Diabolus ex Nihilo

"Arthur! Monkey out of nowhere!"

— The Tick

Sometimes you have a goal in mind for your story, but you have no idea how to get there. For those times where the end justifies the means there is the Diabolus ex Nihilo or "Devil from Nothing". The Diabolus ex Nihilo is an enemy so foul, so horrible, and so evil that it needs no Backstory or reasoning. It just appears from nowhere, does its job of shaking things up and antagonizing the heroes, and then promptly dies. The Diabolus ex Nihilo may get a back story in the future, but it could just be an exercise in retconning.

This trope can often appear in origin stories where it's more important that the characters are introduced than that they do something sensible.

See also the Giant Space Flea from Nowhere, which serves roughly the same function in Video Game gameplay — a boss that pops up at the end of a level for no narrative reason and with no explanation, just because there's supposed to be a boss at the end of the level or the game.

Compare the Generic Doomsday Villain, who has no clear motive for their actions other than being "evil," even if they do in fact have backstory or context. Contrast Start of Darkness, where the villain's backstory is explored in full detail, and Outside-Context Problem, where the mystery behind a villain's origin, motive, and abilities are the source of their threat. Consider Invincible Villain, where them just showing up exemplifies how bad things can get. A Diabolus ex Nihilo used by a writer to get out of a corner may be an example of Chandler's Law.

Yes, this may also be a Diabolus ex Machina if it succeeds in doing some damage. See also the Anthropic Principle where the appearance of an otherwise unexplained baddie forms the premise for the entire story. If they appear in the backstory or disappear as quickly as they appeared, they may overlap with Unknown Character.

See also Ass Pull and Unspecified Apocalypse.

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Examples:

Anime and Manga

• Digimon:
  • Digimon Adventure. Apocalymon, the final villain, literally shows up out of nowhere in an outer space-like battlefield and is fought and defeated within the course of two episodes. Apparently this was actually a case of Executive Meddling, and there was supposed to be far more leadup to Apocalymon, as well as his relation to the Dark Masters.
  • In Digimon Adventure 02, Daemon and his followers appeared randomly, have incredibly vague motivations (they want the Dark Spores... for some reason), and are defeated in a few episodes after causing some pointless mayhem. They are then quickly forgotten. The manga version is slightly better about this, in that Daemon is on Oikawa's side rather than against him.
  • In Digimon Frontier, after seemingly defeating Cherubimon and destroying his fortress, the heroes fight an IceDevimon who was imprisoned there for terrorizing villages. The lack of hinting towards this and his relatively quick defeat suggests that his only purpose was to fill up half an episode.
• Dragon Ball Z: Despite Frieza being one of the most important villains in the franchise, he does not have much of a backstory. His race has never been identified, nor have we ever learned what planet he is from. All we really know is that his family has been running an intergalactic space pirate organization for a long time.
• GaoGaiGar: The Zonuda shows up practically out of thin air in the final episode with little foreshadowing. The "almost" is only there because the last On the Next hinted that the fight wasn't over just yet.
• In Hellsing: The Major has no backstory and no motivation until he meets Alucard and wants to destroy him simply for being different from him other than because he simply enjoys war.
• In JoJo's Bizarre Adventure: Stardust Crusaders, Vanilla Ice is introduced near the close of the Part right before fighting the heroes. His Stand, Cream, is one of only three (his, Holly's, and Kenny G's) that is neither a Tarot card or Egyptian God and it can destroy anything it comes in contact with. In addition, he's also a vampire. The end result is that he kills Avdol in seconds and kills Team Pet Iggy over the course of the fight, and wounds Polnareff so badly before dying that he's unable to assist much during the final battle with DIO.
• Junji Ito has a lot of these sorts of beings in his works, with very little explanation behind them and little resemblance to anything from myth or legend. It actually works to make them all the more terrifying, especially in the case of things like an army of zombified fish emerging from the ocean on mechanical legs, a planet-eating abomination from another dimension, people-shaped holes in the side of a mountain, and a curse surrounding the very concept of the spiral shape. We get some speculation from characters, but rarely, if ever, any definitive answers. The less we know, the worse we feel.
• Mobile Suit Gundam AGE gets hit with this in its final episode with Zera Gins and his Vagan Gear, though his existence was hinted at earlier in the Kio arc. He shows up at the end of the final battle, when all non-mook Vagan pilots are dead, with his only motivation and lines being "destroy the Gundams." His own side calls him a soulless warrior and their strongest pilot, and it also is mentioned he's a clone of Lord Ezelcant. Then SID shows up and merges with Vagan Gear and he goes berserk causing both sides to ally to try and stop him. Then Kio destroys his Gear SID, and that's that (though Zera himself survives). As AGE was originally conceived as a licensed game by Level-5, Zera is a very direct transplant of the Giant Space Flea from Nowhere.
• In Naruto, Kaguya shows up out of nowhere (only being mentioned about forty chapters prior to her debut as being the mother of the Sage of the Six Paths and dead for centuries), is revealed to be responsible for all of the Uchiha turning evil, and gets sealed away after a relatively short fight. Her entire purpose is essentially to take out Madara because the author accidentally made him too strong. Despite being considerably stronger than him (she's the single most powerful being in the entire world) she has no true combat experience, so she's easier to defeat.
  • Later works of the franchise attempt to integrate her and her clan in the lore.
• Pokémon the Series: Diamond and Pearl:
  • The episode with the evil Togepi. It's never explained why the Togepi is evil or what her motivation is.
  • Tobias also qualifies, except his purpose, in writing terms, is simple: Eliminate Ash from the Sinnoh League with an overpowered team.
• Pretty Cure All Stars movies seem to have a tendency to use this trope gratuitously, due to lack of connection between individual Pretty Cure series. DX3 has the entity simply known as Black Hole. It's best described as The Heartless of every Pretty Cure villain, ever.
  • In HuGtto! Pretty Cure, while most of the villains get some buildup prior to any confrontation with the Cures, this does not apply to Mad Scientist Dr. Traum, who shows up, shoots one of his comrades, Daigan, and forces the Cures to fight him instead. Later, he does get some backstory revealing that he was the one who built Ruru to begin with.
• Despite being the Big Bad, Walpurgisnacht serves as at least a partial one in Puella Magi Madoka Magica. There's definitely some build-up to her, but she still takes a backseat to the Awful Truth behind the whole Magical Girl system and Homura's true nature. And the real villain Kyubey. In the end, her purpose in the plot is more to just show up, smash the city to pieces and either kill Madoka or cause her to turn into an even more powerful witch, forcing Homura to push her own personal Reset Button and try to do the fight over again while saving her. Hell, if it wasn't for Homura, no one would even expect a supremely powerful witch like Walpurgisnacht to just show up and start wrecking everyone's shit.
• Record of Ragnarok: The sixth round between the Buddha and Bishamonten/Zerofuku is already loaded with surprises from front to back, but when Zerofuku's on the ropes, the demon lord Hajun bursts out of him with no prior hints at his existence. The only elaboration is provided by characters who appear after him, and even they don't know everything.
• Kain, the villain of the Tenchi Muyo! movie "Tenchi In Love".
• Yu-Gi-Oh!:
  • Dark Marik is introduced very abruptly with no prior hint of his existence, in the middle of the Duelist manga' final arc, hijacks the story from his other half Marik, and proceeds to wreak uninhibited havoc as the new Arc Villain.
  • Grerimo from the Doma arc. Unlike other villains in the arc (and most in the series) he's a Flat Character with no backstory at all, with no explanation of why he works for Dartz. His entire purpose seems to be to introduce the viewers to the Orichalcos and present it as a threat.
  • The climax of Yu-Gi-Oh! The Dark Side of Dimensions has the Millennium Ring corrupting others, and bonding with Diva to create a reality-warping monster, but how it does so with Zorc and Yami Bakura gone is never explained.

