History Main / MoriartyEffect

[[quoteright:201:http://static.tvtropes.org/pmwiki/pub/images/Pd_moriarty_by_Sidney_Paget_2898.gif]]
[[caption-width-right:209:''*sniff*'' I was only ever in one story, you know ''*sniff*''.]]

Not every hero has an archvillain... initially. Sometimes, though, a villain will be introduced who ends up being a BreakoutCharacter in his/her own right, and thus a [[MonsterOfTheWeek Villain of the Week]] becomes ''the'' villain of the ''series''.

This can be caused by many things, from ExecutiveMeddling, to WriterRevolt, to unbridled fan response to the character, to the writers being blown away by the performance of the actor who shows up to play the role.

Note that this is the '''accidental''' creation of an archenemy, not ExecutiveMeddling of "let's make an archenemy for X-character": a character "suffering" from The Moriarty Effect is one who was meant to be a one-shot throw-away that, through fan/author/executive/all-of-the-above response became not only a staple villain, but THE villain of the series.

In some cases, the character may never again appear in the original authors' stories, but because of the popularity of the character, subsequent authors or even [[{{Fanon}} the fans in general]] may make their parts bigger and more integral to the mythos in question, via subsequent stories, adaptations, or simply fanon.

Sometimes, these characters become [[AntiHero antiheroes]] in their own right, [[BadassDecay with all the attendant risks.]] Most often, though, they retain their wonderful BigBad status.

Compare EnsembleDarkhorse, SpotlightStealingSquad. Contrast with TokenMotivationalNemesis, a major nemesis who is killed off as soon as the first story arc ends.
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!!Examples include:

[[foldercontrol]]

[[folder: Anime and Manga ]]

* [[NeonGenesisEvangelion Kaworu Nagisa]]: Few characters have appeared for so short an amount of time (approx. 12 minutes on-screen of the 24-minute episode), yet left such an impression on any one series. Since Kaworu's appearance, and death, in episode 24 of ''Evangelion'', the fan response to his character has been so abnormally outstanding that Kaworu has appeared as a main character in nearly every subsequent incarnation/retelling/sidestory/etc. of the series, including the ''Evangelion'' manga series, ''AngelicDays'' manga, games, and the upcoming ''RebuildOfEvangelion'' series.
** He was always portrayed as an important and significant character however, he was just introduced late. And he's not exactly a "villain" either, in the truest sense; he's a creepy ManipulativeBastard but that's because he has no real concept of morality and whatnot, not because he's that way by choice. And [[spoiler: his time with Shinji seems to change this, and he basically sacrifices himself in the end so that Shinji, and humanity in general, has a chance of survival.]]
*** Honestly, he didn't do much manipulating at all in the end. He himself was actually [[spoiler:just being used by SEELE in a gambit that will either hasten Instrumentality on their terms, or screw over Gendo's Plans. Either way, SEELE wins...and Humanity, Gendo, and ironically Kaworu himself ends up losing.]]
* ''{{Yu-Gi-Oh}}'': Both Seto Kaiba and the card game, Duel Monsters (Magic and Wizards back then) were originally [[MonsterOfTheWeek going to appear only once.]] Fans got interested, and sent a cavalcade of mail. Kaiba appeared again as the villain of an arc, and played a card game at the end. Fans went crazy. Then the Yu-Gi-Oh Duelist Kingdom StoryArc came out, one thing led to another, and before long, Kaiba was arguably the number-three character after Yugi and Jounouchi, and Duel Monsters was the focus of the series. If you tell someone who hasn't read the manga that Kaiba and Duel Monsters were originally one-offs, you may make [[YourHeadAsplode their brain spontaneously combust.]]

[[/folder]]

[[folder: Comic Books ]]

