Hero-Killer



""A little piece of advice: You see an Agent, you do what we do -- Run. You run your ass off.""

- Cypher, The Matrix.

A villain who is so terrifyingly powerful that he strikes fear into the hearts of the characters. Whenever he shows up, they know of his abilities and that they are in true danger of being Killed Off for Real, and most of the time the best they can do is run as fast as they can.

A Subtrope of The Dreaded, with the proviso that Hero Killers like to get their hands dirty. When a Hero Killer tracks down a main character, a No-Holds-Barred Beatdown or a Curb Stomp Battle will ensue, with possibly fatal results. If the hero decides that he's Tired of Running, it provides evidence that he has taken a level in badass. If the hero wins the fight, or at least gives the Hero Killer a run for his money, it may be a Moment of Awesome.

Such a character nearly always causes The Worf Effect, to demonstrate exactly how much he outclasses the heroes. He invokes Anyone Can Die by his mere presence, stripping away characters' Plot Armor. This tends to overlap with Implacable Man, but where that character is just hard to kill, the Hero Killer must also be a very dangerous threat. If he becomes too much of a good thing and crosses the line into author wish-fulfillment, he becomes a Villain Sue.

If the series was fairly lighthearted before this guy appeared, then he overlaps with Knight of Cerebus. Compare Don't Ask, Just Run, which can be the reaction to either this or to a non-character situation. He is very often the Goliath in a David Versus Goliath scenario. For a video game example to be a Hero Killer, it must be part of the story; contrast with That One Boss, where this feeling is invoked via gameplay because the player keeps losing.

