), remove foreign substances from their eyestalk lens (much to Wilfred's chagrin), and incinerate humans on touch. Their main weakness now seems to be stupidity, given that the Doctor convinced them a Jammie Dodger was a TARDIS self-destruct device.
 * The Slitheen, due to their bodies consisting mostly of calcium, messily explode if acetic acid comes into contact with their skin, no matter how little. Cue the squirt guns filled with vinegar.
 * "The Fires Of Pompeii" has the Doctor fighting seven-foot rock beasts with a water pistol... and winning. Well, irritating them into backing off, not killing them.
 * The Sensorites from the classic-era first season. Afraid of darkness and loud noises. They panicked if you turned out the lights (we're not talking pitch-black darkness, either - half-lit darkness a person with modest night vision could navigate was enough) and could occasionally be cowed into submission by raising your voice.
 * "Blink" has creatures that can, when no one's looking, move faster than Jack Harkness confronted with a twelve-step program. When seen, however, they can't move. The episode plays this up for Nightmare Fuel, as you have to blink sometime ... On the other hand, their biggest weakness is
 * Apparently, a video recording of an Angel is an Angel in itself. The problem is, if you keep staring at it, it'll eventually download into your brain.
 * When an episode of Extras featured the filming of a mock Doctor Who episode, this very trend was parodied with a giant slug who was vulnerable to table salt--which he conveniently kept on his desk, just within reach of the Doctor. It's a reference to Colin Baker's first serial, The Twin Dilemma, where the Doctor really does fight a giant slug. In the novelisation, the Doctor briefly wonders where he could find a lot of salt, before dismissing the idea.
 * The Doctor has a Weaksauce Weakness of his own: aspirin.
 * The Doctor's sonic screwdriver "doesn't do wood" (Hee hee hee!) in that it can't help much against wooden latches and other such things.
 * It also doesn't do deadlocks, and can be deactivated by some hairdriers.
 * Sylar of Heroes could be reduced to a writhing, quivering lump with the use of a tuning fork after acquiring Dale's super hearing (though Dale was the same way). This no longer affected him after
 * Similarly, Elle possesses powerful electrical powers, but because of them can be incapacitated by a bucket of water, which shorts the circuit and fries her with her own powers if she tries to use them.
 * In Smallville, Aquaman's guest appearance explained that he needed to be constantly wet or otherwise have a glass of water or he loses his immense strength and begins to wither. Considering he has had plenty of his own superpowered problems, this is especially glaring.
 * In the show, Kryptonite is so common that Clark would almost be better off powerless. Especially problematic in the earlier years when his "monsters of the week" got their powers FROM kryptonite.
 * This (unbelievably large amount of Kryptonite on Earth) even made Ultraman flee his own reality because everyone had it and wouldn't hesitate to use it against him.
 * The classic Star Trek episode "Day of the Dove" features an Energy Being which feeds on negative emotions, and so causes total chaos on the Enterprise by provoking conflict in order to feed on it. Kirk eventually figures out that the alien can be driven off by peace.
 * In an episode of Star Trek the Next Generation, the crew deals with a hostile silicon based lifeform that draws its energy from light. They subdue it by turning the ship's interior lighting off.
 * In another episode the Captain finds an ancient Vulcan artifact believed to be some kind of superweapon. By that time he has realised its critical weakness--it can only kill people who have violent thoughts. Remaining calm renders it ineffective--even Worf is able to counter it using this method.
 * On All That, the character Superdude... is lactose-intolerant. Even throwing milk on him will send him to the ground, disabled. So of course, the bulk of his rogues' gallery is dairy-related: Butter Boy, Yo-Girl, Cow-Boy, the Dairy Godfather, & his Arch Nemesis Milkman.
 * In the '80s series V, aliens are vulnerable to certain inoffensive bacteria that live in human digestive tract.
 * The alien "Gua" in First Wave turn out to be badly affected by salt. It affects them roughly like heroin affects humans. One episode featured renegade Gua hiding out in a derelict building snorting packets of McDonald's salt. Of course, this is the same series where the hero fought the alien invasion using the lost diaries of Nostradamus, so...
 * Technically, we never see an actual Gua. They're husks - cloned human/Gua hybrids. it's entirely possible that actual Gua are immune to salt but happen to be crappy genetic engineers.
 * Did we mention that Nostradamus was actually ?
 * Sportacus, the superhero of Lazy Town becomes helpless if he eats things with sugar, like candy. However it may be that he's actually weak to chemicals added to sugar, as he can eat (and in fact gets stronger) from eating fruits, which contain natural sugars.
 * Also, candy is made from refined sugar which is simple glucose molecules that the human body metabolises, and thus runs out of, much faster than more complex fructose. This is a real problem for people with hypoglycemia.
 * Turned on its head by The Gentlemen who die instantly upon hearing a human scream. Because of this they steal everyone's voice, making themselves essentially invincible and all the creepier - they're cutting your heart out and you can't scream!
 * "The enemy of all magic" for the Wizards of Waverly Place is...wait for it...plastic! The Villain of the Week even manages to take over WizTech by filling the place with plastic balls. Considering how ubiquitous the stuff is in the mortal world, it's a wonder magic works at all. In later seasons, all spells can work through phones. Explain that.
 * A villain of the week on Misfits turns out to be allergic to peanuts, which gets cranked up to Mundane Made Awesome levels and treated as a Kryptonite Factor in the confrontation.
 * In Kamen Rider Double, the Utopia Dopant draws upon peoples' positive emotions, granting him incredible power. Inanimate objects, however, have no emotions to drain, meaning that the series' Big Bad gets manhandled by the same cute and Toyetic Robot Buddies that have been hanging around since Episode 1. In fact, one of the show's copious Crowning Moments of Awesome is protagonist Shotaro blocking Utopia's powers with nothing more than his dead mentor's Cool Hat.

Parlor Games

 * In Rock-Paper-Scissors, Rock's ultimate weakness is Paper (which covers Rock). The other two (Rock breaks Scissors and Scissors cut Paper) at least make sense.
 * This was mocked in an episode of Corner Gas; Davis chooses rock, while Karen chooses paper. Davis declares he won. When Karen says that paper beats rock, Davis counters with this: if you cover a rock with paper, it's still a rock - you can break a window with it.