Comic Books

• Batman: The Joker's backstory was introduced much, much later than the character and even in there, he outright stated that's probably false. Despite that, he's still managed to rack up a body count any villain worth their salt would be jealous of, and is the person regular (and super) criminals tell stories of to scare one another.
• Final Crisis: The Big Bad wasn't Darkseid. It was a multiversal vampire, the Dark Monitor Mandrakk. This means exactly what you think it does: he eats stories. Mind you this is explained and there is a lead up to it, but if you didn't read the Final Crisis: Superman Beyond tie-in, he seemed to come out of nowhere. Writer Grant Morrison did, however, intend for Superman Beyond to be an integral part of the story, and it is included in (most of) the trade editions.
• Godzilla: One comic had Big G be sent back to the time of the dinosaurs, where he was attacked by a giant dragon... thing that was there for some reason; he manages to just barely beat it before being returned to the present.
• Green Lantern: In Green Lantern: Rebirth, Hal Jordan's 90s Face–Heel Turn is explained as a result of his possession by Parallax, a heretofore unknown Fear Entity. Parallax has since become the Big Bad of a crossover event, one of the cornerstones of modern Green Lantern continuity, and was depicted as the giant floating CGI head of Clancy Brown in The Movie (for better or for worse). So while he is a Giant Space Flea from Nowhere, he's a beloved one.
• I, Vampire: The vampire that turns Lord Andrew Bennett, the titular character in the series. He turns up while Bennett is out riding, mesmerizes him, gives a little rant about hating Bennett's positive outlook on life, and wanting to show him the dark side and generally screw his life up, bites him, and then promptly gets staked by him. Then Andrew makes it home, filled with angst over his new condition, his wife agrees to be turned by him so that they can spend eternity together, she promptly turns evil, decides to take over the world, declares Andrew to be her enemy when he tries to talk her out of it and flies off to begin her campaign. And there's your central plot and background set, now on with the episodic story.
• Ms. Marvel: In Ms. Marvel (1977), Death-Bird is introduced just randomly attacking Ms. Marvel as she's doing something else, with only some hints as to the fact she's not even human. She later explains she had also been doing her own thing while working for A.I.M., saw Ms. Marvel and having heard of the superhero's own tussle with them figured "why not?"
• Preacher: The feral vampire hag that turned Cassidy. She appears biting his neck, gets shot by his brother, and falls back into the bog, never to be seen again.
• Severed: The comic has the unnamed Ambiguously Human salesman who goes by the name of Mr. Fisher (along with several others, all of them false). "Fisher" is a mysterious man who eats children to consume their dreams. No reason is ever given for this. "Fisher" claims to be hundreds of years old, and indeed, he never ages at any point in the comic. No backstory is ever given for him.
• Superman:
  • The Man of Steel #17 introduces Doomsday. He basically emerges from the bowels of the earth, squishes a bird, and then goes on a killing spree for no good reason. He's there just to kill Superman and kick off The Death of Superman multi-arc. Later stories revealed his origins.
  • The Unknown Supergirl introduces the Infinite Monster, an absolutely gigantic, invulnerable and unstoppable monster who drops out of a dimensional warp hole and goes on a rampage through the countryside for no apparent reason. It has no name, backstory or motivations and its sole reason to exist is to prove Supergirl can protect Earth in her cousin's absence and deal with dangerous threats on her own.

Fan Works

• The Pony POV Series has the first Big Bad Loneliness whose origins have never been explained and several potential ones are offered, but nothing concrete is ever given. She just shows up in Trixie's head as her Enemy Within. However, this was invoked by Word of God, as not giving her a set origin just makes her that much more terrifying both in-universe and out.
• In The Bridge an arc villain who shows up late into the story is a gumiho from Carrea, who's chased the kirin, Ki Seong, all the way to Equestria. There isn't any indication she's tied to the Big Bad or any of Grogar's students like King Sombra or Queen Chrysalis. She's just an obscure, dangerous entity hardly anypony knows of that shows up without warning. It's later revealed that her arrival was due to an out of control army of filly Destroyahs accidentally destroying the ward Ki Seong kept, breaking the seal keeping the Beautiful Terror at bay.
• Jaune Arc, Lord of Hunger has the Climax Boss of its first Story Arc: a terentatek.^note a Dark Side creature that resembles a rancor and preys on Force-sensitives. Up until then, the story had been about Jaune adjusting to life at Beacon Academy. The closest thing to an antagonist was the school bully Cardin. Midway through "Fear", the terentatek literally pops up out of the ground, scares off Cardin, and nearly kills Jaune while no-selling his strongest attack. Its existence had never been hinted at prior to this and it's the only villain who has no connection to the overarching Big Bad Ensemble. After the terentatek is killed, it is quickly forgotten and almost never mentioned again by the other characters.