Anime and Manga

 * Dragon Ball: Frieza. He's so dreaded that even King Kai was terrified of him upon first appearance and ordered Goku to avoid fighting him no matter what. Before we even meet him, he'd already wiped out the number of Saiyans down to single-digits and effectively conquered the galaxy. During the Namek arc, he is responsible for the deaths of:  and directly kills   single-handedly. He even causes
 * Pretty much every major Dragonball villain fits this label, starting with Piccolo Daimao. Good lord, Piccolo Daimao. He was the evil counterpart of Earth's God who went around causing great destruction for the hell of it. It took a suicidal technique from Master Roshi's teacher just to seal him away. When Pilaf releases him, the first thing Piccolo Daimao does is give birth to sons, HeroKillers in their own right. Just one, Tambourine, manages to off Krillin, defeat Goku, and destroy Nimbus. After Goku kills his son, Piccolo Daimao challenges him, and despite his advanced age, curbstomps Goku to near death. The moment that definitely solidified Piccolo's status as a Hero-Killer? When he ANNIHILATED SHENRON.
 * Nappa. So overwhelmingly strong that neither Piccolo nor an enraged Gohan could touch him. He shrugged off a suicide attack by Chaotzu, and a second one from Tien merely blew away his armor. He also managed to kill Piccolo when he tried to blast Gohan. It is immensely satisfying when Goku crushes him.
 * The Androids are specifically designed to be this trope, as they are programmed to kill Goku, and each of them had the power to do so. #17 and #18 in particular are so powerful they utterly terrify TRUNKS, who effortlessly killed Frieza in the previous arc. They defeated every hero in their first battle with them without breaking a sweat. Even Super Saiyan Vegeta wasn't a match for them.
 * There's a good reason Future Trunks is scared of them. In the future, they are far more monstrous. They slaughtered every hero except Trunks, and proceeded to exterminate most of humanity for the fun of it before they are stopped.
 * Cell fits this trope to a T, since unlike other villains, he DID kill The Hero Goku, along with Future Trunks. And before that, he absorbed countless innocents and the aforementioned #17 and #18, just as he was programmed to do.
 * Majin Buu in all his forms is this trope Up to Eleven. He killed off the entire main cast except Goku, all of humanity, and blew up Earth! And before he was even introduced, he already killed or ate several GODS. It took a Spirit Bomb made from the power of everyone on a newly restored Earth to finally kill him, and if it wasn't for a third wish from Namek's Dragon Balls, he would have survived it.
 * Barthomelew Kuma from One Piece. The first time he meets the Strawhats, he nearly kills one of them. Their next encounter initiated a Wham! Episode. That's how dangerous he is.
 * Chief Warden Magellan of Impel Down fits better. He easily defeats Luffy, making clear the latter's pre-emptive strike was no more than a "lucky shot", causing Luffy to pay ten years of his life just to go through the treatment to keep him alive. (This makes Magellan a somewhat literal version of this trope.) He also one-shotted the Blackbeard Pirates, including Blackbeard,, and he proved what an Implacable Man he is when he gave chase to Luffy after he instigated a prison riot, taking out two of the new higher-tier fighters while barely being scratched, and forcing even Jinbei and Crocodile to run for it. Luffy fights Magellan again with protection from Magellan's poison, but Magellan just unleashes a poison strong enough to dissolve Impel Down itself, thus upgrading to an Advancing Wall of Doom and making escape from the prison the only viable option.
 * The Three Admirals also play this role, especially to the Straw Hats. They are regarded as the Marines's "Greatest Force", and for good reason. Their appearances are often marked by expressions of shock and unrelenting terror on the faces of every pirate unfortunate enough to bump into one of them, and said appearances are also marked by mind boggling displays of sheer power, and at least one No-Holds-Barred Beatdown.
 * Dio Brando from JoJo's Bizarre Adventure Part 1. Even Speedwagon was afraid!
 * In part 3,
 * Neart the end of Jojo part 7, Steel Ball Run, we have
 * Scar from Fullmetal Alchemist is introduced in this fashion. He kills many high ranking alchemists, and shatters Ed's arm the first time they meet. The Homunculi never lose this title.
 * Special mention goes to Wrath/ Of all the villains, he has the highest count of likeable characters killed ; most people just run after seeing him. Scar's Evil Counterpart, Kimblee could also count. While he doesn't freak everyone out to the degree that the Homunculi do, his reputation alone has everyone on edge, until an entire base occupied by a Badass Army is plotting ways to try and kill him..
 * And then we have Colonel Roy Mustang who pretty much serves as a Hero-Killer Killer. Both of his fights with one of the Homunculi have been utter Curb Stomp Battles, and a
 * In the 2003 anime version (which went in a very different direction from the manga) Scar retains his Hero-Killer status for much of the show. Envy is another very good example, murdering numerous named characters, dancing pirouettes around the heroes during combat, and ultimately during the climax. If you see Envy, book it.
 * But, Envy being Envy, You Won't.
 * Whenever Ali Al-Saachez of Mobile Suit Gundam 00 shows up, you can be sure there will be much asskicking towards the heroes involved.
 * By the second season, however, Ali Al-Saachez has been downgraded from Infinite effectiveness to only High, thank to his first defeat at the hands of his enraged mortal enemy, Setsuna F. Seiei. Eventually, his threat against humanity ended for eternity with his Karmic Death at the hands of the second Lockon Stratos.
 * When you think Gundam, THE Hero-Killer by default is Yazan Gable. No doubt about it. He's killed how many named characters, again?
 * Two:
 * What?  doesn't count? Sure   was hit by shrapnel, but who made the shrapnel in the first place?
 * Yazan also arranged for the death of Jamaican and one of the Argama's Bridge Bunnies. He also came close to killing Kamille several times, warded off only by the interference of the other Argama pilots.
 * And then he kills  in the beginning of ZZ Gundam!
 * There is a mini-arc in Naruto that introduces the Akatsuki organization by sending two of it's members to Konoha. A few fights ensue, and they toss many of the most powerful main characters around like rag dolls, even leaving the legendary Kakashi Hatake with psychological damage for some time. They continue their rampage until Jiraiya (who is so powerful that the only reason he isn't Hokage is that he doesn't want to be) shows up and chases them off.
 * Orochimaru is introduced this way as well, but we aren't shown the full extent of his power until much later (and he was just screwing around with two rookies when he was introduced).
 * Special mention goes to Pain. And while at it,
 * Inverted in Hunt for the 8-Tails and Kage Summit arc, when Killer Bee and the Kage acted as Villain Protagonist Killers to Taka.
 * And now there's
 * Lord Darcia from Wolf's Rain becomes this in the final episodes.
 * of Bleach has summarily destroyed, annihilated, curb stomped and effortlessly flicked away just about every hero he's gone toe to toe against. . If Yamamoto isn't up to the task, if Ichigo can't take enough levels in badass to defeat him, if Isshin is stumped by his transformation, and if  can't defuse the situation, we're entering an Only the Author Can Save Them Now situation. One wonders why he even needs to be a Magnificent Bastard.
 * Looking at the proportion of problems he solves through brute force to problems he solves by actual planning, chances are he isn't one.
 * The author kind of admitted making him the big bad was an Ass Pull decided on after his "death". The plan was probably to make the snake-motif jerkass (Gin) the Big Bad at that time.
 * While nearly all of the filler villains are Aizen ripoffs, the only one who really reaches this status is the villain of the 4th move, Hell Chapter.  Ichigo has a breakdown a few scenes later, not sure if he can beat him even if he goes Full Hollow, which he can't because it's all part of his plan.
 * There is an unseen member of Vandenreich
 * Anytime Kazuo Kiriyama shows up, everyone you are rooting for is going to die.
 * Pretty much any incarnation of Astro Boy has Pluto, whose entire function is to destroy the most powerful robots on Earth.
 * Fate Averruncus in Mahou Sensei Negima. Not during his first appearance, though he did have everyone completely outclassed then. No, it's actually when
 * Also Tsukiyomi for Setsuna who beat her only because she knocked her glasses off.
 * The Huckebein family from Magical Record Lyrical Nanoha Force starts this way, first by trashing the new main character(despite the fact that his Heroic Resolve allows him to properly use his newfound powers) and let him live only because his attacker "runs out of ammo". They then send one of their craziest members to . Also, before and after both mentioned events they're named and referred to by a lot of characters as very dangerous and threatening people. They cemented their status as this when their apparent leader.
 * Asura from Soul Eater is his first appearance curbstomps Black Star and Death the Kid with a couple of flicks.
 * The Oracion Seis in the beginning curbstomps the magical Alliance
 * And later curbstomps Team Natsu minus Erza.
 * No heroes actually die in either example. The only named character to die so far was killed by.
 * The current arc may well be the one to take Fairy Tail Darker and Edgier. The heroes have been getting beaten soundly throughout, including MAKAROV, at the hands of Hades and his guild.
 * Update to the above.
 * You know why no one have died yet?
 * Acnologia, the Black Dragon of the Apocalypse. This is the dragon that crippled Gildarts.
 * In Chapter 253 he takes this to a whole nother level by
 * Puella Magi Madoka Magica's Walpurgisnacht may be an example,.
 * Charlotte gets some credit for being able to  On the other hand, Puella Magi Oriko Magica proves that it's only because
 * Treesea in Yumekui Merry curbstomps virtually everyone who faces her.
 * In Blassreiter, the first time Xargin shows up, he effortlessly wipes the floor with Joseph and a recently-amalgamized, even going so far as to put the latter into a coma which takes most of the series for him to recover from. The second time he gets in a fight, he walks straight into enemy headquarters, once again effortlessly wiping out everything in his way, including a newly powered-up Joseph, who had gotten so strong that he had an army of 30,000 demoniaks terrified of him.
 * BlackWarGreymon in Digimon Adventure 02. He is an Evil Knockoff of one of the strongest Mons in the original series, and he is introduced when no one in the main cast has unlocked enough true potential, so the first few episodes after his introduction had him throwing around the Digidestined pretty easily, and he remains a major threat until his eventual . Even when they get get their DNA digivolve forms, BlackWarGreymon still beats them, and is only stopped by Azulongmon.
 * A much more deadly example is Impmon of Digimon Tamers, who is so far the only one in the franchise to have ever killed permanently a partnered digimon . Bonus points for carrying out a No-Holds-Barred Beatdown beforehand on the heroes,.
 * The Big Bads in Sailor Moon often embody this. The first, Queen Metelia, killed all the Sailor Senshi in her attack on the Silver Millennium and was only stopped by the Heroic Sacrifice by Queen Serenity. Death Phantom, in the future, when he recruited the Black Moon clan, launched an attack that the future Sailor Senshi weren't able to stop. By the end of the series, we have Sailor Galaxia.
 * Trude from Otogi Juushi Akazukin. Her first appearance consisted of her Curb Stomping all three Musketeers and turning almost everyone in the group into dolls. When they finally break free of the curse, they go for a rematch, where she still No Sells everything they throw at her, prompting the group to teleport away in desperation. The next time they fight her, it's with the help of an Obi Wan who is sufficiently skilled to...bypass the block on said teleportation spell so they can run away again, and it's only with the help of a Mid Season Super Mode that they're able to actually drive her off. Even with the Super Mode Trude is still dangerous, as it only gives them a weapon she can't No Sell, but is still vulnerable to her petrifying all of her opponents.
 * In Eyeshield 21, Hakushuu Dinosaurs centre Rikiya Gaou gains this reputation over the course of the Kantou Tournament, crippling quarterbacks and linemen alike. Forget beating the Dinosaurs—most of the cast spend that arc trying to figure out how to beat Gaou. During the Youth World Cup, the freakishly strong and utterly terrifying Donald "Mr. Don" Obermann takes on this role.
 * The titular Zeiram in Iria: Zeiram The Animation. While Iria spends all of the movies hunting it down to destroy them, the animated prequel shows how it killed and absorbed her older brother and mentor, Glen, who had a been a great bounty hunter of his own right.
 * A rare example on the side of the hero; Alucard from Hellsing. He is more or less this trope to a T, complete with literally everyone in the series of being terrified of him (with very few exceptions), and he wipes out almost every villain with no effort. And he is possibly the definition of the Horrifying Hero; try not to crap your pants when he mercilessly rips apart the innocent police team in OVA III (albiet for a reason other than getting his jollies even though he ended up with them anyway), then parades around their corpses. Literally everything about him is perfect for this trope, save for the fact that he's on the side of the good guys (although calling them the 'good guys' is probably going a little too far).
 * Gauna 487 and Benisuzume kill Guardian pilots by the dozens in Knights of Sidonia. Before their destroyed permanently.
 * A rare example on the side of the hero; Alucard from Hellsing. He is more or less this trope to a T, complete with literally everyone in the series of being terrified of him (with very few exceptions), and he wipes out almost every villain with no effort. And he is possibly the definition of the Horrifying Hero; try not to crap your pants when he mercilessly rips apart the innocent police team in OVA III (albiet for a reason other than getting his jollies even though he ended up with them anyway), then parades around their corpses. Literally everything about him is perfect for this trope, save for the fact that he's on the side of the good guys (although calling them the 'good guys' is probably going a little too far).
 * Gauna 487 and Benisuzume kill Guardian pilots by the dozens in Knights of Sidonia. Before their destroyed permanently.