Tabletop Games

 * A demilich from Dungeons and Dragons has gained such power in magic that it barely has a physical body anymore, only a portion, usually the hand or head, loaded with tiny gems which contain bits of their old body and act as anchors for their soul. They can absorb anything's soul by simply touching it, by definition have mastered lots of nasty spells, and are totally immune to all magic except heavy-duty holy magic. The one exception? A simple little 2nd level spell called Shatter, that destroys crystalline objects. Whoops.
 * Not as good as it sounds: At the Demilich scale of power, Shatter deals very little damage. Besides, demiliches are both very powerful spellcasters and extremely intelligent, so it's very likely that it'll just whip up a spell that offers protection from sonic damage.
 * Persistent Spell and Globe of Immunity (both easily learnable by anyone capable of becoming a demilich) renders this tactic completely impossible. It renders the caster completely immune to Shatter (along with any 4th rank or lower spell) for 24 hours per casting. Any caster is going to have numerous methods of defending against Dispel, so removing this spell might end up being more difficult than just directly killing him.
 * In Heavy Gear the advanced Black Mamba Gear - one of the more powerful designs in either of the two superpowers' armies - had exceptionally weak rear armour. The result is that Black Mambas could be (and routinely were in gameplay) easily defeated by lightweight Cheetah scout Gears. While the fluff text initially ingored this, the game's designers eventually acknowledged and lampshaded this weakness by having Mamba pilots clamouring for a solution to the "glassback" problem.
 * Most of the monsters in Lucha Libre Hero take extra damage from lucha combat maneuvers. And since the PCs are by default technico luchadors, there's a lot of these showing up in the fight scenes. But then, the sourcebook was inspired by Mexican lucha films, and "every problem can be solved with a good wrestling hold" was standard in those films.
 * In GURPS the disadvantage Supersensitive makes having any other sort of sentient creature with 20 meters a serious weakness. With Combat Paralysis your greatest weakness is being put in any sort of danger. Naturally such disadvantages are not recommended for Player Characters.
 * D 20 Modern has a table of random weaknesses... including some really stupid ones, such as: Clowns, the number 8, math, and books written by willam blake.
 * In the The Dresden Files RPG, all creatures who take some sort of supernatural toughness, regeneration, or physical immunity must take something called "The Catch", which, when used against them, will take out their ability to shrug off damage. The more common/easily accessible the ability to fulfil "The Catch" (so, something everyone knows about and can get easily), the more points you can get back. So, Catches like "Swords Of The Cross", "Wizards Born Under Special Circumstances", "Soulfire", and "Nuclear Detonations" don't really offset the power, while more common and known substances (like iron vs Fey, holy items vs Black Court Vampires, or physically attacking magically immune creatures with a brick loaded sock) will give you more points to potentially work with.
 * In Deadlands, there are some creatures and villains who are immune to anything except one weakness. For example, a Hangin' Judge is vulnerable to a weapon held by a legitimate lawman on duty, a Tummy Twister to hot chili peppers, and Jasper Stone to suicide.
 * That last one is technically correct, but it's so much more. The conditions are actually "Stone can only be killed by a gun fired by his own stone-cold hands", so suicide counts... but so would redirecting his shot before it hit it's target.
 * Changeling: The Lost has the concept of "frailties", little weaknesses that certain fae (and overly-powerful changelings) are prey to. Some of them are the classic faerie weaknesses, others can be as odd as "must drink alcohol instead of water" or "cannot cross lines of ants". The only universal weakness is iron, which isn't as dangerous as you think because pure iron is rare... and steel does nothing. It should also be noted that these weaknesses differ from subject to subject; the fiction for one book has a Genre Savvy mortal invoking every bane she knows from the old tales in an attempt to scare off one of the Gentry. None of them work.

In fact, the good elves have noticed that iron makes their magic go haywire in extremely predictable and repeatable ways, so they have incorporated it into their defenses and can use it to, for example, negate their enemies' magic while delivering their own with deadly accuracy.
 * Rifts has a little fun with the concept of fae weaknesses. Among the ways to protect yourself from Faerie Folk is to turn your clothes inside-out or backwards when traveling through their territory, or by tying colorful ribbons all over you and your gear. But this is less a matter of them being unable to approach you as it is them being too busy laughing to trouble you.
 * It's possible to give a character in Champions such a weakness via the Susceptibility Disadvantage. Water, for example, could be worth quite a few points depending on how many dice the character takes from it since it's one of the most common substances in practically any game world. Of course, this would make it impossible for your character to do such simple things as bathe or shower, and any kid armed with a Super-Soaker and/or a bucket of water balloons would become a credible threat.