* [[CaptainMarvel Black Adam]]: Captain Marvel was such a [[FunPersonified happy, fun, feel-good-superhero series]] at first... [[SarcasmMode thank christ]] that Black Adam came along. Originally intended as a one-shot baddy back in the 40's, Black Adam has [[HesBack come back in force]] since ''CrisisOnInfiniteEarths'', to become the most powerful villain/antihero of not only Captain Marvel mythos, but also one of THE most powerful villains in the whole of the DC Universe.
** All the more interesting in that Captain Marvel already ''had'' a designated "primary villain" in the form of Dr. Sivana, who debuted alongside him in ''Whiz Comics'' #2, bedeviling the Big Red Cheese with [[CardCarryingVillain a whole deck of Villain cards]] throughout the GoldenAge.
* TheJoker: Believe it or not, the villain of villains, the Clown Prince of Crime, the one crazy SOB who can make Satan shit in his pants just by laughing, was not originally intended to be ''the'' {{Batman}} villain, let alone the most well-known villain in comic history. According to the other wiki: "He was slated to be killed in his second appearance, but editor Whitney Ellsworth suggested that the character be spared. A hastily drawn panel, demonstrating that the Joker was still alive, was subsequently added to the comic." 60 years later, The Joker outshines Lex Luthor, Magneto, et all for "most recognizable villain in comics," and thanks to [[TheDarkKnight a certain recent movie]], has also become infamous as one of the most heinously evil individuals in all fiction.
** Most successful ''{{Batman}}'' villains formed through this effect. Harley Quinn's initial role was to do little more than help smooth out a punchline with a Joker character coming out of a cake, but eventually went on to be a comparable villain in much of the ''{{DCAU}}'' (and even the comics) to even the Joker.
** TheRiddler was featured in a whopping ''two'' stories in his debut year (1948) before being promptly forgotten for nearly twenty years. After being brought back into the comics (just in time for the [[{{Series/Batman}} sixties show]]), he climbed his way up to the highest tier of the Bat-Rogues almost overnight.
** [[JonathanCrane Scarecrow]] was featured in only two stories as well, neither of them memorable in the least. Then came a certain issue of ''{{The Brave and The Bold}}'' comic book that gave him his fear gas... and the rest is history.
** For decades, Mr. Freeze was a joke villain from the 60's in the same league as Calendar Man and Killer Moth. The the BTAS episode "Heart of Ice" aired, and he instantly became an A-list villain and one of the most haunting and tragic characters in Batman's rogue gallery.
** Bane was originally little more than "the guy who broke Batman's back", but was fleshed out into an ''interesting'' GeniusBruiser villain. (The key word here is "interesting".)
* LexLuthor started out as a minor if powerful villain, with only two comic appearances in the first year he was created. [[{{Superman}} Superman's]] original arch-nemesis was intended to be the now largely forgotten Ultrahumanite.
** Also, though not a character, Kryptonite was first introduced in the radio series as a way to give Superman's voice actor a rest. This AchillesHeel became a defining element of the Superman mythos.
** An [[WhatCouldHaveBeen unpublished comic book script]] well before the radio show had something called "K-Metal", which amounted to the same thing as Kryptonite. The reason the script was never published? [[StatusQuoIsGod Lois Lane found out Superman's identity]].
** Attempted and failed with Doomsday. There's only so much you can do with a character created to kill Superman. Unless you want to make his death a recurring event.
* If you were to watch any modern incarnation of the ''TeenageMutantNinjaTurtles'', you would think arch-ninja The Shredder is the end-all-be-all of Turtles baddies. Originally, though? He died in the very first issue of the original comic, and did not appear again for a long while.
* [[SpiderMan Spider-Man's]] three greatest enemies (Venom, Doctor Octopus and The Green Goblin) were all designed to be throwaway characters, had radically different origin stories originally (Green Goblin was going to be a banker obsessed with physical money ("green goblin" is a colloquialism for greed), Doctor Octopus was going to ACTUALLY be an octopus-human hybrid who failed in the same way as Curt Connors did, and Venom was originally going to be Ann Brock (Eddie's wife) whose husband is killed and who has a miscarriage due to Spider-Man fighting Cardiac - and THEN she finds the symbiote). On top of THAT they're also villains of a character who HIMSELF was created by [[TheMoriartyEffect this very trope]] during the final issue of Amazing Fantasy #15.
* [[StarWars Boba Fett]]: Boba Fett's presence in the movies was... minimal, at best. But oooooh, has he become a staple of the ''StarWars'' Expanded Universe. Much contention has been made over his survival after being ingested by the Sarlacc ([[GeorgeLucas Lucas]] [[WordOfGod says]] he died; Dark Horse comics along with most fans say he survived), but his popularity cannot be debated. Boba Fett is, to most fans, as integral to the plot as any other characters - in some respects, much more important and likable to the series as a whole.
** Lucas' opinion has recently shifted to "SureWhyNot?," and he actually considered adding in a scene of him surviving in the 2006 [=DVD=] of ''Return of the Jedi''.
** Tellingly, Boba has a bigger role as a little boy in ''AttackOfTheClones'' than he did as an adult in the original trilogy.
** Remember the scene in ''A New Hope'' where Han and Jabba converse in the hangar bay? Originally Boba Fett wasn't in the scene. He was added when the scene was finished for the 1997 re-release, partly to include another joining thread in the trilogy and partly because of how popular he is.
** Most likely, this has a lot to due with the original toy, which was not originally available through normal retail outlets. You had to send in proofs of purchase (or something like that) from other Star Wars toys. This raised interest in the character because such a big deal was made out of the toy.
* Agent Smith from ''TheMatrix'' was originally supposed to be a StarterVillain, but due to his popularity with fans he was brought back and incorporated in the storyline of the next two films as the main antagonist.