Comic Books

 * Darkseid. If any regular villain in the DCU can inspire dread and single-handedly turns his mere appearance into a major crossover, it's him.
 * Darkseid's Alternate Company Equivalent Thanos. At one point he literally killed half the population of the universe including many superheroes. At another he literally killed the entire population of the universe including every superhero.
 * Joker is the only person allowed to touch one of the Bat Clan and have it stick for any length of time. It took 20 years to bring Jason Todd back from the dead, and 30 years to de-cripple Barbara. That's got to be some kind of record in the Death Is Cheap DC realm. Heck, even the DC Villains are scared of him.
 * Bane however was the first Batman villain to physically overpower and cripple the Dark Knight. It didn't stick for long, but the sight of Batman broken by a villain was unsettling.
 * Doomsday had this, also in DC Comics, including having won a decisive Curb Stomp Battle against Darkseid, after having killed Superman. That said, his repeated appearances and increasingly nerfed powers have left him decidedly less impressive, culminating with a recent battle wherein he was torn to shreds by dozens of completely untrained Kryptonians. (Now granted, even untrained Kryptonians are pretty dangerous. But remember that, in his first appearance, Doomsday beat not only Superman but also a couple dozen assorted heroes along the way, without ever really stopping to rest.)
 * Doomsday is the poster child for Villain Decay. He was powerful when he fought it out with Superman, when suddenly the writers decided he needed to have character. As if being an elemental force of destruction wasn't enough.
 * In the Marvel Universe there was The Fury, a robot created by an insane Reality Warper for the express purpose of killing all the heroes of an alternate Earth; it succeeded almost completely.
 * Also in the Marvel Universe is Galactus. He eats planets. If you're a non-Terran Marvel character, there's a pretty good chance he's eaten your homeworld (hey, he's gotta eat worlds that matter, but he can't eat the one that really matters).
 * Unfortunately for Galactus, he's been subject to The Worf Effect many, many times. A competent writer can still make him come off as threatening, though. For example, Annihilation had him beaten when he was ambushed by two cosmic beings just as strong as he was. When he recovered, he was not happy, and was pretty much what guaranteed the heroes their victory.
 * Ultron, in the Marvel Universe, a genocidal robot who has wiped out an entire nation on his own. Massively on his own, in fact; on that occasion, he turned himself into an army. And after he had killed everyone in the country, he turned their corpses into cybernetic combat drones to fight the heroes...
 * Later, he tried to pull the same stunt again, only this time he did it with a galaxy. He also cyber-enslaved a slew of cosmic super-heroes and -villains, including the Space Knights of Galador, Gamora (the adopted daughter of Thanos), Drax the Destroyer, Xemnu the Titan, Shatterax, Ronan the Accuser, Nova-Prime and the Super-Adaptoid, several of which qualify as Hero-Killers in their own right.
 * And recently, he returned in "Avengers" in such a way that the heroes - the most powerful hero team in the world, mind - basically were "Oh, no... not again!"
 * In the same vein as Galactus, the Celestials also scare the crap out of everyone whenever they show up. Fortunately, they don't go around eating planets left and right. Unfortunately, they have a nasty habit of "judging" worlds they have seeded life on (which is most of them), and executing them if they don't like what they see. Yes, they execute entire planets.
 * The Anti-Monitor, who personally beat Supergirl to death, after having already eaten hundreds of universes, and went on to be responsible for a scad of other hero deaths. He's the standard by which DCU characters judge "evil" and "dangerous". In a mostly successful attempt to avoid Villain Decay, DC only used him three (and a half) times from 1985 to 2010, a full quarter century.
 * DC has tried to do this with Deathstroke. For the past few years he's been pushed as one of the top villains of the DCU, on a par with Lex Luthor and the Joker. He actually has managed to kill a couple of heroes, including Phantom Lady and the third Atom (and in the trailer for DC Universe Online, he almost kills Batman). Unfortunately, while his powerset (he's basically an evil Captain America (comics) with a healing factor thrown in) should make him utterly terrifying to normals and low-level metas, it's a little more difficult to accept him as a serious threat to the likes of Superman and Green Lantern. His victories against big-name heroes tend to depend on his opponent firmly grasping the Idiot Ball and refusing to let it go (e.g. Flash running straight onto his sword; Green Lantern deciding to swing punches at him instead of, I dunno, flying off and flattening him with a ring construct from half a mile away; or Superman apparently forgetting how his own powers work). Fans have joked that Deathstroke's secret power is a "Jobber aura" that makes his opponents behave like morons.
 * To rub salt in the wound, originally Slade was Genre Savvy enough to AVOID facing superhumans. He just faced the Titans to complete the contract his deceased son had accepted.
 * Willy Pete, of Empowered, is a particularly nightmarish version. His name is a military term for White Phosphorous, and his powers match the name. He's capable of causing an impact as powerful as a nuclear explosion, and generating fire that reaches temperatures as hot as the sun. His favorite pastime is skull fucking people to death as he eats them, not always in that order, and not always before they're dead. Being a fire elemental, he doesn't need to eat. He just likes to. He goes out of his way to only kill D-List heroes and villains, not because he's weak, but because it makes people underestimate him. He likes being underestimated, as it makes people think he's a pushover. He's the recurring nightmare of Thug Boy, due to killing all of his friends.
 * In vol. six, they introduced another hero killer, Deathmonger - a superscience necromancer who has enslaved legions of dead heroes. All the supers are too scared to go after him, for fear of adding to his ranks. He's still not as frightening as Willy Pete. Wasn't this supposed to be a "sexy superhero comedy"?
 * Wonder Woman foe Genocide was created with this in mind. The Secret Society engineered this monster to take out the superhero community.
 * In the Archie Comics Sonic the Hedgehog, the current Eggman (actually an alternate version the first one), was this, managing kill his version of Sonic and the Freedom fighters, and when he first made his big return he conquered Mobotropolis and forced the Mobians to retreat back to Knothole, effectively resetting the series status quo to before Robotnik Prime died, though since then he's gone back and forth between how much a threat he posed. A more extreme case is the alternate timeline where Knuckles became a new Enerjak. He became so powerful that he single handily conquered Mobius and defeated every hero and villain that tried to stop him, even Sonic becoming Super Sonic wasn't enough to stop him. Pretty much the only reason why the Freedom Fighters are around in his timeline when Silver shows up there is because he let the Freedom fighters roam around for his amusement.
 * From the Transformers franchise, we have Bludgeon, a literal Ninja Pirate Zombie Robot. (Seriously, he would have been a pirate in Transformers Animated) In most of his appearances, he's one of the most lethal Decepticon warriors - in the Marvel G1 comics, he eventually ascended to the position of Decepticon leader, and only lost because of The Last Autobot. In the IDW comics, he beat down fan-favorite Soundwave and his casette bots after his own minions, Iguanus and Bomb-Burst, were dispatched. In the Titan UK comics, his Movieverse incarnation is one of only TWO characters to be shown killing his enemies on-panel.
 * In Spider Girl Roderick Kingsley, the original Hobgoblin, becomes this after coming out of retirement. He effortlessly beats down Spider-Girl and her allies with minimal help, kills, wrecks Black Tarantula's organisation, and gets away.
 * Shuma Gorath. Doctor Strange was forced to kill his mentor the Ancient One to prevent Shuma Gorath from entering our world. Then Strange had to kill himself to prevent Shuma Gorath's rebirth. Fortunately, Strange got better. Unfortunately, so did Shuma Gorath.