Video Games
"Hooktail: Bleck! That awful sound! It... sounds like a ! How did you know?"
 * Razputin in Psychonauts cannot go into deep water because of a family curse (or just a bad case of hydrophobia).
 * It's a curse, and one that actively tries to kill him. Any time he goes near deep water, a hand made of water tries to drag Raz in and drown him.
 * The 'Mega Man series has plenty of bosses who had a weakness to unlikely-looking weapons and questionable moves.
 * The final boss of Mega Man 2 can only be damaged with the most useless and most difficult-to-hit-with weapon, Bubble Lead.
 * The final form of Wily in Mega Man 3 can be one-shotted with a proper application of Top Spin, a glitchy and hard to aim attack that often damaged you and would drain the entire bar if mistimed. (Thankfully, Search Snakes also work on it--which has much the same movement pattern as the aforementioned Bubble Lead and would be this game's hardest-to-hit-with weapon if not for the Top Spin.)
 * In Mega Man X 1 and 2, the final boss forms of Sigma were weak against the Rolling Shield (a hard to aim attack that generally did less damage than a charged shot) and the Strike Chain (a pathetically short ranged attack).
 * Wave Man of Mega Man 5 was essentially vulnerable to being kicked.
 * This comes up in the series so often that the Genre Savvy veteran of the series will, upon reaching the final boss, immediately switch to the hardest-to-use weapon to try fighting Wily. The cases where this isn't strictly true are
 * ROM Hack Rockman No Constancy makes Za Warudo/The World (which isn't even offensive) a One-Hit Kill (at least on Normal mode) towards Clash/Crash Man.
 * Don't even get us into how this applies to multiple-typed Pokémon.
 * Poor Shedinja. Its ability, Wonder Guard, is great (invulnerable to all direct damage moves except for the types it's weak against), but it only has one hitpoint, and its type (Bug/Ghost) gives it five weaknesses--including types and common moves that only an idiot would build a team without. That means it's only good against AI opponents that you know don't have those type moves (or any of the environment moves that would defeat it as well). Moreover, while it's invulnerable to direct damage moves, status ailments could affect it normally. Shedinja could simply be confused, and it would effectively commit suicide. Good luck leveling the poor guy without Exp Share.
 * Inversely, Shedinja is an extremely viable option in the Legendary/Uber arena, in that most of the commonly used Legendary Pokemon have no moves that can penetrate Wonder Guard. For example, the near-almighty Kyogre will be generated most of the time with no powers that can hit Shedinja, letting the tiny bug cut him to death. If you can take out the one or two (at most) Pokemon that could beat Shedinja, you've practically assured yourself a victory.
 * There's also Paras and Parasect, who in the first generation had three Super Effective weaknesses (Parasect is also incredibly slow). One of their new abilities in the fourth generation gives Parasect what is essentially a five fold weakness to Fire. Parasect also gets a 100% accuracy sleep move, which is potentially the most powerful status-inducing move in the game, so the Weaksauce Weakness was likely added to keep it from being a Game Breaker.
 * The Electric type is half-composed of cute little rodents (and a grinning sphere, too, but those are actually dangerous). You'll wind up with one-foot-tall squirrels and mice taking down Gyarados--a 21 foot long sea monster known for destroying entire towns in fits of rage--in one hit.
 * Several moves and other things introduced in the fourth generation of the games can cause examples of this trope. One of the most hilarious: a Grass-type move called Grass Knot that is said to work by tripping the opponent, and does more damage the heavier the opponent is. The result of this is that the heaviest Pokemon in existence, the Ground-type Groudon, can often be tripped to death in one hit by something as small as a Pichu.
 * Dragons are weak to Ice-type moves. This means that pseudo-legendaries like Salamence and Garchomp can be taken out in one hit by an Ice Beam from a Cloyster.
 * Somewhat in keeping with the game's theme, the Big Bad of Spore,, is weak against... Life! They can only survive on barren planets; creating a life-sustaining world literally kills them (although their spaceships can still bomb you from orbit).
 * Laharl in Disgaea, being a young demon who makes a big deal out of being evil, is violently allergic to women with sexy bodies and expressions of optimism or hope. In one battle he has to fight a bunch of half-naked succubi and nekomata with his stats halved; another time Flonne nearly kills him by yelling "eternal love!" (her favourite words).
 * This appears to be largely psychological, however. Laharl learns to accept by the end of the game, and while he makes a few comments about not wanting Jennifer's body near him, her presence has no effect on his stats. In Disgaea Infinite you can even use Mind Control to make him love sexy bodies, and glomp Jennifer.
 * The fact that the Prinnies explode when thrown is an unfortunate weakness, as well. It doesn't matter how high the level and/or stats of a Prinny is, a simple toss is all it takes to do it in. Unless it's one of those Prinnies...
 * In the Prinny games, said weakness can be exploited by a Prinny against some particular enemy Prinnies.
 * In Elite Beat Agents, an alien species known as the "Rhombulans" come to Earth and ban music because they're scared of it. Then the agents come and get everybody in the world to dance to Hoobastank and the Rolling Stones.
 * Sonic in the Sonic the Hedgehog franchise is extremely weak to water. Not only can he not swim, he also moves at an extremely slow pace when under. In the anime Sonic X he can't even move while underwater, and he can't move while on ice. There was an entire episode of Sonic Underground and Sonic X devoted to Sonic's aquaphobia. Also, in Mario and Sonic At The Olympic Games Sonic wears a life vest whenever he participates in a swimming event.
 * The final boss of Final Fantasy Tactics,, is incredibly weak to  . The AI even actively hones in on characters using it  . However, even a single Chemist is enough to counter these effects, and you can merely have the rest of the party wail on the final boss without it even bothering them for an easy victory.
 * Two of the three final bosses of the MOTHER series are established as ridiculously powerful, perhaps even immortal, up until the final fight.
 * In Baldur's Gate II, the extremely powerful liches rely entirely on magic in combat. There is a relatively low-level spell that allows you to polymorph into a 100% magic-immune and thus undamageable-by-liches creature: The Terrifying Mustard Jelly. Game Breaker ensues.
 * Also, all healing spells have reverse effects on undeads. The mid-level spell that heals someone back to max HP? It reduces any undead to one HP. Including an epic dracolich.
 * Taken even further with Bonus Boss Kangaxx. While he is definitely one of, if not the strongest enemy in the game, his death resistance is piss poor. There are so many ways of taking advantage of these, along with Good Bad Bugs, that someone wrote the song parody "Fifty Ways To Kill Your Kangaxx." ("Use Protect Against Undead, Fred.")
 * Cole from In Famous has the standard "electric super" Weaksauce Weakness of water... but also has one in chain-link fences. The metallic mesh absorbs his shots and dissipates them harmlessly. He has to go around to shoot whatever is on the other side -- since every last chain link fence in the game is capped with razor wire and can't be climbed. Penny Arcade didn't let this go without comment. It's even Lampshaded in the sequel -- you can now climb over chain link fences, and there's a trophy for doing so for the first time, celebrating this amazing achievement.
 * He has another weakness: areas without flowing electricity. If there isn't an active power grid where he is, he suffers from severely blurred vision and is said in dialog to be generally impaired, though this doesn't really show in gameplay.
 * In Prototype, Alex Mercer and the Infected have a Weaksauce Weakness in water. Their biomass is too dense to float. Alex and Hunters will just jump back out of any body of water they fall into after a brief pause. The Infected not so much. However, it takes place on Manhattan Island, so besides the surrounding water that makes it an island, there's not a lot of water to use. Makes the quarantine easier to keep, though.
 * Using Provoke on Defender X in Final Fantasy X will force him to use an attack that halves the target's current HP for the remainder of the fight (unless the Provoker switches out of battle). Therefore, the fight becomes a Foregone Victory.
 * Many other bosses have some exploitable weakness (some more obscure than others), making a "level one" run easier than you might expect.
 * Okami monsters can have some pretty weaksauce weaknesses:
 * The "Bloom" technique, that causes flowers to sprout from trees, will also open bud-based enemies and reveal their weak point.
 * Umbrella-wielding and flying enemies are weak to "Galestorm" which most of the time isn't any more powerful than a moderate breeze.
 * The Tengu can be calmed down from going berzerk by causing it to rain.
 * The Big Bad is weak to, but then again,.
 * The Bonus Bosses of Mana Khemia Alchemists of Al Revis are very powerful, to say the least. However, they all share a common monster trait that renders them vulnerable to a certain character's normal physical attack. Said character is one of the highest physical attackers of the game (plus, he also has a skill that increases his attack power even more), and abusing the weakness will quickly increase the Limit Break meter, allowing faster access to the uber-powerful Finishing Bursts. This is a saving grace, however, since one Boss Battle has you fighting three Bonus Bosses at once.
 * In Devil Survivor, the Nigh-Indestructible enemy Beldr is only harmed by Devil's Fuge . Makes up for it by being That One Boss of the game, but still a rather undignified weakness--but justified, due to the boss's background origin.
 * An odd case in Tales of Phantasia, which isn't a conventional weakness, but more of a developer’s oversight. The Bonus Boss of the Bonus Dungeon, Pluto, only has physical attacks, and one ridiculously long charging special attack, all of which have insane amounts of damage behind them, but must be used at close range. The first skill the main character ever learns is a long range, one SP cost move called Demon Fang', which instantly pushes pluto back and flinches him. Hence, a Bonus Boss battle where the heroes stay on oneside and nuke the poor guy and the lead constantly pelts him with Demon Fangs, while the boss sits on the other side of the screen defenseless.
 * In Castlevania: Portrait of Ruin, there's an optional battle with the spirit of . A hero from past games, he's one of the most powerful vampire hunters ever to walk the Earth. So what's the best weapon to use on him? Why, cream pies, of course!
 * To elaborate a little: is weak against the Darkness element. One of the few sub-weapons you can get your hands on with this element is--for some reason--a cream pie. Which means the easiest way to beat him is to keep throwing pies in his face. Really.
 * It seems that human(ish) enemies in the Resident Evil series are more vulnerable to melee attacks than they are to heavy firepower and ordnance. Krauser from part 4 is weak against Leon's knife, and in part 5, the first two fights with Wesker can be considerably shortened by clobbering him with as many QTE combos as possible.
 * In Resident Evil 4, the Plagas that hatch out of the various Ganados are either Demonic Spiders or Goddamned Bats, depending on your opinion. However, once "popped", they can be killed instantly with a single flash grenade... yes, that's right, the otherwise useless blue grenade you've probably been selling off for upgrades and beefier guns.
 * In Diablo II, a Paladin using the skill Blessed Hammer (commonly known as Hammerdins) are capable of throwing dozens of high-damage hammers at a time, even into the highest difficulties. Their weakness? Walls. Since the hammers arc in a circular pattern, it can be extremely difficult to defeat certain monsters who are positioned in a difficult spot. There's a reason why the most effective equipment for a Hammerdin has an item that provides the Teleport spell: because there's quite a few mandatory sections of the game that are best served teleporting around, avoiding enemies, grabbing the one item you need, and getting the hell out of there.
 * Ormagodden from Brutal Legend was killed by being doused with mud.
 * Penny Arcade Adventures features a literal example: the special-attack weapon "Double-Mild Weaksauce" is such a wimpy hotsauce that it actually makes enemies wimpier and more vulnerable when you shoot it at them.
 * Although not a flaw of the units themselves, ground units in X-COM Apocalypse can only travel on roads and if the road square they are on is destroyed so are they. Especially galling with the Assault Tank which is pictured as having huge caterpillar treads but still can't go off-road.
 * In Final Fantasy games in general, Revive Kills Zombie, so even undead bosses can be easily killed as long as you have a Phoenix Down in your inventory.
 * Some Final Fantasy games, mostly the more recent ones, either makes Phoenix Down/Life spells have a very low hit rate for undead bosses or are completely immune to being killed instantly from these techniques. Doesn't exactly stop players from spamming healing spells or potions instead, which are just as effective!
 * In The Secret of Monkey Island, Big Bad Le Chuck is destroyed by.
 * In Nelly Cootalot, there's El Mono, who guards the gates to the mine, with some pretty powerful (as Adventure Game standards go) magic. So what is an ordinary Pirate Girl to do? After doing a few more errands, the answer will come in the form...of an orange.
 * Meta-Knight isn't afraid to get bloody in battle...but he is afraid of losing his mask. Every battle with him ends with his mask coming off, revealing that he's every bit as cute as the rest of the inhabitants of Pop Star. He immediately wraps himself in his cape and leaves.
 * Scarabs are somewhat easily beaten in Halo wars, stick an infantry unit too close for it to hit and send your army after it while it's stuck. They tend to die quick unless they have engineers.
 * While we're on the subject of Halo, in the first game, the Hunters were enemies who could easily ruin your day. The best way to kill them, other than a rocket, was a single Pistol round to the unarmored area in their back. That's right, just one Pistol bullet. Bungie nerfed this ability of the pistol in the games later in the series.
 * This is especially jarring since the Hunters are supposed to be not a single being but colonies of hundreds of small worms with a Hive Mind. So shooting a few with a bullet should only feel like a pinprick to the overall being. Granted, it could be a hollow-point round that bounces around in that armor, but that seems unlikely.
 * Kanbari in Shin Megami Tensei: Strange Journey is weak to physical attacks, and each hit against him generally results in a cooperative attack with your allies. To be fair, he's the god of the toilet, so players are right not to expect much.
 * Be careful, however - Kanbari does know Tetrakarn (which reflects physical attacks).
 * The most likely candidate for the Big Bad of Blaz Blue, Terumi, is a Complete Monster of the highest order and story-wise one of the most powerful beings alive...and he is allergic to cats. Horribly allergic. So allergic that  It's hinted to be canon too; in one scene he mentions that he hates the smell of cat. It's possible that Relius Clover, a Jerkass Complete Monster in his own right, added those allergies when he created Terumi's current body as a twisted joke.
 * Kratos from Tales of Symphonia's weakness is tomatoes.
 * Every playable character in the game has a least favorite food in the same way - Kratos' is just the only one that became memetic, probably because he's so stoic as to become The Comically Serious. It's not like they can ever get used against him in battle or anything.
 * Captain Novolin is weak against junk food. It makes him sick when he gets near it.
 * Hooktail, the boss of Chapter 1 in Paper Mario the Thousand Year Door, has a weakness to things that start with "cr" and end with "icket".