[[/folder]]

[[folder: Literature ]]

* The TropeNamer is Professor James Moriarty, created by Sir ArthurConanDoyle to be a one-time opponent of SherlockHolmes, and to bring about Holmes' demise. In fact, Moriarty was only given more than a passing mention ''three times'' in Doyle's work - the story where he appeared, and apparently killed Holmes; and the following story, which brought Holmes BackFromTheDead, and in this it's only Moriarty's men; a third story, written much later but set earlier, uses him as a brief DiabolusExMachina. ''Every'' author, director, fan, etc. afterwards, though, has made Moriarty ''the'' villain of Sherlock Holmes, lifting him to the point of mythical status among literary characters; to the modern viewer, it's inconceivable to have an original Holmes movie or television series with original Holmes mysteries without having Moriarty as the central, most important villain.
** Another "villain" to become central to the Holmes Universe (i.e. original canon ''and'' adaptations), despite her one appearance, is Irene Adler, who is the ''only'' woman to ''ever'' outwit Holmes. In Doyle's stories, he does make a few fleeting mentions of her as the only person whom Holmes never beat - though hardly as many as one might be led to expect by adaptations.
** {{Fanon}} has retconned both Moriarty and Irene into the Holmes mythos. There is now a timeline of cases where Holmes clashed with Moriarty's organization, and it's a popular ttheme in homages and pastiches that Sherlock and Irene had a tryst during Holmes's absence after Reichenbach.
** Colonel Sebastian Moran, Moriarty's [[TheDragon right-hand man]]. The story that brought about Holmes's resurrection established that he was there when Holmes killed Moriarty, even spontaneously attempting to finish the job, then proceeds to become a MoriartyEffect villain himself. One of the few characters that gets mentioned in several stories, despite only appearing in one, to the point where he's sometimes Watson's full blown EvilCounterpart.
* [[KingArthur Mordred]]: In the early mentions of KingArthur in Welsh mythology, Arthur was slain by Medraut, later to be known as Mordred. However, Medraut's importance in the mythos as a whole was almost non-existent, save for that he killed King Arthur. Other villains had come and gone, and it seemed that Mordred was intended to just be another, though the only one who finally got lucky (although Arthur slew him in the same action, so his luck is debatable). Ask anyone in modern times, however, who is THE villain of the story of King Arthur, and the answer you will get is "Mordred" almost all the time (though Morgan Le Fay is another name that also comes up quite frequently, and is, coincidentally, another example of this trope). Mordred has become so integrated into the mythos of Arthur that it is unheard of to NOT include him in any story involving the rise and fall of Camelot.
** Modern depictions of Mordred usually bump him up to being King Arthur's son with Morgan, which has a number of neat effects. First of all, it ups his status from being a random evil knight into LukeYouAreMyFather. Second, it gives him an actual motivation - he wants to be recognized as the rightful heir but Arthur refuses. Third, it makes Arthur the architect of his own demise, directly. Fourth, it ties him in with Morgan Le Fay, the other popular Moriarty of the series, so everything's wrapped up in a neat little package.
** This being TheThemeParkVersion by way of the OneSteveLimit. Originally, Mordred's mother was Morgan's sister Morgause, which ends up giving him an entire supporting cast in the form of his (half-)brothers at court - Gawaine, Gareth, Gaheris, and Agravaine. In Malory, at least, they're a bit of a FiveManBand.
** The earliest mention of Mordred is a reference to "The Battle of Camlann" where "Arthur and Medraut died". From the context (or lack of same), it's not even clear that they were on opposite sides.
*** The Welsh Triads include Mordred in a list of ''heroes''. The first unambiguous mention of Villain!Mordred is in Geoffrey of Monmouth's ''Historia'' (1100s). From there, Mordred got steadily more villainous: in Geoffrey he only speaks twice, in the Alliterative ''Morte Arthure'' (early 1300s) he's an angsty WorthyOpponent, in the Stanzaic ''Morte'' (late 1300s) he's distinctly worse, and by Malory's ''Morte Darthur'' (1470s) he's all the way into ForTheEvulz. As Malory's is the only version most non-medievalists have read, that's the characterisation that held.
* [[TheLordOfTheRings Sauron]] originated as a relatively minor villain from the earliest version of the legend of Beren and Luthien, and the proto-Sauron was a giant [[CatsAreMean cat]], of all things. The character subsequently morphed into the EvilSorcerer Thu, and from there into the demonic being known from ''TheLordOfTheRings''. In the process, he got promoted from one-shot villain to the GodOfEvil's [[TheDragon Dragon]] to the DragonAscendant to the BigBad of the most well-known part of the mythology and the second most significant villain in the Middle-earth {{Verse}}.
* The Wicked Witch of the West, thanks to the popularity of the classic ''TheWizardOfOz'' film, has become the most recognizable of Oz's villains and the BigBad of most adaptations of the Oz series (i.e. the 1980's cartoon). In the original novels she only appeared in one chapter in the middle of the first book, during which she was KilledOffForReal; the closest thing the Oz books have to a BigBad is actually the Nome King, who appeared in several books to cause trouble for the land of Oz.
* [[AliceInWonderland The Queen of Hearts]] only appeared in the last third of the first ''Alice'' book and wasn't really as much a villain as she was a tempermental yet comic battleaxe, whose executions were never really carried out. However, ''Alice'' spinoffs like ''[=~American McGee's Alice~=]'', ''TheLookingGlassWars'' and TimBurton's new movie have made her the main villain, transforming her into an evil dictator who rules Wonderland with an iron fist and Alice's greatest nemesis.
** Likewise, The Jabberwock, who only appeared in a poem in ''Through the Looking Glass'' where he was quickly killed, has become a significant villain in things like the aforementioned ''American [=McGee=]'s Alice'' and Burton film, as well as a television adaptation in which it stalks Alice throughout.
* ConanTheBarbarian - Thoth-Amon makes only a passing appearance in a few stories, but both comic adaptations make him Conan's ArchEnemy.