Film

 * The Agents and Sentinels from The Matrix.
 * The Terminator in the first movie. The only reason the Terminators in the sequels don't count is because the good guys had one on their side.
 * Even when they have one on their side, enemy Terminators are usually powerful enough that they can defeat, if not outright destroy, the humans' Terminator allies. This is especially prevalent in The Sarah Connor Chronicles, where the series makes it clear that Cameron is actually the underdog in most fight scenes involving her and other Terminators.
 * Not to mention the T-800 ALWAYS tell John to run in both the 2nd and 3rd film from the T-1000 and T-X. Its obvious Skynet won't send trash assassins against its biggest nemesis John Connor.
 * Syndrome from The Incredibles builds a robot to kill off superheroes so that he can be the only one left to defeat it and be seen as a hero himself.
 * Dennis from The SpongeBob SquarePants Movie, although quite frankly almost anyone could pose just as much danger to Spongebob and Patrick.
 * Star Wars: Darth Vader.
 * No Country for Old Men: Anton Chigurh.
 * While he's the protagonist, Godzilla falls under this in certain incarnations. Humungous Mecha and in one instance a superweapon that opens wormholes are made to stop him, with little success. In movie we have three other monsters in some prophecy that were supposed to rise to fight him, and he kills them all. Mechagodzilla in its first apprentice during the Showa era also qualifies, easily beating Godzilla in his first appearance and the other monster that was supposed to stop him, King Caeser. Even with the two working together Godzilla has to pull out an odd Chekhov's Gun to win.
 * Destoroyah, a monster born from the one weapon that killed Godzilla in the past. Destoroyah actually kills Godzilla Jr. and nearly kills Godzilla himself.
 * King Ghidorah, Godzilla's Arch Enemy is often played this way, with his mere arrival being enough to send most people into panic. In most of his appearances it takes Godzilla plus an assortment of other monsters to bring him down.
 * The final assassin in Bodyguards and Assassins is a highly-skilled martial artist who mows down pretty much every bodyguard trying to take him on. Eventually,

Literature

 * Lord of the Rings has the Nazgul.
 * And the Balrog.
 * Though at least Balrogs don't go out of their way to chase you, most of the time. Even at their Prime, they're sorta lazy in relation to the rest of Morgoth's army.
 * The Forsaken from Wheel of Time start out this way, before the Villain Decay sinks in. Moiraine estimated any one of them could sense magic being used within a couple of miles, and tear the user apart without even blinking.
 * Though part of this (and part of the perceived Villain Decay) comes from their being preceded by their inflated reputations; they were sealed away with the Dark One 3000 years earlier and elevated from 'mostly powerful but still on a par with the good guys' to 'one step below the devil in all consuming power' in the minds of the people. No one lives up to that, and they do all they can to keep people in awe of them as a strategy because in terms of power and some bits of knowledge, they are no better than the modern day characters. It's also worth remembering that on the day when Lews Therin killed himself, after resealing the Dark One and trapping the Forsaken, he mentions the war had been going on for ten years. Even supposing the Dark One took time to flex his muscles and impact the world after the bore was made into his prison, the fears of instant death for all should he be released by many characters would therefore seem exaggerated. Next to that the Forsaken's supposed powers look even more ridiculous than they already were.
 * A few of the forsaken keep this title even after it's revealed they've been deliberately bolstering their reputation. Ishamael/ is always bad news, and Lanfear was horrifyingly destructive if you got on her bad side. Demandred, too- he hasn't done much on page yet, but per Word of God he's going to have a big role in Tarmon Gai'don, not to mention being the only Forsaken to take over a nation (we're not yet sure where) and stay both unrevealed and in power for the course of the series. Say what you will about the competence of most of the Forsaken (and you can say some pretty unkind things), these three at least have their act together.
 * Shaidar Haran from the same series is an odd variation; he's never confronted any of the heroes directly, but his job is to act as the Dark One's mouthpiece and enforcer among his minions, so it's the villains who know they're in deep when this guy shows up.
 * The Mirror from Day Watch, who killed  by literally stripping her flesh from her bones after incapacitating several other high-level Night Watch magicians.
 * The Lord Ruler from Mistborn, figuratively and literally, as he takes down  effortlessly immediately after the latter has his Crowning Moment of Awesome by killing an Inquisitor.
 * In New Jedi Order, The Yuuzhan Vong basically have this (with a healthy dose of Combat Sadomasochist on the side) as their hat.
 * Even among the Yuuzhan Vong, the voxyn are notorious for this. They're introduced casually hunting down several Jedi and only go up from there. The mission to kill the voxyn queen has the single largest Mauve Shirt casualty count in the series and kills no less a hero than.
 * Nicodemus from The Dresden Files. He has killed at least a hundred Knights of the Cross and only two have ever gotten away with their lives, and of those, one was permanently crippled.
 * The one who escaped without being permanently crippled so angered Nicodemus that even after Nicodemus  Nicodemus was willing to give the good guys a chance to stop his plan to   just to get the guy's sword, Fidellachius.
 * The Eldest Brother Gruff also has these trappings. Hitmen for the Summer fae, each one defeated by Harry swears his elder brother will come after him, just like in the fairy tale.
 * Jared Kincaid, an ostensibly non-magical humanoid something that has been in the business of assassinating supernaturals for centuries. Probably a good thing he is currently on a permanent bodyguard duty for the above-mentioned Archive.
 * Though he hasn't actually killed an heroes on-page yet, Cowl might also qualify. He packs a magical punch stronger than Ebenezar (who's a Senior Council member and the Blackstaff), is a Necromancer even the other necromancers are scared of, doesn't seem terribly worried about being hit by other wizards' death curses, and shrugs off having a car flipped over on top of him like it's nothing. Also a prime candidate for being on the Black Council, though whether he's its leader or just a member isn't established.
 * Leo Bonhart in The Witcher saga, a Psycho for Hire who collects witcher amulets.
 * As of the eighth book of The Malazan Book of the Fallen, Toll the Hounds, Kallor is approaching this. The idea of what he might do if he reaches Darujhistan is so horrifying that Annomander Rake willingly sacrifices his best man, Spinnock Durav, just to slow him down. The fear that other characters regard him with only makes this more obvious. It's a sharp contrast with how they behaved around him in Memories of Ice; it reaches the point where, when Spinnock sees him upset, he actually can't believe it, because, "well, none of it belonged to the legend--to the nightmare--that was Kallor".
 * All the more strange, for the fact, that it is strongly implied
 * In-universe in the Harry Potter books, if you are face to face with Lord Voldemort and your name isn't Albus Dumbledore, you either run like hell or kiss your butt goodbye.
 * Bellatrix Lestrange later became a Dragon form of this with several significant deaths under her belt before she was taken out.
 * A lesser one can be found with Antonin Dolohov, one of Voldemort's tougher underlings. In the first war, he was the Death Eater who slew Gideon and Fabian Prewett, who were both powerful and accomplished wizards. In the second, he almost kills Hermione in Order of the Phoenix and is, according to Word of God, the person who slew Lupin and Tonks in Deathly Hallows.
 * Findo Gask of The Word and The Void who specialises in killing Knights of the Word.
 * In the Sherlock Holmes stories; Moriarty, and Holmes isn't the only one he seriously threatened.
 * Whatever enemy that Eragon fights in the climax of each book tends to turn into this. In two instances, he's needed help,  . In universe, the Ra'Zak and Shades as a whole are built as this, with the Ra'Zak acting as Galbatorix's personal assassins, and Shades, Brom states that prior to the series, there were only two instances of somebody killing one and surviving.
 * And the Ra'zac, who are the Empire's Rider-killers. It turns out that their primary prey is humans, and they have a number of abilities to that effect. Pretty much the perfect weapon for sending after young Riders, or anyone else who Galbatorix doesn't like.
 * Murtagh starts entering this role in the second book, especially at the climax, where he