 * In Sim City 4, most buildings and infrastructure will crumble to pieces if you move the ground near them.
 * Master Belch from Earthbound.
 * The Pork Trooper in MOTHER 3 has a weakness to
 * Touhou: In Immaterial and Missing Power, Patchouli tells Youmu that she ought to be weak to fire since she's (half) an undead. Youmu replies that it doesn't apply to ghosts. In the end her human half turns out to be weak fire, but then again who isn't?.
 * In her scenario, Patchouli ends every fight by listing her opponents weaknesses that often turn out to be weaksauce (although the validity or application are doubtful):
 * Reimu: Wasabi.
 * Marisa: Eel.
 * Sakuya: Asian ginseng, bitter melons.
 * Alice: Chili peppers.
 * Youmu: Bitter melons.
 * Remilia: Lots of weaknesses....
 * Yuyuko: Fire.
 * Yukari: Dried plums.
 * Suika: Fried beans.
 * Youkai are said to be able to regenerate physical damage very fast, but are weak to faith.
 * Finally Oni (which in this verse includes devils and vampires) are believed to be vulnerable to boiled beans, but apparently this is only because humans think so.
 * In the SNES Wizard of Oz game, the Tin Woodman is normally useless, since he can't crouch or jump, but his attack is apparently the only one that can hit the Wicked Witch.
 * In The Legend of Zelda a Link To The Past, Mothula is generally considered by far the most difficult fight in the game, since it's meant to be killed with the fire wand but most players don't have enough fuel to get the job done. However, you can deal massive damage if unleash a bee on him... (It's worth noting that this is the only boss fight this tactic will work for, so perhaps the game designers realised how disproportionately difficult it was normally).
 * Minecraft's final boss, the enderdragon, is extremely difficult to defeat with a sword, and arrows take a long time to bring it down. However, they can be damaged with snowballs, which usually just knock mobs back without hurting them. Since snowballs can be stockpiled easily in a snow biome, and can be thrown much faster than arrows can be shot, they're probably the easiest way of winning the fight, and most people would never think to use them since they're harmless when used against 95% of the other mobs.
 * World of Warcraft is rife with such weaknesses to make otherwise impossible encounters winnable or just for amusement value. One great example is a quest where you have to get an artifact to defeat a pack of imps. The effect of this awesome weapon? It creates beautiful rainbows... cue sound of heads exploding.
 * Castlevania II Simons Quest features the easiest fight against Dracula in the entire series. There are two weapons  which cause Dracula to completely freeze in place. All Simon has to do is repeatedly spam those weapons, and he'll win before Dracula can even move.
 * In Super Robot Wars Z 2: Saisei-Hen, The DAMON are affected by Basara's singing. They even take damage, making Basara a viable choice for fighting against the DAMON.