[[/folder]]

[[folder: Live Action TV ]]

* In ''LawAndOrderCriminalIntent'' we have Nicole Wallace, AKA That Evil Aussie Chick. Now, this being a crime show, she doesn't get THAT many appearances, but if you can outwit [[CrazyAwesome Goren]]...
* [[DoctorWho The Daleks]]: Despite challenging the TARDIS for the title of the most iconic element of ''Doctor Who'', they were created in defiance of co-creator Sydney Newman's insistence on writing a non-traditional ScienceFiction serious which would avoid [[AliensAndMonsters Bug-Eyed Monsters]]. This explains why they ''died'' at the end of their first story with no hint given that they might possibly return. Now these motorised pepper-pots have had more appearances than any other adversary and posed a threat to the Doctor exceeded only by other Time Lords and similarly SufficientlyAdvancedAliens.
* ''{{Lost}}'s'' Benjamin Linus, or rather actor Michael Emerson, was originally scheduled for a three episode stint in Season 2. His performance won the producers' everlasting affection and it was expanded to the rest of the season, and then into a regular in Season 3. If this isn't reason enough to include him, in Season 4 one of his fake aliases happens ''to be'' Moriarty.
** Dean Moriarty, though, making this an ''On the Road'' reference, as well as a nod to ''Sherlock Holmes''. (The character from ''On The Road'' was named as a reference to the Holmes villain, it still works as a reference to both.)
* Sigfried from ''GetSmart'' was originally meant to be a one-time villain, but then popped up again a few times, and is now considered the main villain of the series, even appearing (well, InNameOnly) in the 2008 feature film adaptation.
* Cavil on ''BattlestarGalactica''. In his original appearance, he actually seemed to be one of the nicer Cylons. Turns out he was lying about not supporting the genocide and was its main instigator.
** Then it turns out that [[spoiler: one of the Cavils introduced was a nice Cylon not supporting the genocide, and the other Cavils introduced was the mastermind. Alas, The Plan...]]
* Scorpius from ''{{Farscape}}'' was ''supposed'' to be a one-shot first-season villain. The performance was so effective, however, that he returned, quickly usurped the then-BigBad, and became the biggest {{Chessmaster}} this side of [[{{Gargoyles}} Xanatos]].
* ''{{Buffy the Vampire Slayer}}'' had Spike. Originally meant to be a one-season villain, and a DiscOneFinalBoss at that, he quickly went on to be one of the show's most popular characters, converting to full-fledged AntiHero by the fifth season, and continuing into ''{{Angel}}'' after the series ended.
* Although [[StarTrekDeepSpaceNine Gul Dukat]] appeared in the pilot episode of ''Deep Space Nine'', he was never intended to be a recurring character...but Marc Alaimo just played him so ''well''...
* K.A.R.R. was originally a one-episode villain on ''KnightRider'', where he was introduced as K.I.T.T.'s EvilCounterpart and ultimately destroyed at the end. He was brought back in a second episode, "K.I.T.T. vs. K.A.R.R.", due to his popularity. Despite only appearing in two episodes, he's widely remembered as the heroes' ArchEnemy and plays a prominent role in both the video game and the recent reboot of the series.
* Murdoc the MasterOfDisguise assassin on ''MacGyver''. Originally a one-episode villain, his use of creative schemes and deathtraps made him a good foil for master-of-improvisation MacGyver himself, so they kept bringing him back about once a season (due to his NeverFoundTheBody and StayingAlive tendencies), and he's now remembered as MacGyver's ArchEnemy.
* Sylar on ''Series/{{Heroes}}'' was originally planned to be the series' StarterVillain, who would be KilledOffForReal at the end of the first season. However, due to the character's popularity with fans, he was made into a main character and "The Face of Evil" for the series, to the point that pretty much every following BigBad ends up getting [[HijackedByGanon Hijacked By Sylar]] in their season's finale.
* In ''{{Sliders}}'', the Kromaggs (an AlwaysChaoticEvil AlternateUniverse race) eventually become this. Unfortunately it also marks the point where they become the MalignantPlotTumor, since the show's original WalkingTheEarth appeal had to be downtoned to make place for more action scenes.