Live Action TV

 * The evil Priest Caleb from the end of Buffy the Vampire Slayer
 * Spike, when he first showed up, with his history of killing Slayers. In his first battle with Buffy, Buffy survived only because her mother (of all people) intervened with a fire axe and caught Spike off guard as he was about to deliver the killing blow. Sadly, there's a reason Badass Decay was once called Spikeification.
 * Angelus often invokes this, or at least threatens.
 * The friggin Beast of the Apocalypse.
 * Glory. The Scoobies spend the entire season running from her in terror.
 * Almost. Glory's Mind Rape of Tara is what initiated Willow's first Roaring Rampage of Revenge. But the Scoobies still have to plan out literally every single step they take during the final battle with the Hell-bitch (the overall strategy of which amounts to "desperately try to keep her busy without getting killed for a few minutes").
 * Jubal Early the Bounty Hunter in Firefly. He shows up without warning, methodically making his way through the ship, taking down everyone in his path with little difficulty, and makes it perfectly clear that he's not afraid to kill innocent people to get what he wants.
 * Sylar from Heroes, who besides being one of the most powerful characters in the show's mythology has also racked up by far the highest number of main character and supporting character kills.
 * Darkseid on Smallville. Zod might also count, and Lex has been headed in this direction since Season 7 or 8.
 * Inverted on Robin Hood. As the Sheriff's Dragon no one was even remotely afraid of Guy of Gisborne, least of all Marian who played him like a violin throughout the show. Robin and the rest of the outlaws ran rings around him - so no one saw it coming when at the end of season two he.
 * John from The Fades. Before the other characters learn his name, he's known as the Angelic Killer because he's racked up such a high body count. In fact, he's responsible for the deaths of multiple major characters before the end of the first episode.

Mythology

 * Older Than Feudalism: Typhon in Greek myth may well be the Ur Example. The child of Gaia and Tartarus, Typhon was, Depending on the Writer, a god with dozens of snake coils for tentacles, or a towering giant with 100 dragon heads. Either way, he stormed Olympus by himself, defeated Zeus (tearing out his sinews in the process) and drove all the other gods into hiding in Egypt. It was only in the rematch that Zeus was able to defeat him, and even then Typhon wasn't killed--just buried under a volcano, where he awaits the chance to break out again.
 * In Norse Mythology, any of the major players at Ragnarok, including Surtr, Nidhoggr, Fenrir, and Jormungandr could qualify for this trope, given the sheer number of bodies that they leave behind. Fenrir and Jormungandr are likely the two best examples, as they are feared long before the apocalypse goes down, have established rivalries with the gods, and take the two strongest gods (Odin and Thor) with them when they go.
 * In Marvel's The Mighty Thor comics, Jormungandr retains this title. Anytime he shows up Thor is in for a very, very bad day.
 * Surtr is more or less described as one in the mythos proper: "At the end of the world he will go and wage war and defeat all the gods and burn the whole world with fire." He also personally kills Frey in the process.

Professional Wrestling

 * Vader's run in WCW in the early 90s began with him effectively squashing Sting in a decisive fashion, winning the World Heavyweight Championship. He also sent Nikita Koloff into retirement, legitimately broke Joe Thurman's back and beat Cactus Jack to a bloody pulp. He's widely considered the best monster heel in all of professional wrestling.
 * This was essentially the point of Randy Orton's "Legend Killer" gimmick; he severely injured several of WWE's most famous and legendary personalities, in some cases even forcing their retirement. He's recently been doing something similar with his head punt of DOOM, which has put several people on the injured/reserve list for months with concussions. It's wrestling, so you can't quite stretch Kayfabe to cover killing the faces, but Orton comes about as close as you can.
 * Character assassination, perhaps?
 * Mark Henry in his recent heel turn. He took out The Big Show and Kane by breaking their legs with a steel chair and a squash, leaving them out of action for weeks and a few months respectively. He even went to the point of even giving Randy Orton who was World Heavyweight Champion a hard time. The result at Night Of Champions? He becomes World Heavyweight Champion!
 * Before that, he had taken out the like of Kurt Angle, Chris Benoit, and Batista.