Films — Animated

• The ending of the American Astro Boy movie. Just as the day is saved and everyone is celebrating, a giant sun-shaped alien with tentacles that shoots lasers out of its one giant eye attacks the town. No reason, no foreshadowing, someone just shouts "Alien!" and it's there. It's probably one last Shout-Out to the Artificial Sun from one of the earlier Astro Boy series.
• In the climax of The Fox and the Hound, when Amos Slade and Copper pursue Tod, an enormous bear appears out of nowhere, attacking and almost killing Slade and Copper. Tod, seeing Copper in danger, returns to fight the bear and save his pursuers. Eventually, he leads the bear over a log protruding over a waterfall. The log breaks under the bear's weight sending them both plummeting. Tod survives and the bear gets a Disney Villain Death.
• The Loc-Nar from Heavy Metal is never given a backstory, but it's the embodiment of Pure Evil that drives all the vignettes in the movie.
• In Lady and the Tramp there is a rat. It appears in a blink-and-you'll-miss-it scene right after the baby first appears, and is chased off by Lady. Then it reappears just ten minutes before the end of the film, tries to murder the baby, fights the Tramp one-on-one, wounding him and posthumously has the Tramp sent to the pound, where he is certain to be put down. He has no lines, has no known motive and is utterly evil throughout.
• In The LEGO Movie, the Duplo aliens.
  • This is true to the characters, but the audience knows that they're from a previously separated Lego bin in the real world.
  • The sequel reveals more about them, including their leaders, General Sweet Mayhem and Queen Wateva Wa‘Nabi.
• The Thief and the Cobbler: The Mighty One-Eye, and the entire race of monstrous One-eyed men he is the leader of (simply called the "One-Eyes") simply appear into the film without any kind of backstory. They want to conquer and destroy a Golden City, also without any explained motivation.

Films — Live-Action

• Many Werewolf Movies, such as An American Werewolf in London, Ginger Snaps, and Wolf (Mike Nichols), in which the protagonists are bitten and become werewolves, do not go into very much detail, if any at all, in explaining where the original werewolf came from—or the werewolf who made them, or who made that werewolf, and so on.
• Cloverfield: Unlike most giant monster movies, this one doesn't bother explaining the creature's origin, since the story is given from the perspective of an average citizen who, in any other Kaiju movie, would just be a background extra in the fleeing masses. Thus, no scenes with generals or scientists standing around providing exposition, it just shows up and rampages around New York City.
• In The Dark Knight The Joker has no Start of Darkness, no backstory (none that you'd believe, at any rate). He's just there at the start of the movie to wreak havoc, havoc, and more havoc, just 'cause, which actually serves to make him even scarier than he might be otherwise. As Alfred puts it: "Some men just want to watch the world burn."
• The Fifth Element introduces The Great Evil, an angry, black sphere that doesn't even have a proper name, let alone a motivation. But how would Bruce Willis find a cute thousand-year-old alien girl to nail without it?
• Frankenstein Conquers the World: The "International" cut climaxes in a fight between Frankenstein's Monster (in city-stomping kaiju form) and a giant octopus who suddenly shows up out of nowhere. Not only that, but it's a famous Japanese Mountain Lake Octopus, as most of the action takes place in the "Japanese Alps." Although it was filmed at the request of the American distributor, he apparently felt the end result was just too silly. The scene was cut from both the Japanese and American versions, but for reasons unknown, was kept in the "International" cut (English language, but for territories outside America.)
• The Leopold and Loeb-esque duo in Funny Games give various conflicting accounts of who they are and where they came from, but they're obviously all lies. They have no backstory and no reason to exist except to serve as villains for the movie you're so sadistically viewing, You Bastard!.
• Monster X/Keizer Ghidorah from Godzilla: Final Wars. He just appears out of nowhere (though it's implied he was inside the meteor "Gorath" that was heading to Earth), fights Godzilla to a draw, transforms into his more-powerful form, nearly curb-stomps Godzilla to death, and then is ultimately defeated after Godzilla gets a power boost.
• Michael Myers in Halloween (1978) had no motive or backstory; he was just born evil, killed his sister when he was six years old, spent the next fifteen years in a psych ward, and finally broke out and returned to his hometown to kill again. Dr. Loomis, the psychiatrist who spent years trying and failing to reach him before simply giving up, describes him as an emotionless sociopath and evil incarnate. Later films, however, roll back this part of his character, giving him family relations to the series' protagonists and eventually revealing that he is being compelled to kill by an ancient Celtic curse, though Halloween (2018) jettisons them all and returns to the first film's characterization.
  Dr. Loomis: I met him fifteen years ago. I was told there was nothing left. No reason, no conscience, no understanding in even the most rudimentary sense of life or death, of good or evil, right or wrong. I met this six-year-old child with this blank, pale, emotionless face, and... the blackest eyes. The Devil's eyes. I spent eight years trying to reach him, and then another seven trying to keep him locked up, because I realized that what was living behind that boy's eyes was purely and simply... evil.
• The killer in HellBent is given no origin or motivation, never has his name or actual appearance revealed and isn't even mentioned in the credits. Also, making a literal example of the trope, he's dressed as the devil.
• The Hitcher: When the police arrest John Ryder, they can't match his fingerprints to any existing criminals, nobody knows anything about him, and even his name is undoubtedly an alias (in the remake, it was stolen from one of his victims). It's as if the desert just spat out Death in human form.
• The shark from Jaws has no reason to be so big, eat people, and sink boats. But thank goodness it is and does because Roy Scheider and Richard Dreyfuss are a match made in heaven. Of course, how much motivation does a shark need? Occasionally animals realize humans are pretty easy to kill and start eating them, they tend to keep doing so until they die. It helps that for most of the movie, the townspeople make little to no effort to avoid the maneating shark they know is sticking around the beach. The attempt to give it a more detailed backstory and motivation in the sequels is the Trope Namer for Voodoo Shark.
• Krull: The Beast appears from outer space, invades the world and randomly crashes wedding parties all in the name of being bad. While the backstory of the Cyclops indicates that the Beast has done this sort of thing on other worlds before, there's otherwise no backstory for the Beast itself explaining where it came from and why it decided to go about invading worlds.
• Lord of Illusions: The Big Bad Nix is an Evil Sorcerer with immense eldritch powers, which he states he will soon use to kill all of humanity. Where he came from or how he got his powers is never explored. When someone questions what he is, he simply replies "a man who wanted to be a god... then changed his mind".
• In the horror film The Monster (2016) the titular creature appears from the woods, kills several people and terrorizes a mother and daughter, eventually killing the mother before in turn being killed by the daughter. Neither the characters in the film nor the audience receives any insight into why it does what it does, where it came from, or even what the hell it is. It's just there.
• Discussed in Nope, with OJ wondering if there's such a thing as a "bad" miracle. The UFO, Jean Jacket, is ultimately revealed to be an invoked example: its origin — if it could conceivably have any — isn't explained, it literally comes down from the sky, and it has nothing comprehensible as a "motive" other than hunger and pure animal stimulus-response behavior.
• The murderous robber dressed like Santa Claus from the beginning of Silent Night, Deadly Night.
• The Whale Probe in Star Trek IV: The Voyage Home is never given any backstory or origin. It's the quintessential Big Dumb Object that exists to make Jim Kirk's court-martial more of a hero's welcome. (The probe was eventually given a back story in the book ''Probe''.) Justified in Spock's exact line, "Only human arrogance would assume the message 'must be meant for Man'." One might imagine it was quite chatty with the cetacean life it was sent to contact.^note According to the creators, having their conversation with the whales at the end translated was considered and rejected. Given the brevity of said conversation, it didn't go well.
• The Big Bad in Who Framed Roger Rabbit becomes this with The Reveal that he's actually the toon who killed Eddie Valiant's brother. He remains an Unseen Evil behind his Human Disguise, and we have no idea how he got to the position he currently occupies under his assumed identity.