Web Comics

 * Cheshire Crossing (by the creators of Casey and Andy) delves into the weakness from the The Wizard of Oz: The Wicked Witch of the West explains that all witches are vulnerable to water (while in Oz, at least)--she was keeping the water on hand should Glinda the Good Witch launch a surprise attack. (In a later scene, the bucket is labeled "In case of Glinda".) She just never expected her enemy to bully a little girl into doing the deed.
 * Another spoof of The Wizard of Oz comes from Magicians & Munchkins; the Wicked Witch Of The West simply took this disadvantage to get a few additional levels in magic.
 * Toothgnip the goat in Goats gets his Kavorka Man powers from "The Panties of Potency". This had nothing to do with the artist having trouble drawing Toothgnip standing on all fours, honest!
 * Parodied in this strip of Order of the Stick, where, since Haley always has her sandwiches without pickles, Crystal thinks they're toxic to her.
 * In one Bob the Angry Flower strip, Bob thinks that a superhero has the Weaksauce Weakness of bacon. He turns out to be totally wrong, but we never find out what the weakness actually is.
 * Another one has Bob running a hot peanuts stand, recognizing a customer and his friends as a band of supervillains, and instantly and correctly deducing that they are actually buying ammunition for an attack on Anaphylactic Man's fortress. (He sells it to them anyway.)
 * Yet another has Bob defeating an evil skeleton with the obscure knowledge that skeletons have a fatal weakness to raisins. Yeah, it's that kind of comic.
 * This episode of Dinosaur Comics claims to have been inspired by this trope. More specifically, it's about the dangers of peanut allergies, orange juice, and the water that takes up 70% of the earth's surface.
 * Tales of the Questor subverts this with the fey. General belief is that they are vulnerable to "Cold iron" but this proves to be false. Research into why the iron did not work reveals that the ancient documents that the information was obtained from were actually misprinted versions found in an ancient garbage dump and that the symbol for cold and the symbol for north are very similar. Turns out the weakness is not cold iron but "north seeking iron" (lodestone), they are vulnerable to strong magnetic fields. Unfortunately only the weakest fey have this vulnerability, the strong ones can shrug it off (though with immense pain).
 * Bob and George, Tomahawk Man is lethally allergic to Plant Shield, something Mega Man considers to be the crummiest power in the series. However, what really takes the cake is Ran Mark II, a monstrosity so intimidating it makes Bob virtually shit his pants. However, he is vulnerable to one of the most common substances in the Bob and George setting: Ran Mk I corpses. Bob, a demigod of fire, is flat fucking terrified of Pokémon.
 * In Goblins: Life Through Their Eyes, Klik, a sentient metallic being able to fly, morph into just about anything, and absorb genetic information from flesh-based life-forms, is corroded when coming into contact with blood.
 * In Sequential Art, the Denizens (little black shadow creatures) are dependent on their leader when they try to conquer the Earth. When he is killed, they just mill around the house, helping out or watching soap operas. And this leader can brandish a chainsaw, but just like the rest of them was small enough to be placed in a drinking glass and thrown out a window. Also,.
 * This trope and the classic superhero Twinkie advertisements are brilliantly parodied in this Super Stupor comic.
 * Sluggy Freelance
 * At one point, the bad guys have robotic water-coolers that short circuit on contact with water. Yeah, someone really didn't think that one through.
 * The Evil, a litter of kittens made invincible, bloodthirsty fiends by Satan still suffer the psychological limitations of being kittens: give them milk, balls of string, or some toy mice, and they'll be too distracted and contented to murder you.
 * The demons of the Dimension of Pain can't stand the smell of flowers. This means that they can't enter the sewers in the Dimension of Lame, that place being a real Sugar Bowl.
 * In A Girl and Her Fed, the agents with the Pocket President chip installed get incapacitating migraines when exposed to really bright light. It's why they all wear the Cool Shades.
 * Charby the Vampirate: "Classic" vampires have all the classic weaknesses of the vampires, while "elites" possess none of the weaknesses, save one... Obsessive Compulsive Disorder. If they come across a pile of identical objects (a pile of rice, beans, the beads from a woman's dress that had accidentally come apart), they have to count it, regardless of the circumstances. For classic vampires, this can cause them to count until the sun comes up, and they die. For elites, trying to use this on them just ends up pissing them off, since the sun has no effect on them.
 * And Elites can still go around that with mathematics: Charby is seen weighting both a small sample and the whole heap on pocket scales, and deducing the total number from the sample size.
 * Liz's beast-man of a boss in Dead Winter doesn't really know how to fight, yet is still able to take on Monday pretty effectively due to his sheer giganticness and indestructibility. Monday stabs him in the shoulder, kicks him in a certain area, etc. but never really fazes him; the heroes end up smashing him in the head with a metal pole attached to a fast-moving car, but this only stuns him temporarily. His weakness? Germs--the imaginary kind. He's such a hypochondriac that slapping him in the face with a dirty mop will give him a panic attack. He gets over his fear of zombie infection pretty quickly, though...
 * Axe Cop's weakness is being surprised. He melts. And his second weakness is cherry rainbow.