Tabletop Games

 * Jasper Stone in Deadlands (the dude on the cover of the main book). He ends up specifically assigned to this role by the Big Bads.
 * Dungeons and Dragons
 * It's only level 20, but the Heroslayer Hydra in 4e is meant to fill this role. It's designed to make "tank and spank" strategies useless or near-so by dishing out a lot of damage from multiple attacks, and getting a large damage bonus against anyone who "marks" it and tries to force it to attack them. The ability is appropriately enough called "heroslayer."
 * Mephistopheles from 4th and older editions of D&D. Other archdevils do as well, but Mephistopheles is the most visible.
 * If an entire dungeon can count, the classic Tomb of Horrors module and Forgotten Realms' Undermountain definitely belong on this page.
 * The Tarrasque was created as basically the single most powerful monster in the world that didn't live in another world. It was essentially Godzilla for the D&D. It had resistance or immunity to a great deal of attacks and had a number of special rules that made characters have to jump through a variety of hoops to kill it and make it stay dead. In practice, however, players found a number of weaknesses, such as its lack of ranged attacks and vulnerability to energy draining, causing many hardcore fans to brag about the time they killed the Tarrasque.
 * Orcus was supposed to be this in 4th Edition, but this mostly led to people custom-building parties to beat him and then bragging about it.
 * Dragons also tend to be more powerful than their Challenge Rating would suggest, partly so that encounters with them would be more memorable.
 * Elminster, the iconic wizard of the Forgotten Realms setting, was not intended as an encounter for players, but because his official stats are available, many players try to pit themselves against him. Dragon magazine got tired of players writing in to tell them that they had slain Elminster, so it included a mass response saying that Elminster was way too smart to be killed and that he was playing a trick on the player characters.
 * This is the point of the 'character-killer' build for heroes in Warhammer Fantasy Battle and Warhammer 40000. The Eldar Farseer's Mind War psychic power is a particularly good example.
 * Skulltaker from the Daemon books is quite literally made for this. The fantasy version has Killing Blow on 5+ and the 40k version wounds anything and inflicts Instant Death on 4+. Of course, a significant amount of characters are immune to Killing Blow or Instant Death, which reduces his utility somewhat.
 * The fantasy version also had Karnak, an who had the ability to mark an enemy unit and re-roll and failed hits or wounds against it.
 * The Blood Angels's Sanguinor has the ability to choose one enemy Independent Character and re-roll To Hit and To Wound dice in close combat against said character for the game's duration.
 * Also from the Blood Angels is Mephiston, who has an ability that forces an enemy character in contact with him to take a leadership test with a minus 4 modifier, and he gets to re-roll any failed To Hot and To Wound rolls for the round of combat if they fail, which coupled with the fact that he has Force Sword, means whatever he's fighting is likely to die in that unless it's not immune to instant death. Of course, Mephiston is strong that enemy characters will generally die against him regardless.
 * The 5th Edition Tyranid codex brings us the Swarmlord, a unique Hive Tyrant that the Hive Mind reincarnates when a hive fleet can't beat its prey through normal means. Not only is the thing a cunning strategist, it wields four energy-charged swords, and was capable of beating Marneus Calgar, Chapter Master of the Ultramarines, in hand to hand combat (given, Hive Tyrants are large, so that may not be as hard as it seems).
 * In game, the Swarmlord follows this in that is swords force an enemy to re-roll successful invulnerable saves and inflict instant death, though the Swarmlord is so expansive it's probably only worth using in an Apocalypse game.
 * The 7th edition Warriors of Chaos rulebook tends to somewhat encourage keeping hero killing in mind when building an exalted hero or chaos lord since they can roll on the eye of the gods table and, likely, get stronger from it. Oddly a Chaos Lord getting rolls on this makes him stronger than a Daemon Prince.
 * Exalted features one of these in the corebook in the form of Octavian, a Second Circle Demon. For comparison, the Solar Exalted are designed to be bastions of good, the righteous god-kings of Creation, with all the corporeal and celestial power that comes with the office. Octavian carries three of their severed heads on his belt- and as a Second Circle, there's all the Third Circle Demons above Octavian even before you reach the Yozis...
 * Hilariously, due to the glitchy nature of early Second Edition, he's only a mild threat, and thanks to sorcery, it's quite possible he never actually gets as far as a fight-a comic has an impatient Arianna blast him with Adamant Circle Banishment, sending him screaming back to Malfeas. One assumes he doesn't consider being banished an actual loss, since his opponent cheated. A better example would be the Wyld Hunt, the organization of Dragon-Bloods devoted to, among other things, killing Celestial Exalts before they become a threat to the Realm.
 * The Necessary Evil RPG, in which the Super Villain PCs are La Résistance on Vichy Earth, has Hero-Killer ammunition, known as HK rounds. Basically, bullets designed for killing people who are Immune to Bullets.
 * Mechanically speaking, Tsabo Tavoc of Magic: The Gathering. Her abilities stop other legendary creatures from damaging, blocking or even targeting her at all, and she can kill them easily with her activated ability. In the storyline, Gerrard beats her, despite this being all but impossible in-game for the aforementioned reasons.