Literature

• "The One" from Animorphs. It is a literary Giant Space Flea from Nowhere, introduced in the very last chapter of the very last book after the Yeerks are defeated. There is no explanation of where it came from or what it wants, it merely becomes the remaining Yeerks' new god, assimilates Ax, shapeshifts to a bunch of random things to freak the heroes out and gets its spaceship rammed. K. A. Applegate's comments seem to indicate that she just wanted the good guys to get screwed by a new war and created a Diabolus ex Machina to let them go out in a blaze of glory.
  • Whatever it was that sent Jake to a Bad Future, as some kind of test, in The Familiar, the definitive Bizarro Episode of the series. Some fans wanted it and the One to be the same thing, if only to make each have some overall relevance, but Word of God shot the idea down.
• Simona Ahrnstedt gives us Carl-Jan Rosenschiöld in her debut novel Överenskommelser. To be fair, this novel has three villains (because one creep obviously wasn't enough), whose misogyny is disgusting even by the standards of the time in which they live (the 1880s). But the other two are at least given backstories, which can somewhat explain how they ended up being that way. But with Rosenschiöld, the guy is just there to be evil! He's a sadistic serial abuser of women, who only wishes to marry female protagonist Beatrice (who's like forty years younger than him) because he wants a virgin. We do get to see him die, but not until after he has brutally raped and almost killed Beatrice on their wedding night. Only after his death are we given some backstory: Rosenschiöld has murdered one previous wife and driven another previous wife into suicide. But we're never told how he could become so evil.
• With the exceptions of Blaine the Mono and Andy the Messenger Robot (Many Other Functions!), pretty much every robot in The Dark Tower. They show up, kill, maim, or psionically alter someone, then are either destroyed or returned to hibernation.
• The Silmarillion by J. R. R. Tolkien has Ungoliant; she is said to have "descended from the Outer Darkness, maybe, that lies in Eä beyond the walls of the World." She destroys the Two Trees and almost eats Morgoth. After breeding with lesser spiders, she just... wandered off.
  "Some have said that she ended long ago, when in her uttermost famine she devoured herself at last."
  • The History of Middle-earth gives more details, with Ungoliant originally written as an Eldritch Abomination 'personification of primeval night' before the world was made, and later this being changed to her being a Maia and former disciple of Morgoth who grew strong enough to equal him in his long years of imprisonment. Also, Ungoliant was originally planned to re-enter the story — Eärendil slew her in one of his adventures on the way to Valinor. It's likely this would have ended up in The Silmarillion if Tolkien had ever finished that part of the story.
• In The Silver Chair (the fourth installment published in The Chronicles of Narnia, and the sixth in terms of In-Universe chronology), Tolkien's pal C. S. Lewis gave us the Green Lady. We know she's a "Northern Witch" who might be somehow connected with the infamous White Witch, but that's about it.
• In Tuck Everlasting, the Big Bad is a genteel, polite person known only as "the man in the yellow suit". He does provide some backstory for his quest — as a child, his parents sheltered a family that told tales of the mother's former husband and his own kin, who never aged a day — and has clear goals in selling the magical spring water that generates said immortality (apparently choosing to ignore the horrific implications of what will happen when the secret gets out), but other than that, he's a blank: no name, no past, no relatives, no presence...nothing. Author Natalie Babbitt encouraged this characterization in an interview, and even explained that she deliberately avoided giving him a red or black suit for fear of people interpreting the man as Louis Cypher or The Grim Reaper; she elaborated that she put him in yellow to create a natural cadence for the repeated phrase "the man in the yellow suit".
• In the Warrior Cats series, the Big Bad Tigerstar had nine lives at the beginning of the (then) final book, The Darkest Hour. In order to avoid making him seem like a pathetic weakling, the authors had a random cat called Scourge show up, kill Tigerstar all nine times, kill the protagonist, Firestar, and take over the Clans. And then Scourge died.
• In Journey to the West, nearly all of the foes encountered are Taoists or animals spirits who overheard celestial secrets. Baigujing (Lady White Bone) doesn't have an origin revealed, only being described as a "Skeleton Spirit" yet is considered the most evil.