[[/folder]]

[[folder: Videogames ]]

* [[SuperMarioBros Bowser]]: Before ''Super Mario Bros'', the portly plumber tangled with a lot of nasty foes. Donkey Kong, Foreman Spike, and random unorganized critters (though some did look similar to Koopas). But once ''Super Mario Bros'' hit the scene, it was Mario's defining moment, and from that day forth, the Koopa troop and its fearless leader would be his most prominent nemesis. This seems even more dramatic in America, where Bowser was in fact absent for a game before making a triumphant reappearance in Super Mario Bros 3. In this case it was the unforeseen popularity of the game that caused the Moriarty Effect for its main Bad Guy.
* In the original PS version of ''[[ResidentEvil1 Resident Evil]]'', Albert Wesker was just a standard horror movie stock character (the obligatory traitor who gets eaten by the monster in the end, basically Paul Rieser's character from ''Aliens'') who turns on the team only to get killed by the final monster at the end of the game. However, following his return in ''ResidentEvilCodeVeronica'', he managed to pretty quickly be built up to be the BigBad of the entire series over the course of the following decade up until his last appearance in ''ResidentEvil5''.
* While Revolver Ocelot manages to survive the events of the original ''MetalGearSolid'', there's really nothing to suggest that he is anything more than a mole planted into Liquid Snake's rebellion by the U.S. President. However, subsequent ''MetalGear'' games depicted Ocelot as a chessmaster who shifts allegiances from one faction to another, while keeping his true motives to himself.
* Sargeras started out as little more than a footnote in ''{{Warcraft}}'' lore, as a SealedEvilInACan demon lord whose powers [[EvilSorcerer Gul'dan]] tried to harness. The revelations of his origins as a fallen [[PhysicalGod Titan]] and creator of the [[TheLegionsOfHell Burning Legion]] elevated him to BigBad of the ''entire franchise''.
* [[MadScientist Wilhelm]] [[NamesToRunAwayFromReallyFast "Deathshead"]] [[RetCon Strauss/Strasse]] of the [[ThoseWackyNazis SS Paranormal Division]] gets this in the ReturnToCastleWolfenstein - Wolf 2009 series, mainly due to his status as being the sole surviving Nazi of any prominance in "Return" besides [[DoomedByCanon Himmler.]]

[[/folder]]

[[folder: Western Animation ]]

* Ixis Naugus was on his way to becoming this on ''Series/SonicTheHedgehog'' ([=SatAM=]) when Sonic and friends defeated Robotnik, but {{cancellation}} [[ScrewedByTheNetwork screwed him over]].
* ''KimPossible'''s Shego, originally "just a henchmen" to Dr. Drakken who curiously enough has also benefitted from her popularity: even though he gets outshined by his own assistant on the popularity polls it was thanks to this that he also became the second most important villain in the series.
* In the original Mirage Comics version of the ''TeenageMutantNinjaTurtles'', the Shredder was actually a fairly lackluster StarterVillain who managed to get himself KilledOffForReal at the end of the very first issue. In later issues a colony of sentient worms would take up the mantle of The Shredder (it's a long story), but even they only appeared in a few issues and played a rather minor role in the comics plotline. However, the 1980's cartoon adaptation made him the BigBad, and he's been the Turtle's ArchEnemy in every future adaptation of the series ever since.

[[/folder]]
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Compare EnsembleDarkhorse. Contrast with TokenMotivationalNemesis, a major nemesis who is killed off as soon as the first story arc ends.