Web Games

 * Monkey and Secret Army 2 ends with the monkey becoming a superhero to battle the Giant Enemy Crab.

Web Original

 * In the Whateley Universe, The Fair Folk (and mutants who are turning into Fae) are vulnerable to cold iron. Wrought iron benches, cast iron skillets, and so on. But Fey is also vulnerable to synthetic fabrics which give her a burning rash. She could be incapacitated by rayon lingerie! (Or The Seventies.)
 * Phase subverts this trope by getting a fake weakness put on his powers testing results. Dark chocolate, administered orally. So now she can have enemies try to stop her by bringing her delicious desserts.
 * Apparently there is a reviewer that can be destroyed by edutainment games.
 * In the Star Wars fan film Pink Five Strikes Back, Rebel pilot Stacy realizes that since the walkers attacking Hoth only had forward-facing guns, the Rebels could've just shot at them from behind. While being chased by a scout walker in The Return of Pink Five, Stacy remembers this train of thought in the nick of time - and causes the walker to lose its balance and crash by running in between its legs.
 * In the Global Guardians PBEM Universe, plastic, a substance unknown to the Ancient Greeks, is completely opaque to the Mask Of Justice's vision powers. Thus, he can't even see through Saran Wrap (tm) while wearing his mask. (This weakness extends to other substances unknown to the Ancient Greek magicians, but plastic is the one that keeps coming up.)
 * Mongibello, a "geokinetic" who can control and move earth and stone, can be rendered powerless simply by picking him up, or otherwise prevent him from touching the ground.
 * Edds World: In one of the early Christmas specials Edd is saved form death when he finds the Grim Reaper's one weakness: Gravy.
 * In Yu-Gi-Oh the Abridged Series, Big Bad Marik can only Mind Rape and control people if they're named Steve, creating an army of Steves. He even gets a couple of the main characters to unknowingly sign a contract that changes their first name to Steve.
 * The Centaurians in The Pentagon War are cold-blooded. They automatically hibernate whenever it gets too chilly.
 * In Group of Weirdos, the Iron Knuckles are completely invincible, unless tag-teamed and attacked repeatedly by Link, the hero of time, and Ganondorf, a dark wizard with great power. Or you can just slash them a few times with a Deku Stick.
 * "Kitten Fight!" "No wait, I'm allergic to adoreableness!"