Live-Action TV

• In Breaking Bad, the Aryan Brotherhood, though more normal than other examples, serves this purpose. They come out in the final season with not much build-up, being Neo-Nazis is good enough to explain why they are bad guys and are so good at what they do (mostly killing and breaking people) that they kill any other conflicts the series had that is not them.
• In Buffy the Vampire Slayer, the First Evil is the Cosmic Horror personification of evil. It wants to make people hurt and sin because, well, it's evil. There's not really much else to say about it, aside from what's on the tin.
• The enemy from the Doctor Who episode "Midnight" — we never see its true form, or learn its name. It just appears out of nowhere, possesses Sky, places the Doctor and everyone with him in grave danger, and is eventually defeated — but certainly not killed — by a random bystander, as it has incapacitated the Doctor. Considering how often the Doctor exhibits an encyclopedic knowledge of... everything... throughout his adventures, many count the episode as one of the eeriest in all of Doctor Who, to the point of That One Case.
• After being built up as the real existential threat to the warring Seven Kingdoms throughout Game of Thrones, the Night King, White Walkers, and their Army of the Dead were defeated in the last season with little explanation of what their motives were and how they came to be.
• Kamen Rider:
  • Kamen Rider Kiva infamously ends with the main characters all attending a wedding, only for a time-traveler to burst in and warn them about an invasion of alien vampires from the future that's about to take place. Here We Go Again! ensues.
  • Kamen Rider Decade uses this type of final boss in both movies, in both cases recycling a villain from the Showa era to come out of nowhere right near the end of the movie. In Kamen Rider Decade: All Riders vs. Dai-Shocker, there's King Dark, the Big Bad of Kamen Rider X, who only rises after all the other villains are killed. It was never hinted anywhere in the movie that he would even appear at all. Since there is already a personification of the Great Leader, recurring Bigger Bad of the Showa era in the eponymous Decade, it means that there are two Great Leaders running amuck. He was probably just included to give an excuse to use the giant Kamen Rider J (the movie did say All Riders). Kamen Riderx Kamen Rider W Decade Movie War 2010 has Doras show up after dealing with both Tsukasa and Super Shocker, with only slightly more foreshadowing.
  • Kamen Rider Zi-O, which consists largely of stories homaging the previous nineteen Heisei era shows, makes sure to include an alien villain who appears without explanation during the Kiva arc. No attempt is ever made to explain him or what he's doing in this time travel-based show, and after two short battles, he leaves just as quickly as he arrived.
• The creators of Merlin (2008) promised in an interview that the end of season four would end with an intriguing Cliffhanger in which a previously seen "evil" character would reappear. Most fans bet their money on Mordred. However, it turned out to be something completely random. In an early season four episode, Merlin discovers a dragon's egg, hatches it, and calls the baby dragon Aithusa, said to be a symbol of the forthcoming Golden Age of Camelot. The audience was given absolutely no reason to believe that Aithusa was anything but a harmless baby dragon, who is not seen or mentioned until the end of season four, where it appears in the forest to heal an injured Morgana for no apparent reason and fly off again.
• Star Trek: The Next Generation's pilot episode introduces "Q", a god-like entity that begins harassing the crew seemingly for the sake of it. He simply appears on the bridge and creates unnecessary drama. While he eventually becomes a beloved character by the end of the series, he was unimportant to the plot of the pilot. Word of God says that the pilot was originally going to be one episode, but Executive Meddling forced it to become a two-part episode. So Q was made up to fill the extra hour. (It ended up paying off incredibly well for them, as Q is generally considered the best part of the pilot and became one of the most successful Breakout Characters of all time.)
• Star Trek: The Original Series had the Doomsday Machine from the episode of the same name, a giant weapon that flies through space eating everything it comes in contact with, up to and including entire planets. Spock believes it came from another galaxy, and Kirk theorizes it may have been built as a form of Mutually Assured Destruction in a war, intended as a bluff or deterrent but ultimately used, however the true origins and purpose of the machine are never revealed. (The Expanded Universe novel "Vendetta" by Peter David eventually revealed that it was designed to destroy the Borg.)
• In Stephen King's mini-series Storm of the Century, little is revealed of villain Andre Linoge; he simply shows up, beats an old woman to death, and proceeds to terrorize a small island town trapped in a snowstorm until they give him what he wants.
• True Blood:
  • The Big Bad of the second season was Maryann, a maenad: a follower of the Greek god Dionysus whose fervent devotion somehow turned her into a demigoddess. In a show whose main focus was on vampires while other supernatural beings still had well-established backstories and communities of their own, Maryann was the only maenad to ever appear and her storyline is largely confined to season 2, making her feel very Monster of the Week compared to later antagonists, especially since unlike the season 1 big bad, serial killer Rene, Maryann is never mentioned again for the rest of the series.
  • Zig-zagged with the Yakonomo Corporation. On one hand, their invention of the synthetic blood beverage Tru Blood served as the basis of the entire show, as it allowed vampires to "come out of the coffin" and live openly without having to feed on humans. But on the other hand, the actual company was never given any focus until close to the end of season 6, and it wasn't until the seventh and final season that they were central to the plot. That's when it was revealed out of nowhere that they had been controlling vampire society long before they invented Tru Blood, with Yakuza as their enforcers.
  • The Yakuza themselves play this trope straight since they neither appeared nor had any mention at all until the final season. We first meet them in a flashback to 1986 where it's revealed that they were the ones who sent Eric and Pam to Shreveport, Louisiana as punishment for their disrespect. The leader of this particular cell, Hiroki, reappears in the present day yet hasn't aged in 28 years, but it's not stated that he's anything other than a normal human. Their appearance in the show is immortalized by recurring villain Sarah Newlin calling her mother and frantically yelling, "Mom! The Yakuza are trying to kill me!"
• One episode of Ultraman Ace had the hero already in trouble fighting two kaiju at the same time, Doragoris and Alien Metron Jr. Then a third kaiju, Muruchi, suddenly shows up, resulting in a Cliffhanger (it's the first episode in a two-parter) where Ace finds itself surrounded by three enemies, resulting in a serious beatdown in their favor.

Myths & Religion

• Greek Mythology:
  • In Hesiod's Theogony—an early Trope Codifier of Greek Mythology—Typhon is one of these. He shows up out of nowhere to wreak havoc after the Olympians win their war against the Titans and Giants. Zeus defeats him and the world is finally at peace. Some later retellings either edit this bit out for being too random or write the battle as a more grandiose affair.
  • Various tellings of the story change a bit of that; Typhon is described as a child of Gaia and Tartarus, set against Zeus by Gaia when she believed his rule wouldn't be much better than his father's. The battle was less a curbstomp, with Typhon having the edge early on (ripping out Zeus' tendons), before being defeated by having a mountain dropped on him.
• Surtr in Norse Mythology. At Ragnarok, he will suddenly show up, kill Freyr, and then set the entire universe on fire, killing all but a few gods and leaving room for another world to appear. Beyond that he has no backstory or motive, except that he's a fire giant from Múspellheim, the Realm of the Fire Giants.

Professional Wrestling

• WWE has done this twice with Underfaker and Fake Kane. They showed up, confused people about their relationship to The Undertaker and Kane, were eventually defeated by the real thing, and then vanished.
• Boogeyman in Ohio Valley Wrestling. However, after about three appearances, officials began to anticipate his coming and took measures to stop him, even contacted law enforcement. Nothing they did ever worked and he would quickly depart into ether almost as quickly as he arose. Oh, and he was a "heroic" version, as the crowd quickly took a liking to him, to the point he was cheered when he interrupted handicap match between the already injured Alexis Laree against Beth Phoenix and Shelly Martinez and attacked Laree. So Boogeyman turned to mainly beating up wrestlers the audience did not like, making him even more popular. Unlike most examples, Boogeyman did have an explained though nonsensical motivation, he wanted to be a professional wrestler. He was eventually given a Backstory on WWE Smackdown too. (He was supposed to be a star of a new show on UPN, but "something happened on the set." This was eventually abandoned.)
• Kevin Sullivan and his army attacking Ring Warriors Grand Champion Bruce Santee. Turns out they did so exactly because people thought they were obsolete.
• CHIKARA simply announced that Wani would be on Juan Francisco De Coronado's Squad for the Torneo Cibernetico at the 2015 Season Finale Top Banana and never did come up with a character or backstory for him.
• WWE 1992: Doink the Clown just started showing up in the crowd, with no buildup, no background, no explanation, no clue as to his motivations.
  • Commentator Vince McMahon outright Lampshaded this when Doink was making balloon animals in the entranceway during the Rick Martel vs. Tatanka match at Survivor Series 92, asking, "What is he doing here?"