Video Games

 * This trope is often invoked in the Hopeless Boss Fight of any game.
 * The Black Knight from Fire Emblem: Path of Radiance. You could choose to fight him in the earlier levels where he shows up, but it suggests that you flee, and for a very good reason. Every single character you throw at him will be unable to dent him and will soon find themselves dead in one blow. Only towards the end of the game does it let you know that you are ready to face him, but even then it's one hell of a challenge.
 * Orbital Frame Anubis is introduced at the end of Zone of the Enders: despite having just taken out The Dragon, it's made abundantly clear that Jehuty facing off against this thing would be suicide. You don't get a chance until the sequel, and the bulk of that game is spent finding a way to even the odds—the first few times you run into each other, your only real option is to avoid dying until you can escape. By the time you're ready to face it, it and its pilot have gone into One-Winged Angel mode.
 * Metroid Fusion adds a Survival Horror bent to the game by setting up fixed encounters with the SA-X, a malevolent Samus clone created from her parasite-possessed power suit. Most of these encounters can be avoided with stealth and caution, but if you attract the SA-X's attention - and unavoidably in one case - then your only option is to run for your life. The situation is exacerbated by the fact that Samus' Fusion Suit uses cold-vulnerable Metroid DNA, and the SA-X happens to have Samus' Ice Beam equipped.
 * Dark Samus, especially Metroid Prime 3. The game introduces three other bounty hunters.
 * Barbatos Goetia from Tales of Destiny 2. The first and foremost thing he's known for is killing the prequel's hero Stahn and he's off to claim the heads of other heroes, namely Philia and Garr. His legend as a Hero-Killer has even stretched to Tales of Vesperia, where he reappears as a bonus opponent in the battle arena and his name is Killer of Heroes. Indeed, it turns out that . Nothing less can be expected of one voiced by Norio Wakamoto.
 * Metal Gear Solid 2: Sons of Liberty has Vamp and Fortune.
 * Fox Face in the original Shadow Hearts.
 * Suikoden II's Luca Blight.
 * And Yuber to a lesser degree, especially in III.
 * Childrich of Suikoden V can also serve as one, particularly
 * Nyx from Persona 3. tells the heroes, at least half a dozen times, that "Nyx cannot be defeated."
 * Five words: "Be careful, I sense Death!" The Reaper will chase you down and annihilate you as early as the first floor if you spend too much time dawdling on a single floor in Tartarus. Even when you get to the end of the game, right up to the final boss, he'll only downgrade from an unbeatable foe to an extremely difficult one without either a serious amount of level grinding or the Armageddon fusion spell. And EVERYONE knows how monstrous the Reaper is, as evidenced by your allies special 'I just got in a fight on my own' lines, and Fuuka's standard pre-battle lines instead urging you to run like hell.
 * Alma in F.E.A.R.. It kind of helps that bullets do jack against ghosts.
 * Alma is a special case in that she's an accidental Hero-Killer. In F.E.A.R. she just wants to HUG Point Man because he's but her presence is so lethal that even such a harmless action can kill. It's kind of heartbreaking - all she wants is a hug, but letting her do that will kill you, so you have no choice but to shove her off. And in Project Origin she's . That, incidentally, is also why at several points in the game she actively lashes out against anyone who's even looking at you funny.
 * Mass Effect:
 * The Collectors and Harbinger in Mass Effect 2. From the first scene, you know they're bad news when they kill your character from the first game. Granted, s/he is revived by a secret project, but it really sets the tone. In the final mission against them, it's possible for everyone to die, and, without excellent planning, at least one or two characters will die.
 * Harbinger nearly does it again in the third game when
 * Mass Effect 3 gives us Kai Leng, who had previously made a name for himself in the Mass Effect novels. For those who didn't read the novels, though, Kai Leng needs to be given a chance to show how badass he is.
 * Your first meeting with him, he has at hand-blast point. If you are new to the series, he kills  and there's nothing you can do.
 * If is available, but not, he will save , but Kai Leng will kill him, even though.
 * And if is alive, he also stops Kai Leng from killing, and they begin to fight.
 * Then
 * Later, on, you get to actually fight him, but
 * In the Sanctuary mission, he will kill
 * Finally, you get to have a boss fight with him when you . When you finally beat him,
 * Super Robot Wars has Shu Shirakawa's Granzon, although it tends to play the role of villain killer more often. It appears several times early in each continuity as a (mostly) Hopeless Boss Fight. Fortunately for the heroes, Shu has a vaguely-defined interest in keeping them alive, so he tends to hold back while testing their abilities. However, his Curb Stomp Battles with villains much later in the Sorting Algorithm of Evil prove the heroes' suspicions about how screwed they'd be if he wanted them dead. By the time the Lensman Arms Race finally catches up to him, he joins as a temporary party member,
 * Resident Evil 3 has Nemesis. While it's posible to beat him every time he appears, he just keeps coming after you, and the best choice for non-pro players is to simply run away.
 * Final Fantasy VII: Sephiroth. While  in the game, it's really in the movie Advent Children that he shows the power backing up his claim for the title. As soon as he appears, he forces Cloud to stretch himself to twice as superhuman feats as he has so far (and that's saying something), while he himself doesn't even get out of breath. Especially in the extended version, where he beats Cloud within an inch of his life before the inevitable Heroic Second Wind kicks in. Cloud has already defeated opponents like the ridiculously powerful Remnants of Sephiroth and a gigantic dragon god, but his reaction upon first seeing Sephiroth can be described as "Eep!"
 * Lavos from Chrono Trigger
 * Sin from Final Fantasy X. Cuts a swathe of destruction and leaves nothing but ruins in its wake wherever it treads. Still, that does not deter the many organizations that rise up to Spira's defense and try to defeat him..
 * Witches in Left 4 Dead. Normal zombies, even in a horde, are fairly easy to survive; smokers and hunters are usually just an annoyance; tanks are deadly and very scary, but an effective team can take them down without getting hurt; but the only appropriate response to a witch is Don't Ask, Just Run.
 * As time goes by and people learned proper tactics for handling witches, serious Villain Decay set in. High level players outside of tournament matches have made a sport of killing witches in the most outrageous ways possible, such jumping over her, spinning around, and shooting her point blank with a shotgun for an instant kill. In competitive play, if something's going to kill an entire team of survivors, it will be a tank.
 * Doppelgangers in .hack//GU.
 * Tri-Edge/Azure Kite. The dude is just... plain... unstoppable. Pretty much every appearance he makes involves someone getting Data Drained and comatose. He's only defeated twice in the series, which barely slows him down at all.
 * Starcraft: Kerrigan.
 * Arthas Menethil, The Lich King, from Warcraft and World of Warcraft. He killed many named characters and many of them are badass in their own right.
 * Although it comes back to haunt him in a big (not to mention literal) way. His runeblade Frostmourne steals and entraps the souls of everyone it kills (oh, and his, too). At the climax of his encounter in Wrath of the Lich King
 * Mephiles the Dark from the infamous Sonic the Hedgehog 2006. In the Last Story,
 * LeChuck from the Monkey Island series. Though he plunders, tortures and even kills hundreds upon hundreds of people (and even forms his own skeletal army from these corpses), his plans to rule the entire Caribbean keep getting thwarted upon many defeats (and deaths) at the hands of the main protagonist Guybrush Threepwood. It is not until Tales of Monkey Island that,
 * In Mortal Kombat 9, becomes one for all of thirty seconds.
 * Earlier on in 9,
 * And then, back in Deadly Alliance Shang Tsung (with the help of Quan Chi) killed Liu Kang, starting a multi-arc Wham! Episode spanning DA, Deception, and Armageddon.
 * ZODIAC Virgo from RefleX.
 * Everytime Vladimir Makarov appears in the flesh, without exception, a Player Character either dies or gets critically wounded, usually along with other important characters as well. He, he  , he  , he   and   at the end of the third Modern Warfare game. Basically, anytime Makarov appears, it is bad news.
 * Amante Furlair in ZoE Fist of Mars who is either directly or indirectly responsible for every single notable character death aside from  and she's only 15. Amante is essentially the Azula of mecha games. It's a real shame the cast has not appeared in SRW, as she'd likely have a reputation equivalent to that of Simo Hayha with a Colony Drop being the first response to any sighting of her. She even mindrapes then kills Team Pet bishounen Philbright, turning him against you before discarding him as being useless as a pilot. And to top it all off she gets away with it all too because Kojima got too wrapped up doing endless spinoffs of Metal Gear Solid to have time to return to ZoE! In the end  While she isn't totally successful, considering the player's team is the only opposition remaining on Mars it's a good bet the BIS would have had an amazing uphill battle of Sisyphusian proportions.
 * General RAAM from Gears of War. He kills Minh Young Kim in his very first cutscene, and then, in the RAAM's Shadow DLC, he
 * Thanks to Hyrule Historia, Ganondorf has ascended to one of these in an alternate timeline spawning from  Notably, while his Hero-Killer status is often challenged, he's offed more than his fair share of highly significant characters, including the sages from Wind Waker (forcing Link to seek out replacements) and   from Twilight Princess. Subverted in Wind Waker, where he soundly thrashes Link and Zelda in their first fight, only to spare their lives in a rare Pet the Dog moment.
 * The Dahaka in Prince of Persia: Warrior Within is a being whose only point in existence is to be this. When a being somehow avoids their own fate, in and of itself a rather admirable fate, a Dahaka is created to destroy them. The Prince can only defeat it with the Infinity+1 Sword; otherwise he cannot even harm the beast.
 * The Dahaka is so well known for this, a lesser-known band called Merkabah actually has a song about it, appropriately named: "Dahaka". A transcript of the Metal Growled opening (lyrics are difficult to retrieve on the internet, and no easier to understand): "Sometimes it was whispered; sometimes it was read: the secret incantation that filled with the enemy with dread. If you knew it, if you used it, you could reach back to [unsure]. But stop and [think?; if one can see it]: Sole Master Of Your Destiny You Would Be. Dahaka is released. Dahaka: the Guardian of the Timeline. [A sentence; possibly "Eternal pursuer for fiddling with time."] NO ONE ESCAPES THE DAHAKA."
 * In Warhammer 40,000: Space Marine Bigger Bad Nemeroth kills Brother-Sergeant Sidonus.