** Modern depictions of Mordred usually bump him up to being King Arthur's son via Morgan, which has a number of neat effects. First of all, it ups his status from being a random evil knight into LukeYouAreMyFather. Second, it gives him an actual motivation - he wants to be recognized as the rightful heir but Arthur refuses. Third, it makes Arthur the architect of his own demise, directly. Fourth, it ties him in with Morgan Le Fay, the other popular Moriarty of the series, so everything's wrapped up in a neat little package.
** This being TheThemeParkVersion by way of the OneSteveLimit. Originally, Mordred's mother was Morgan's sister Morgause, which ends up giving him an entire supporting cast in the form of his brothers at court (Gawaine, Gareth, Gaheris, and Agravaine).
** The earliest mention of Mordred is a reference to "The Battle of Camlann" where "Arthur and Medraut died." From the context (or lack of same), it's not even clear that they were on opposite sides.

** And a couple more examples:
*** TheRiddler was featured in a whopping ''two'' stories in his debut year (1948) before being promptly forgotten for nearly twenty years. After being brought back into the comics (just in time for the [[{{Series/Batman}} sixties show]]), he climbed his way up to the highest tier of the Bat-Rogues almost overnight.
*** [[JonathanCrane Scarecrow]] was featured in only two stories as well, neither of them memorable in the least. Then came a certain issue of ''{{The Brave and The Bold}}'' comic book that gave him his fear gas... and the rest is history.
*** For decades, Mr. Freeze was a joke villain from the 60's in the same league as Calendar Man and Killer Moth. The the BTAS episode "Heart of Ice" aired, and he instantly became an A-list villain and one of the most haunting and tragic characters in Batman's rogue gallery.
*** Bane was originally little more than "the guy who broke Batman's back", but was fleshed out into an ''interesting'' GeniusBruiser villain. (The key word here is "interesting".)

*** It should be mentioned that an [[WhatCouldHaveBeen unpublished comic book script]] well before the radio show had something called "K-Metal", which amounted to the same thing as Kryptonite. The reason the script was never published? [[StatusQuoIsGod Lois Lane found out Superman's identity]].
** Attempted and failed with Doomsday. To be fair, there's only so much you can do with a character created to kill Superman. Unless you want to make his death a recurring event.

* [[StarWars Boba Fett]]: We like to call him the FOI, or Fanboy-Orgasm-Inducer. Boba Fett's presence in the movies was... minimal, at best. But oooooh, has he become a staple of the ''StarWars'' Expanded Universe. Much contention has been made over his survival after being ingested by the Sarlacc ([[GeorgeLucas Lucas]] [[WordOfGod says]] he died, Dark Horse comics along with most fans say he survived), but his popularity cannot, by any means, be debated. Boba Fett is, to most fans, as integral to the plot as any other characters - in some respects, much more important and likable to the series as a whole.

* The TropeNamer is Professor James Moriarty, created by Sir ArthurConanDoyle to be a one-time opponent of SherlockHolmes, and to bring about Holmes' demise. In fact, Moriarty was only given more than a passing mention ''three times'' in Doyle's work - the story where he appeared, and apparently killed Holmes; and the following story, which brought Holmes BackFromTheDead, and in this it's only Moriarty's men; a third story, written much later but set earlier, uses him as a brief DiabolusExMachina. ''Every'' author, director, fan, etc. afterwards, though, has made Moriarty ''the'' villain of Sherlock Holmes, lifting him to the point of mythical status among literary characters; to the modern viewer, it's inconceivable to have an original Holmes movie or television series with original Holmes mysteries without having Moriarty as the central, most important villain, including [[spoiler: ''YoungSherlockHolmes'']].

*** Interestingly enough, {{Fanon}} has retconned both Moriarty and Irene into the Holmes mythos. There is now a timeline of cases where Holmes clashed with Moriarty's organization, and it's theorized that Sherlock and Irene had a tryst during Holmes's absence after Reichenbach.
** Don't forget Colonel Sebastian Moran, Moriarty's [[TheDragon right-hand man]]. The story that brought about Holmes's resurrection established that he was there when Holmes killed Moriarty, even spontaneously attempting to finish the job, then proceeds to become a MoriartyEffect villain himself. One of the few characters that gets mentioned in several stories, despite only appearing in one. To the point where he's sometimes Watson's full blown EvilCounterpart.
* [[KingArthur Mordred]]: In the earliest mentions of KingArthur in Welsh mythology, Arthur was slain by Medraut, later to be known as Mordred. However, Medraut's importance in the mythos as a whole was almost non-existent, save for that he killed King Arthur. Other villains had come and gone, and it seemed that Mordred was intended to just be another, though the only one who finally got lucky (although Arthur slew him in the same action, so his luck is debatable). Ask anyone in modern times, however, who is THE villain of the story of King Arthur, and the answer you will get is "Mordred" almost all the time (though Morgan Le Fay is another name that also comes up quite frequently, and is, coincidentally, another example of this trope). Mordred has become so integrated into the mythos of Arthur that it is unheard of to NOT include him in any story involving the rise and fall of Camelot.