Video Games

• On your way through the abandoned subway towards the end of Beneath a Steel Sky, you come across a crevice that holds a tentacled, presumably gigantic monster that will kill you unless you take the right precautions. It has no discernable connection to the main threat in the game, and there is no indication as to what it is or where it came from.
• At the end of the Wasteland questline in Billy vs. SNAKEMAN, a villain appears, explains that the odd sickness you've been suffering from is caused by his genjutsu/poisons/cloning technique (it's a different villain and trick depending on which primary bloodline you have), that he's been manipulating you from the very start, but has decided that you've outlived your usefulness. Then you beat him up and force him to join your team. At no point was there even a hint that the questline had a villain - you were just scavenging for shinies and picking up cool allies.
• Chrono Trigger: Lavos. It falls from the sky in the distant past, causing the equivalent of the Cretaceous extinction. Millions of years nourishing out of the planet's core later, it (after an initial firestorm) emerges and proceeds to wreck the place. And it was not the first time: it had done it before when the premier magicians in the world tried to use it for fuel.
  • And then there's Chrono Cross, where the final boss is yet again Lavos, who exists in a non-reality unplace of infinite nothing never where the countless versions of people are erased over. Oh, and then it decides to eat all of time because of Crono's actions in the first game.
• The titular mothership of the Fallout 3 add-on Mothership Zeta deserves mention. Without any previous foreshadowing, the Lone Wanderer is abducted by the aliens and must spend the next several hours (days, in game time) fighting his way through the mothership just to get home. At which point, the entire experience is never mentioned again. What exactly the aliens were doing with all the people they've been abducting over the past thousand years or so is left vague at best.
• Jenova in Final Fantasy VII appears from the sky two thousand years ago and murders most of the planet's population. After being dismembered and frozen she is revived in modern times and starts all over again. No motive or origin is ever given.
  • Sephiroth hints that the cycle of parasitic destruction is Jenova's true purpose: it crashes into a planet, sucks out the Lifestream energy, and then leaves to crash into another planet. However, it's very vague at best. Sephiroth's goals may be his own, rather than an extension of Jenova's. However, in Advent Children Sephiroth does explicitly claim that he shall sail the Cosmos to find another planet to find a shining future, like his mother once did. So maybe he really is following Jenova's Goal after all. As usual of the trope, the explanation comes 10 years after the game and from a different writing team.
  • In Dirge of Cerberus, Omega Weapon's purpose is similar to Jenova's: to take the life energy of the planet and find a new planet when planet-shattering catastrophes happen.
• Final Fantasy IX. Has Necron, the last boss of the game. It's basically the god of death and is roused by Kuja's suicidal actions and attempts to destroy all life in the universe due to believing that living things are death seekers by nature. It suddenly shows up at the end of the game despite having never been mentioned beforehand, is fought by the party and then departs. No further elaboration is made on Necron and its character remains somewhat mysterious.
• From the Five Nights at Freddy's games we have Shadow Bonnie and Shadow Freddy. Appearing as Easter eggs in the second game, they appear as shadowy copies of Bonnie and Freddy which crash the game if you stare at them for too long. Unlike most other animatronics, which eventually get some kind of backstory, these two never get any sort of explanation; they only reappear once in the main story, in the Atari-style minigames of the third game, and that reappearance just raises more questions than answers.
• The titular villain from Jimmy and the Pulsating Mass is one of these: for some reason, it just showed up one day, dead set on killing Jimmy. Everything that comes out of its mouth(s) is a long tirade about how much it hates Jimmy and how gruesome his death will be. Every other antagonistic force in-game has deeper motives, including the ones that it corrupted. Which makes perfect sense when its true nature becomes apparent.
• The Aurum in Kid Icarus: Uprising are explicitly stated to "come from and return to nothing". They are a strange robotic alien Hive Mind that come from nowhere and become the main threat for Chapters 15-17, and force Palutena, Hades, and Viridi to form an Enemy Mine.
• FromSoftware really likes this trope in their games, with cryptic plots, indirect storytelling, and complicated questlines requiring players to pay attention. Even then, they really like throwing an unexpected opponent out of left field:
  • Bloodborne: The Moon Presence created the Hunter's dream and empowered the hunters so that they could stand against the Beasts and the Nightmare. Despite its heavy influence on the plot, until you kill Gehrman, the only hint of its existence is in the description of one of the umbilical cords and a note in the Lecture Hall, and it pretty much comes out of nowhere during the final cutscene to either kill or enslave you.
• In the Legend of Skyloft told in The Legend of Zelda: Skyward Sword's introductory sequence, it is told that one day, demons led by their king Demise suddenly rose from the ground out of nowhere and started killing everyone to get the Triforce, forcing the Goddess Hylia to raise a human settlement above the clouds to keep them safe. The conflict during the game proper is caused by the remnants of the demonic forces, but the game's plot doesn't touch on how Demise came to be.
• The Dark Star in Mario & Luigi: Bowser's Inside Story—someone accidentally dug it up one day, realized that whatever the hell it was, it was bad news, and immediately called upon the royal family to seal it away. Fawful thinks that it might be useful. He is dead wrong.
  • Yoshi's New Island: After beating Baby Bowser, the adult Bowser shows up out of nowhere and fights you.
• Bad Girl in No More Heroes, the 2nd Ranked Assassin. Most Bosses have some background, history (some tragic, making them a little sympathetic), and/or motivation explaining why they're killers, but Bad Girl has nothing but rage, hatred, and insanity. No mention of friends or family, her past, any Freudian Excuse, no motivation for what she does other than For the Evulz. Travis takes note of it, and it's what disgusts him about her the most. No More Heroes: Travis Strikes Again introduced Bad Man, Bad Girl's father, who's out for revenge against Travis for Bad Girl's death, and it's revealed in the DLC that Gresco, Bad Man's former employer, tortured and brainwashed Bad Girl to awaken the killing potential that her father shared.
• Sulphur from Phantom Brave is this monstrous demon thingy that wants to kill everyone. Nobody knows why, nobody asks why.
• In Resident Evil 3: Nemesis, there's well, Nemesis itself. Its specific origins have never been explained in any canon medium, which is weird because just about every other creature Umbrella has ever thrown at Jill and the other heroes has some kind of documentation or a plot point revealing what it used to be or how it was created. The closest one there is to an explanation is that it's a Tyrant imbued with an NE-T parasite developed by Umbrella's French division. Interestingly, Nemesis does get an origin story in the related film series.
• Thanatos from Secret of Mana, despite being the most active threat of the Empire and becoming the main antagonist, before the Mana Beast gets revived. Thanatos is looking for a body to take over, and he has powers from the Underworld Mavolia... that's really all the player ever finds out. Majority of his actions under the Empire were not required in his goal of taking over Dyluck's body. He just seems to cause chaos For the Evulz.
• Sly Cooper series.
  • It's known that Clockwerk was jealous of the Coopers for their superior thieving reputation and that he turned himself into a robot to gain immortality so he could continue to hunt them for centuries. However, it is not known why he became a thief in the first place, nor does he have any backstory prior to becoming a thief (for example, if he had a family or a Freudian Excuse). It is also unclear how he was able to turn himself into a robot when he was born thousands of years before the concept of robotics even began, or if Clockwerk is even his real name.
  • The Mask of Dark Earth from the third game also qualifies as it was never explained where it came from, how old it is, or what created it.
• Sonic Frontiers gives us The End. Unlike Chaos or Dark Gaia before it, there is no explanation for it or what it wants, aside from destruction; What it is, where it came from, why it wants to destroy the Koco so badly, it's relationships with Cyberspace or the Chaos Emeralds, why it appears as a living planet, nothing. All we know is that it followed the Koco to Sonic's planet centuries ago after forcing them off their own planet, and manipulated Sonic into destroying the Titans so it can be free to destroy everything once again.
• Super Smash Bros. Ultimate takes this to its logical conclusion with Galeem, the main antagonist for the World of Light adventure mode. It arrived out of nowhere one day, was pushed into a corner by the many heroes and villains, proceeded to unleash an ultimate attack that wrecked everything in the multiverse (except for Kirby, who barely escaped by having his warp star go into hyperspeed), then remolded it. Dharkon also arrives suddenly later on, with its only motivation being that it can't stand Galeem at all, and has also remolded a part of the multiverse.
• Tales of Vesperia has Zagi. Zagi has no backstory, no motive, no discernible allegiances (he doesn't even show concern or loyalty to the other members of Leviathan's Claw), no specific goal beyond killing people For the Evulz (and getting off to fighting Yuri) and no concrete connection to any of the characters. He just turns up at random points, even when it makes no sense for him to do so, to antagonize the party. This, however, is exactly what frustrates Yuri so much.
• Trials of Mana gives little information for half of its villains.
  • The Dragon Lord may be the Big Bad for Angela and Duran, but very little is known about him. He fought Hero King Richard and killed Duran's father, the Golden Knight Loki, and considers himself to be a god. But his origin — simply being a megalomaniac dragon or perhaps a demon that attained more power — his shrouded in mystery. Out of the three Final Bosses in the game, his motivations are the weakest.
  • Belladonna killed Eagle and framed Hawkeye for his death, placed a cursed necklace onto Jessica to ensure that Hawk wouldn't be able to reveal the truth unless he's willing to risk her death, and was the one to manipulate the Nevarl Thieves Guild to invade Citadel Laurent. She can turn into a cat demon for her boss fight, but if she was originally a demon or a human that became demonic is unclear. The most known about her is her devotion and love for the Dark Majesty.
  • All that's known about Goremand is that he works for the Masked Mage, he was the one to kidnap Heath, and made Karl attack Kevin.
  • Nothing is really revealed about Malocchio. The closest to giving depth to him is Belladonna's monologue if Hawkeye or Riesz are not the main protagonists. Belladonna didn't want to go through with the plan of merging the world with Mavolia if her beloved Dark Majesty wasn't around, but Malocchio seemed willing to go through with it and is implied to have planned to rule it himself, so his loyalty for Dark Majesty is likely not as deep as Belladonna's.
• Flowey from Undertale is a subversion. Every other antagonistic character in the story has their own motivations that ultimately render them sympathetic, but this guy seems to be the sole exception: he tries to kill you in the first five minutes purely for his own amusement and at the end of the Neutral route he kills Asgore in cold blood, absorbs the human SOULs, and transforms the world into a terrifying hell-dimension in which he intends to torture you forever. Without him, the plot of the Neutral route would be essentially unchanged, and he only shows up in the final moments to provide you with a surrealistic Final Boss battle. The Pacifist and Genocide routes, however, give him an excellent Freudian Excuse for his appalling behavior and integrates his story seamlessly with the other monsters': he's the reincarnated form of Asriel Dreemurr, trapped in his form without the ability to love. He's reset so many times that everyone's actions are fully predictable, and he's resorted to killing in an attempt to feel something. Should you take the Pacifist route, he briefly regains his SOUL and displays remorse for his actions, seeking forgiveness from Frisk. Also, if you backtrack at certain points, you can see him following you throughout your adventure, and he’ll even leave a message for you at one point.