Western Animation
"The Tick: "And that's just it, Doc - my mind has always been my Achilles' heel!""
 * This trope appears as a pastiche in Bolt. The titular dog believes he has superpowers because he never leaves the set of a TV show. When he is accidentally shipped across the country his powers "mysteriously" vanish, and he blames the Styrofoam packing peanuts he was shipped with.
 * The titular character of Invader Zim is a member of a hyper-advanced, genetically engineered race of aliens for whom Humongous Mechas are a mundane occurrence and whose sole purpose seems to be conquering the entire universe. His main weakness? Water (possibly just polluted water) and meat.
 * Though, unlike the Signs aliens above, he managed to devise a solution with a few minutes of thought, after literally stumbling onto Earth. The Signs aliens had studied the Earth before attacking, and still managed to fail. (Which says something about the Signs aliens as Zim is otherwise a functional retard.)
 * Captain Planet, being a paragon of clean Earth, is weak against your usual forms of pollution (smog, toxic waste, etc.), as well as Hitler-level hatred, apparently. You might consider these not particularly weaksauce, but it suggests Gaia went seriously wrong in the design stage: the things he was created to fight against are the things that do him the most damage. It's like J'onn J'onnz deciding to be a firefighter or Alan Scott deciding to only fight evil loggers.
 * His evil counterpart Captain Pollution has an even lamer weakness: clean water. Yes, any remotely clean source of drinking water sprayed in his face will make him bow down and crawl helplessly. This seriously deters his ability to establish himself as a credible threat.
 * Namor the Sub-Mariner of Marvel Comics is similarly affected by pollution (though not by hate, which is good, since he seems to run on it), but that makes sense, as he's a water-breather. Because he's a Half-Human Hybrid, he's also subject to insanity and fits of rage if he stays submerged for more than two weeks. Or emerged for more than two weeks. So he needed to switch environment every week to stay sane. Until authors simply forgot the issue.
 * The only thing that prevents Brother Herman from taking over the world in Yin Yang Yo is the fact the he's allergic to panda fur. As long as Master Yo, the last panda on the planet, is around, failure will be his only option.
 * His brother Carl, The Evil Cockroach Wizard has been shown to be a very powerful villain capable of global domination himself, he has one glaring weakness: self-esteem. He's been defeated by insults and peer pressure, and his own low opinion of himself keeps him from going full-tilt against the heroes and his brother.
 * Stitch of Liloand Stitch is unable to swim due to his extremely high molecular density, making him vulnerable to any body of water large and deep enough for him to be unable to claw his way out of before he drowns. Other than that he is one of the most powerful creatures in his continuity. Funny enough, in one episode of the animated series, Lilo tried to take Stitch to the vet. He decided to hide from her, in the shower.
 * Ummmm, kinda hard to drown in a shower unless you modify the shower to help you drown. Water dosen't hurt him, he just can't swim and needs to breath...
 * Birdman from the old Hanna-Barbera cartoons had the powers of flight, energy beams that shot from his hands, enhanced strength, and a personal force field -- and drew his powers from the light of the sun. Fair enough, there are plenty of other solar-powered heroes out there (Superman, Cyclops (sometimes), Starfire). Unlike those heroes, however, Birdman apparently had no energy reserve; he became weak as a baby after being removed from sunlight for less than a minute. As it was implied that being out of the sun for an extended period of time ("extended" apparently being something like five minutes) was fatal to Birdman, it's a wonder he didn't spontaneously drop dead at night. No wonder he became a lawyer.
 * After he became a lawyer, he developed an entirely new Weaksauce Weakness; he's completely worthless if he loses the Birdman insignia that he keeps on his forehead.
 * In an episode of Ben 10, it turns out that the leader of the Galactic Enforcers (an alien superhero team, said leader an obvious parody of Superman) has a devastating weakness to chocolate, which Ben himself points out is a lame superweakness.
 * The members of the Sushi Pack are rendered powerless by any kind of heat, but even worse, they feel compelled to announce this every time a villain pulls out a heat lamp.
 * Word Girl isn't so much defeated by a cute little kitten, but rather easily distracted by one. She also compensates for her language abilities by showing a complete lack of competence in art, poetry, and dance.
 * Parodied in Futurama: "The human was impervious to our most powerful magnetic fields, yet in the end he succumbed to a harmless sharpened stick!"
 * "Who would have thought a small amount of liquid would ever splash on meeeee!?"
 * An episode of Martin Mystery had an alien fungus monster that had taken over a small town and replaced the inhabitants with clones. Both it and the clones could be killed with salt. As luck would have it, the small town just happened to be in northern Utah.
 * Mumm-Ra from Thundercats, with a weakness to his own reflection. The writers eventually realized this made Mumm-Ra too lame, so they had him get over it. The Thundercats had a harder time dealing with him after that. Even more so when he got an Infinity+1 Sword of his own.
 * When Buttercup wanted to become a better superhero in The Powerpuff Girls episode "Super Zeroes", she became Mange, a knockoff of Darker and Edgier comic book Anti Heroes -- Spawn in particular. However, when the time came for her and her sisters (both of whom also assumed their own "better superhero" identities) to go out and fight a monster destroying Townsville, Mange was the only one who stayed behind, saying it's too bright and that she only travels at night. Mange then spent the rest of the day sitting on the couch with Professor Utonium until night fell, arriving too late at the scene as the monster had already left (her sisters were also late for reasons of their own). The three girls spent the night under a tree. When the monster came back to face the girls again, Mange sits out the fight, preferring to stay under the tree's shade. This attitude led the monster to eventually call her "Little Miss Darkness who’s afraid of a little sun".
 * Of course, being kids in preschool, the girls have plenty of weaknesses of their own any other time--they have been shown to be deathly afraid of "cooties", cockroaches, and broccoli. Of course, the episodes these weaknesses show up in usually involve some sort of super-powered or evil version of it, so it's not always so silly...
 * There's Antidote X which was used in only one television episode (Slumbering With The Enemy, on the girls themselves) and in the movie (on Mojo Jojo).
 * In Gargoyles, the titular creatures turn into immobile statues during the day, which leaves them extremely vulnerable. They try to work around this in various ways (working a deal with humans in exchange for protection, magic spells, etc.)
 * This is actually a bit of a double-edged sword. Though vulnerable as stone statues, they are COMPLETELY healed of almost ANY wounds (even potentially fatal ones) when they return to flesh and blood. Hudson, being the most experienced of the main cast, uses this to his advantage, defeating the better armed and fitter Demona while protecting an injured Goliath by simply keeping her at bay until dawn. When the sun sets, Goliath is healed and they easilly dispatch her together.
 * Oberon's Children, like other portrayals of The Fair Folk, are all vulnerable to iron. Iron can disrupt their magic, actually hurt them, and imprison them. In his  first appearance, Puck is forced to obey Demona after being bound with iron chains. The Weird Sisters are also coerced into doing a favor in exchange for being released from an iron chain. Later, the Trickster God Coyote is trapped in the robot Coyote's latest body which was constructed with iron from a magical cauldron. Their ruler Oberon, while not immune to iron, is powerful enough to withstand being impaled by an iron harpoon though it does cause him to wither in appearance for a short time.
 * In Teenage Mutant Ninja Turtles: Fast Forward Sh'Okanabo's first attempt to infect Earth with his progeny is thwarted by...sunlight. Although this is handwaved as a particular, unexpected feature of Earth's, and Sh'Okanabo himself is not normally affected, dealing with his weakness is the thrust of his character arc throughout the remainder of the season.
 * In one episode of The BOTS Master, the Big Bad uses a special alloy to make his Mecha Mooks Nigh Invulnerable. The good guys think that they're totally screwed, until the inventor of the alloy tells them that the alloy can be dissolved by...citrus acid. In the end they use lemon juice to defeat the new Mecha Mooks.
 * In Kim Possible, Felix Renton's Cool Chair is one of the most advanced pieces of technology in the series. It can hover and has Combat Tentacles. But it can be hijacked by a wireless game controller.
 * Not exactly canon for Darkwing Duck's mythos, but when he retells his origins in "The Secret Origin of Darkwing Duck," he describes meeting another hero whose weakness is Coo-koo Cola. She winds up falling into a vat of the stuff at a factory and, well ... adds to the Disney series' death count.
 * There's also Comet Guy (Super Weight: 3), whose Achilles Heel is that every time he hears the sound of a bell, he starts dancing mindlessly until he hears a whistle. His intellect might also count, but frankly it probably can't even do 2+2.
 * The Fairly Odd Parents: All that fairy magic is neutralized when they are under a butterfly net.
 * There's also all the various "Da Rules" which prevent them from undoing some of the more disastrous wishes, but do nothing to stop them from getting into these situations to begin with. One thinks an "I wish that no wishes that will somehow prevent me from undoing those wishes can be cast" wish might save a lot of trouble.
 * The alien jellyfish in the Spongebob SquarePants episode, "Planet of the Jellyfish", dissolve into puddles of goop upon contact with mayonnaise.
 * Codename Kids Next Door: The Kids overcome Father's pyrokinesis by drenching him in ice cream.
 * Desiree from Danny Phantom. Her main weakness is that she has to grant every wish she hears, including wishes like "I wish you were defeated."
 * The Fright Knight is also stupidly vulnerable. If his sword gets sheathed in a pumpkin, he is instantly defeated. His worst nightmare is probably somebody using an ordinary pumpkin as a shield.
 * Although not a fatal weakness, The Tick's mind is... frequently ineffective, as well as being easily distracted by shiny objects. If it wasn't for more competent sidekicks and fellow superheroes assisting, he'd have serious troubles with any supervillain more intelligent than a grape. Like being mind-controlled by Mr. Mental.