*** This being TheThemeParkVersion by way of the OneSteveLimit. Originally, Mordred's mother was Morgan's sister Morgause, which ends up giving him an entire supporting cast in the form of his brothers at court (Gawaine, Gareth, Gaheris, and Agravaine).
** Actually, the earliest mention of Mordred is a reference to "The Battle of Camlann" where "Arthur and Medraut died." From the context (or lack of same), it's not even clear that they were on opposite sides.

** Dean Moriarty, though, making this an ''On the Road'' reference, rather than a nod to ''Sherlock Holmes''.
*** Could very well be both. Moriarty was the first supervillain, after all.
*** Considering that the character from ''On The Road'' was named as a reference to the Holmes villain, it still works as a reference to both. Although, with the way they throw around names of famous people on the show, you'd think someone would call him out on the obvious CharacterNameAlias.

* [[SuperMarioBros Bowser]]: Before ''Super Mario Bros'', the portly plumber tangled with a lot of nasty foes. Donkey Kong, Foreman Spike, and random unorganized critters (though some did look similar to Koopas). But once ''Super Mario Bros'' hit the scene, it was Mario's defining moment, and from that day forth, the Koopa troop and its fearless leader would be his most prominent nemesis. This seems even more dramatic in America, where Bowser was in fact absent for a game before making a triumphant reappearance in Super Mario Bros 3.
** This is more related to ''SuperMarioBros'' being much more popular that anybody expected and establishing the basis for all future Mario games. Other than Mario's in-game sprite and basic movements, everything in the Mario games varied ''wildly'' until ''SuperMarioBros''. Miyamoto even left the Japanese ''SuperMarioBros2'''s design to Takashi Tezuka while he went on to work in "the next big thing".

[[AC: {{Anime}} and {{Manga}}]]

[[AC:ComicBooks]]

** And a couple more examples:

[[AC: {{Literature}}]]

** Another "villain" to become central to the Holmes Universe (i.e. original canon ''and'' adaptations), despite her one appearance, is Irene Adler, who is the ''only'' woman to ''ever'' outwit Holmes. In Doyle's stories, he does make a few fleeting mentions of her as the only person whom Holmes never beat - though hardly as many as one might be led to expect by adaptations.

* [[TheLordOfTheRings Sauron]] originated as a relatively minor villain from the earliest version of the legend of Beren and Luthien, and the proto-Sauron was a giant [[CatsAreMean cat]], of all things. The character subsequently morphed into the EvilSorcerer Thu, and from there into the demonic being known from ''TheLordOfTheRings''. In the process, he got promoted from one-shot villain to the GodOfEvil's [[TheDragon Dragon]] to the DragonAscendant to the BigBad of the most well-known part of the mythology and the second most significant villain in the Middle-earth {{Verse}}.

* ConanTheBarbarian - Thoth-Amon makes only a passing appearance in a few stories, but both comic adaptations make him Conan's ArchEnemy.

[[AC:LiveActionTV]]

[[AC: {{Videogames}}]]

* Sargeras started out as little more than a footnote in ''{{Warcraft}}'' lore, as a SealedEvilInACan demon lord whose powers [[EvilSorcerer Gul'dan]] tried to harness. The revelations of his origins as a fallen [[PhysicalGod Titan]] and creator of the [[TheLegionsOfHell Burning Legion]] elevated him to BigBad of the ''entire franchise''.

[[AC:WesternAnimation]]

* ''KimPossible'''s Shego, originally "just a henchmen" to Dr. Drakken who curiously enough has also benefitted from her popularity: even though he gets outshined by his own assistant on the popularity polls it was thanks to this that he also became the second most important villain in the series.
* In the original Mirage Comics version of the ''TeenageMutantNinjaTurtles'', the Shredder was actually a fairly lackluster StarterVillain who managed to get himself KilledOffForReal at the end of the very first issue. In later issues a colony of sentient worms would take up the mantle of The Shredder (it's a long story), but even they only appeared in a few issues and played a rather minor role in the comics plotline. However, the 1980's cartoon adaptation made him the BigBad, and he's been the Turtle's ArchEnemy in every future adaptation of the series ever since.