Web Comics

• Parodied in Adventurers! — possibly even a direct parody of Necron — when, after finally defeating the distinctly non-Space-Flea Final Boss and fleeing his collapsing lair, the party is suddenly faced with Necrevil, "the embodiment of evil itself!"... and they just keep running.
  • Eternion on his first appearance is also an abrupt Giant Space Flea from Nowhere, but he becomes a recurring villain and arguably has more of an impact on the plot than the Big Bad himself.
  • While he's decidedly more human than most examples of this trope, this guy still qualifies by dint of location.
• Morthol Dryax in Problem Sleuth, who pops up, is soundly defeated 22 pages later, and isn't mentioned anywhere else. Fluthlu counts as one too, and appears shortly after beating Morthol Dryax. It's also never mentioned again in the series, apart from a Mythology Gag or two in Homestuck.
• Homestuck kind of plays with this trope. The nonlinear nature of the story means that for the reader it doesn't come out of nowhere, but from the perspective of most of the trolls Bec Noir was this, suddenly appearing shortly after they defeated their Final Boss.
• The Rogue Canadian Scientists in The Inexplicable Adventures of Bob! were introduced this way, as a joke threat from nowhere that was defeated in just a few panels. They return as a more serious threat about four years later.
• Awful Hospital: The Dolphin. There are a few references◊ to it before it finally appears, but it's given no explanation whatsoever. Fans of the author's previous work and/or social media may be aware that he has expressed a strong dislike of dolphins for various reasons, but other than that, it's entirely this trope.