 * Also if you can get rid of the feelers on his head (As The Terror was able to do with his Wish Machine) The Tick completely loses his equilibrium and can't even keep his balance.
 * Mighty Ray of Hero 108 has the ability to shoot lightning from his eyes. The drawback is that he has to eat a banana to do it...and he hates bananas.
 * Several characters from Cat Dog refer to this trope as "Porkfat", named after the weaksauce weakness of the in-universe movie character, Mean Bob.
 * Bureau of Alien Detectors: When making an unstoppable zombie army, it's a good idea to ensure that the one thing that will kill them doesn't exist naturally in the atmosphere.
 * Jimmy Two Shoes: According to Word of God, Lucius actually has some pretty terrifying powers, including Reality Warper abilities. The sole reason he doesn't use them is because his Pride would be wounded if he admitted he needed them. Without them, he becomes a rather Harmless Villain.
 * According to God the Devil And Bob, Satan can't stand Tony Orlando songs. This comes in handy the one time he actually tries to knock off the comedy routine and physically attack Bob.
 * Ben 10 Ultimate Alien features in one episode an otherwise-invulnerable plant monster that dissolves on contact with... peanuts. No explanation is given beyond "it's allergic".
 * The Imperium, White Martian expys in Justice League have an even greater weakness than the usual fire. Direct sunlight causes them to burn and evaporate near instantly. One would think they'd be moving along planet systems away from suns, but no.

Real Life

 * Life as we know it is remarkably fragile; too little or too much of any one thing can kill. In fact, except for (parts of) the surface of one small planet, there is no known place in the universe where an unprotected human could survive more than a few minutes.
 * There are lots of things that can kill. Humans have tried most of them.
 * Any human being, no matter their condition or how healthy they are, are at risk of Commotio Cordis (agitation of the heart). This requires being hit in the chest over the heart at the right point of a heartbeat. Only a few dozen cases are reported per year, but victims are almost guaranteed to die if it happens (survival rate is 35% ... if the victim is treated in three minutes). Even a gentle blow that doesn't bruise the skin can trigger commotio cordis--which means every time you get hit in the chest, you're playing Russian Roulette.
 * Allergies. Nuts, animals, shellfish, bananas...
 * Some people suffer from Aquagenic Urticaria (water allergy). That's right, there's people who were unfortunate enough to be born allergic to a substance they can't live without. Any moisture build up on their skin aggravates the condition, so they must carry umbrellas with them at all times, avoid heavy clothing/exercise to prevent sweating and prefer to remain indoors in well ventilated surroundings. For all their precautions, though, they still have to wash themselves with water regularly.
 * There's a lot of stuff that can incapacitate a human. Tickling is a lot of peoples' weaknesses and a lot of people have a sound that 'goes through them' like the sound of plastic folders being rubbed or nails on a blackboard. Since these are all individual traits, though, YMMV.
 * British sailors in the 19th century hated eating fish or any food from the ocean for that matter, preferring weevily biscuits and gruesome salt pork or beef to fresh fish. Sailors hate the sea, pilots hate the wind, and retailers hate customers--Weaksauce Weakness in its truest form.
 * The right pattern of flashing lights can cause nausea in just about any human, people with epilepsy simply have a more severe reaction.
 * This has since been weaponized
 * And now you can build your own.
 * Tropers: Little do some know it, but the wiki they created is eating their spare time. and if you do know, knowing doesn't help a bit.
 * Gastropods, especially slugs and snails, are composed mostly of water. So what defeats them? The anti-water: Salt.
 * Then how come most species of gastropods live in saltwater?
 * Water-based gastropods like sea-slugs have gills while land-based slugs and snails have lungs. Land-based snails have very thin skin and the salt attracts the water in their bodies so strongly that it literally erupts through the snail's skin. Imagine if human blood was highly magnetic and someone waved a powerful electromagnet in front of you. The sea-slugs survive the salt water because they have the weight and pressure of an ocean on them.
 * Giraffes can easily suffer fatal neck and head injuries just from falling over. Don't believe it? Just imagine the whiplash with a neck that long...
 * This is true of most large animals--the bigger you are, the worse falling over is for you. That's why, for example, elephants keep at least 3 legs on the ground when running (rearing up on their hind legs, as is sometimes seen in circuses, is not a natural behavior). Gravity is a bitch.
 * Most electronic devices can be damaged irreparably by brief contact with water.
 * It isn't the water that kills it. All electronics are only good up to a certain voltage or current. Go beyond the specification of a given part for either and it goes boom. Water simply provides a method of short circuiting the gadget, thus bringing the current over what the electronic likes, usually. If you dunked a cellphone (without the battery) in water and let it dry for a day or two, it could still operate. Wouldn't recommend you try it though.
 * In fact, the best way to clean your keyboard if it can take the abuse? Run it through the dishwasher.
 * When an electric device has become wet it can be dried quicker by first dunking it in another fluid (that may or may not be able to shortcircuit the electronics by conducting electricity itself) with a lower boiling point. This fluid will replace most of the water in the device and afterwards evaporate quicker, leaving the device dry and ready to use sooner.
 * Static electricity can do this as well if you touch electronic components directly while carrying a charge in your body. Your desktop can be murdered by your carpet.
 * The transport infrastructures of many countries (such as the UK) are vulnerable to ice and snow. That includes roads, rails, and airports.
 * Aircraft that employ stealth technologies can very easily lose their stealthiness to the most mundane of things.
 * The F-22 "Raptor" is one of the most advanced stealth fighters in the world. Yet the radar-absorbent coating can be easily damaged by water, significantly increasing its visibility to radar.
 * The F-117 Nighthawk, the world's first stealth fighter, had a radar-absorbent coating that would be ruined by just leaving fingerprints.
 * Irrational fears can be constituted as weaknesses. If you're lucky enough to catch one of those Maury episodes, you can see fears of mustard, butterflies, lettuce, and so on.
 * Some people with PTSD have triggers of the Nightmare Retardant variety that, out of context seem laughable to those who aren't triggered by them, but remind them in some way of their traumatic experience and can trigger anything from an uncomfortable sensation to a full-blown flashback of the event. To make things worse, people with this kind of trigger will sometimes experience belittlement if they dare to disclose it.
 * Going a night or two without sleep can severely weaken you, both physically and mentally.
 * Diabetics have sugar. Too much AND too little.
 * Albinos have sunlight.
 * How about fear of relationships when society as a whole tells you that you're worth nothing if you're single?
 * The RIAA came up with a brilliant new method for encrypting data on C Ds. It can be negated by drawing a circle on the CD with permanent marker.