Webcomics

 * Jack Noir, the Big Bad of Homestuck, fulfills this role, along with being the Knight of Cerebus. So far, his tally of protagonists killed includes . He also killed his own king and queen, slaughtered two entire armies, destroyed three inhabited moons and twelve planets (the latter offscreen) as well as . Also inspires similar fear amongst the trolls, though his kill count is considerably less than Jack's with only  in this timeline and  in a branch timeline.
 * His Alpha-universe self is no slouch, either
 * Lord English didn't waste his time offing normal characters. Instead, his very first kill was
 * Kore from Goblins was feared by the main cast of goblin adventurers even before they had met him. In their first encounter with the dwarven paladin, they were barely able to wound him. Notably, that fight ended with the death of.
 * Xykon from The Order of the Stick
 * It ought to be noted that
 * Lord Dragos from The Beast Legion falls invokes fear in everyone he comes across.
 * Lord Dragos from The Beast Legion falls invokes fear in everyone he comes across.

Web Original

 * Deathlist of the Whateley Universe. He's got the name because of the huge list of superheroes he has already killed, including Champion. The only person we know of who has survived this killer cyborg is Lady Astarte in the Halloween story, and she had help from . She still couldn't polish him off.
 * Mecha Sonic of Super Mario Bros Z. Every single fight he's picked with the heroes has been a No-Holds-Barred Beatdown, starting from his first appearance where he very nearly killed Yoshi. Then later on with two chaos emeralds, he utterly annihilated the Koopa Bros. and the Axem Rangers within about two minutes of each other before completely wiping Yoshi's Island off the face of the Mushroom Kingdom. The heroes only narrowly managed to escape the same fate through a conveniently-placed Super Star, because not even Shadow could scratch him in a straight-up fight. And that's not even including what Mecha Sonic did to everyone on Mobius in the backstory...
 * The Meta from the Red vs. Blue Recollection trilogy, especially in the first part of the trilogy (Reconstruction) and the final episodes.
 * Lilith from Shadowhunter Peril. Her wrath is inescapable, and every single character knows that when she appears, it is time to run. Even Valentine knows that he shouldn't mess with her. She is one of the few characters in the entire story that can fight on equal terms with an angel (and possibly win). She is completely ruthless and has absolutely no qualms about killing any of her own family: she shoved her hand through her son Umbra's chest, and squeezed his heart till it exploded, then dropped him unceremoniously onto the ground and laughed, all just so she could psychologically disturb the watching Resistance.
 * Oblivion has no surpassed Lilith as the Hero-Killer of Shadowhunter Peril. While Lilith is powerful in her own right, it's revealed that she CAN be defeated by Umbra and Nicholas if they work as a team (Umbra distracting her while Nicholas powers her up and then hits her with a dragon made completely of fire and wind). Oblivion is no such thing. He beat Umbra within an inch of his life and tossed Nicholas aside. Even Puriel, who is the most powerful character on the Light side, is pushed to his limit whenever he meets Oblivion. It's really shown in the final battle, where Oblivion effortlessly kills Ra (a giant phoenix god-king who commands an impressive army of 9-foot-tall phoenixes) in the first few moments of the final battle. Then he finally kills Nuriel, an angel of God who is, for all things considered, Shadowhunter Peril's God of Blizzards. This manages to drive Puriel into a Heroic BSOD. When Puriel snaps out of it, his ensuing battle with Oblivion rips up half the city and it only ends when Puriel manages to rip out Oblivion's heart and then finally kill him. And even then, there's evidence that he might not be totally dead.
 * Abbadon is also shaping up to be one of these, what with being the Demon of Destruction and all.
 * Levi Cole in The List is a professional super hero assassin. Though many heroes underestimate him, his reputation seems to have grown since the beginning of Season 2; when he killed

Western Animation

 * General Grievous in Star Wars: Clone Wars. Unfortunately, the Worf Effect part of this trope is in full effect; his appearances in later media (including Revenge of the Sith itself) have been far less Badass.
 * The Worf Effect included having his vitals turned into chunky salsa by Samuel L. Jackson. He shouldn't even have been alive, much less being able to fight off Obi Wan for a good ten or so minutes.
 * Apparently, this retcon was only conceived because George Lucas' interpretation of Grievous was that of a mustache-twirling Smug Snake, not the Jedi-slaughtering cyborg from the series.
 * Trigon from Teen Titans. Slade became something of one after getting a bunch of powers from Trigon.
 * Even before that, Slade was one of the only villains the show took dead seriously.
 * Dungeons and Dragons had a one-shot villain, the Evil-With-No-Name, in the episode "The Dungeon At The Heart Of Dawn." A being so powerful even The Dungeon Master and resident Big Bad Venger couldn't handle him, who could soar the cosmos and return to plague the realm at any time he chose, who could only be fought...maybe...with All Your Powers Combined? The fact that he only appeared that one episode is a shame.
 * Nox, the Big Bad of Wakfu. His strongest creation, the clockwork monster Razortime, manages to become this trope in one episode. The moment it appears, the heroes realize it's really bad news. All of their efforts are pretty much useless against it ..
 * Vlad Masters from Danny Phantom.
 * A bigger example still is Dark Danny from "The Ultimate Enemy," who effortlessly defeated not only Vlad, but the rest of Danny's Rogues Gallery. He even, albeit in an alternate timeline.
 * Oberon, in Gargoyles, hands down the most powerful being in-universe the Gargoyles face. Even the combined strength of the clan, Xanatos, Fox, Reynard, and Puck couldn't stop him.
 * The enchanced Archmage also had shades of this, taking a villain who was already one of the show's rare Complete Monsters and adding power nearly equal to Oberon's on top of it. He was stopped, but only through his love affair with the Villain Ball and the fact that Goliath figured out his Achilles' Heel.
 * The Energy Monster in episode 18 of Sym-Bionic Titan qualifies as this. The heroes were completely powerless against it because it was completely impervious to their attacks and could drain the energy out of machines and permanently drain the life out of them so they couldn't be recharged (considering the heroes use robotic battle armor and one is a robot, you can see why this counts).  It takes the full fire power of the G3's ship and the explosion of the space station it was in to finally destroy it.
 * The Skullmaster from Mighty Max. In the series backstory successfully conquered the Earth, and Max's predecessor couldn't beat him and was only able to seal him in the center of the Earth. Most of the appearances he makes have the heroes doing some running from him, and in the finale he kills both the supporting heroes and the most Max could do was create a Gainax Ending
 * Vilgax from Ben 10. Word of God is that his atrocities include destroying 4 planets and creating a black hole, and the dialogue in the series indicates that everyone is scarred to death of him. When he first starts to act at the end of the 1st season, Ben's Badass Grandpa tells him to run when he sees him, which turns he should have as Vilgax promptly stomps him. When he makes a return in Ben 10 Alien Force, though for reason acting under rules of Galactic Conduct, these rules mean he gets to fight some champions from a planet and if he wins, the plant is his. Till returning to Earth, he never lost.
 * In the 2k3 TMNT, the Shredder maintains always manages to maintain himself as the turtles most feared enemy, notably in part because they're never able to beat him without any outside help. Special mention to the fact that he's actually beaten them on two instances despite them having Splinter with them
 * The Rowdyruff Boys.
 * The immortal martial arts master Chase Young from Xiaolin Showdown isn't so much a hero killer, than a Hero "Defeater". Anyone he defeats becomes another one of his big cat minions (tigers, lions, panthers, etc.). He does this temporarily to Omi, who is forced into his service as a cat, until he and his team defeat him and restore everything to normal.