Western Animation

• Avatar: The Last Airbender has the silent assassin nicknamed Combustion Man. All we know about his backstory is that he blew off An Arm and a Leg in the process of honing his specialised firebending technique. We do know his reasoning for attacking the Gaang- Prince Zuko hired him to do so back when he was still working for the Fire Nation, but even Zuko offering thrice the payment to stop won’t calm him down.
• In Courage the Cowardly Dog, this trope is somewhat common, as some monsters and other threats normally appear in the farmhouse without any explicit reason.
• The DuckTales (1987) special Super Duck Tales starts out with four relatively down-to-earth episodes, where we're introduced to Fenton Crackshell and find out how he became Scrooge McDuck's accountant and the super hero Gizmoduck. And the villains during those four episodes are the Beagles, who are just normal criminals and appear in many other episodes on the show outside this arc... But in the fifth episode, "Money to Burn", everything is changed when some alien robots randomly appear on the scene to steal Scrooge's money bin. Granted, the robots have a stated motive (they need the metal from the coins to make new robots) but they still come out of nowhere, just to make Scrooge, Fenton/Gizmoduck and Launchpad suddenly go on an adventure in space, almost kill the heroes to make axle grease and be destroyed by Fenton/Gizmoduck.
• Spoofed in the Futurama episode "Time Keeps on Slippin'", when the Harlem Globetrotters (who in the 31st century are an entirely separate species from mankind) show up randomly one day and admit that now, for no reason, they are challenging humanity to a game of basketball, with no stakes and no threat... beyond the shame of defeat. This is because executives were asking the writers to have stories with more stakes.
• Dr. Claw in Inspector Gadget is a faceless enemy that is constantly plotting against the titular hero. His organization seems to have no other purpose than to "Get Gadget". Claw's face was not even revealed until nearly twenty years after the show's run ended. Except on a toy.
• Battle Beast was portrayed this way in the first season of Invincible (2021). While the comic gives him a proper introduction and eventually expands on his character, his first appearance in the show makes him seem like a Giant Space Cat from Nowhere as he's teleported in alongside a few lower-tier supervillains by the Villain of the Week, beats three of the Earth's mightiest superheroes half to death with minimal effort, then promptly leaves.
• In the Backstory of Equestria as told in "Hearth's Warming Eve" in My Little Pony: Friendship Is Magic, the Windigos were these. They were said to be creatures that feed on The Power of Hate, but they came out of nowhere and had absolutely no explanation for what they planned to do with the winter they were causing, but they forced the three races of pony to band together, since they were able to create a beacon of friendship-powered fire to burn them away.
• The Powerpuff Girls (1998):
  • Although not many of the villains have elaborate origins, the nanobots in "Nano of the North" seem especially inexplicable. They're a swarm of microscopic robots that come out of a cloud that forms over Townsville but nothing else surrounding it, start devouring all the carbon to make more of themselves and demonstrate some kind of group intelligence in the way the cloud changed to focus the forces onto the Powerpuff Girls. Although they're all destroyed by the end of the episode, no clue is given as to their origin or why they were targeting Townsville specifically, and indeed no one even asks.
  • The evil alien force from "Forced Kin" suddenly comes from space to conquer Earth with no explanation, and turns out to be so strong he forces Mojo Jojo and the Powerpuff Girls to work together.
• In Regular Show, Mordecai and Rigby are vying for a chair and bet on it in rock-paper-scissors. After being stuck in a tie for 100 times, a monster from out of nowhere comes to eat the chair, they were able to make it go away by breaking the tie. This is actually the formula many of their episodes run by. The characters start off doing something fairly mundane, like going on a date or buying fast food, then all of a sudden, the fantastic enemy of the week pops up to give the characters a new conflict.
• The Rise of the Teenage Mutant Ninja Turtles episode "Mrs. Cuddles" has the titular Evil Doll, which April O'Neil borrowed from her kiddie show temp job for a prank. She's alive, feeds on screams to grow stronger, and can only be kept at bay with laughter, so the Turtles and their allies end up doing the latter to defeat and stuff her back into her chest. Not only is it not explained how or why she came about, she seemingly doesn't have anything to do with the Yokai or the Foot Clan (who also have mystic powers).
• Steven Universe:
  • At the show's start, each Monster of the Week has zero context with the story, unless Steven decides that it's cool enough to keep around juuuust long enough to blow up in his face. However, revelations from later episodes slowly but surely subvert the trope; the Red Eye, for instance, was a probe sent by the Gem Homeworld, and the Centipeetle is one of many corrupted, insane Gems left behind after the Rebellion.
  • White Diamond, the ruler and apparent creator of the other Diamonds and by extension all Gemkind, is a downplayed example. She has a defined personality and a familial relationship with the other Diamonds, while Homeworld's empire (in particular its extreme conformity) are implied to be extensions of her narcissism. That said, her actual origins are never addressed at all.
• Teen Titans
  • Slade's backstory and motives were never revealed, despite him being the Big Bad for the first two seasons, the Dragon with an Agenda in the fourth, and a major presence throughout the series. The heroes, especially Robin, speculate as to who he is, but nothing concrete is ever reached.
  • Red X was originally created as a persona by Robin to get close to Slade back in Season 1 and abandoned when that plan fell through... Which is why Red X's sudden return as a separate entity from Robin in Season 3 came as a major shock with no immediate explanation or origin for his appearance. It's quickly surmised that someone had stolen and donned the Red X suit to do whatever he wants, but similarly to Slade, we end up with no information on who that someone is and no information on his backstory. The second Red X just appears out of nowhere and makes trouble for everyone. Beast Boy tries to speculate,^note He thinks it's Jason Todd but Raven says it could be anyone and no one else really gives it any thought.
  • The Monsters of the Week from the episodes "Stranded" (an alien monster attacking a space station) and "Things Change" (a material-copying robot attacking the city) both come out of nowhere and though the characters wonder out loud what they are, we are never given even a vague explanation.
• ThunderCats: In the series finale, after Lion-O fights an epic final battle against his Arch-Enemy Mumm-Ra, the Ancient Spirits of Evil randomly throw "their champion," a giant warrior named Pyron, at Lion-O just to fill up the last couple of minutes or so of the episode.
• Transformers: The Movie features Big Bad Unicron who drifts out of the vastness of space and starts eating things and making bargains with Decepticons. Though he appeared from the vacuum, he certainly didn't vanish afterward though. Later episodes and adaptations would elaborate more on his backstory and motivations, but the movie itself doesn't make him anything other than being the biggest threat the Autobots and Decepticons have ever faced.
  • Further incarnations were slightly more careful with this. Armada hinted he was in the background for a while, Energon followed as a sequel, and Transformers: Prime dropped hints about him every now and then before he appeared for real.
  • Played straight again in the live-action film series, which reveals him to be the core of Earth with no explanation how or why (and none forthcoming, after the decision to reboot the movie universe).
• The version of Apocalypse in X-Men: The Animated Series. He is a invincbile immortal villain who seeks to bring about the end of the world so he can rebuild in his own image. But since the character's origin wasn't revealed in the comics, the show never explained his backstory either. The most that is revealed about him is that he's implied to be the personificaiton of evil itself. Subverted in the show's comic book continuation, which reveals him to be Good All Along and that he was testing the X-Men for something worse.

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