** actually bowser wasn't even real cheracter in this game. more of a Species of cretures that mario have to overcome (and kill!) in the end of each world. so- yeah it's pretty serious moriarty effect. he became from an elite-mook to the main antagonist of the francise

Not every hero has an archvillain... initially. Sometimes, though, a villain will be introduced who ends up being a [[EnsembleDarkHorse Breakout Character]] in his/her own right, and thus a [[MonsterOfTheWeek Villain of the Week]] becomes ''the'' villain of the ''series''.

** actually bowser wasn't even real cheracter in this game. more of a Species of cretures that mario have to overcome (and kill!) in the end of each world. so yeah it's pretty serious moriarty effect.

* [[SpiderMan The Green Goblin]] is an interesting case. Originally he was simply a villain with an unknown identity, which was previously unheard of in the series. Due to this intriguing concept, he eventually evolved first into Spider-Man's archenemy, and then into a CorruptCorporateExecutive who was the constant BigBad behind Spider-Man's misery.

[[AC: {{Film}}]]

** And in ''{{Yu-Gi-Oh GX}}'', Darkness/Nightshroud.

** He was always portrayed as an important and significant character however, he was just introduced late. And he's not exactly a "villain" either, in the truest sense.

** Don't forget Colonel Sebastian Moran, Moriarty's [[TheDragon right-hand man]]. The story that brought about Holmes's resurrection established that he was there when Holmes killed Moriarty, even spontaneously attempting to finish the job, then proceeds to become a MoriartyEffect villain himself. One of the few characters that gets mentioned in several stories, despite only appearing in one.

* Sylar on ''{{Heroes}}'' was originally planned to be the series' StarterVillain, who would be KilledOffForReal at the end of the first season. However, due to the character's popularity with fans, he was made into a main character and "The Face of Evil" for the series, to the point that pretty much every following BigBad ends up getting [[HijackedByGanon Hijacked By Sylar]] in their season's finale.

<<|{{Villains}}|>>

* [[StarWars Boba Fett]]: We like to call him the FOI, or Fanboy-Orgasm-Inducer. Boba Fett's presence in the movies was... minimal, at best. But oooooh, has he become a staple of the ''StarWars'' Expanded Universe. Much contention has been made over his survival after being ingested by the Sarlacc ([[GeorgeLucas Lucas]] [[WordOfGod says]] he died, most fans say he survived), but his popularity cannot, by any means, be debated. Boba Fett is, to most fans, as integral to the plot as any other characters - in some respects, much more important and likable to the series as a whole.

* [[StarWars Boba Fett]]: We like to call him the FOI, or Fanboy-Orgasm-Inducer. Boba Fett's presence in the movies was... minimal, at best. But oooooh, has he become a staple of the ''StarWars'' Expanded Universe. Much contention has been made over his survival after being ingested by the Sarlacc (Lucas says he died, most fans say he survived), but his popularity cannot, by any means, be debated. Boba Fett is, to most fans, as integral to the plot as any other characters - in some respects, much more important and likable to the series as a whole.

* TheJoker: Believe it or not, the villain of villains, the Clown Prince of Crime, the one crazy SOB who can make Satan shit in his pants just by laughing, was not originally intended to be ''the'' {{Batman}} villain, let alone the most well-known villain in comic history. According to the other wiki: "He was slated to be killed in his second appearance, but editor Whitney Ellsworth suggested that the character be spared. A hastily drawn panel, demonstrating that the Joker was still alive, was subsequently added to the comic." 60 years later, The Joker outshines Lex Luthor, Magneto, et all for "most recognizable villain in comics," and thanks to [[TheDarkKnight a certain recent movie]], has also become infamous as one of the most heinously evil individuals in all literature in general, as well.

* [[MadScientist Wilhelm]] [[NamesToRunAwayFromReallyFast "Deathshead"]] [[RetCon Strauss/Strasse]] of the [[ThoseWackyNazis SS]] [[Ghostapho Paranormal]] [[StupidJetpackHitler Division]] gets this in the ReturnToCastleWolfenstein - Wolf 2009 series, mainly due to his status as being the sole surviving Nazi of any prominance in "Return" besides [[DoomedByCanon Himmler.]]

** Attempted and failed with Doomsday. Similar to the Bane example, but failed.
** To be fair, there's only so much you can do with a character created to kill Superman. Unless you want to make his death a recurring event. He's less an archenemy than the dragon to Superman's {{Beowulf}}

*** Bane was originally little more than "the guy who broke Batman's back", but was fleshed out into an interesting Genius Bruiser villain.
**** Um, he was a Genius Bruiser before (and after) [[NeverLiveItDown he did that.]]

** Attempted and failed with Doomsday. Simalar to the Bane example, but failed.