History CharacterizationMarchesOn / WesternAnimation

* ''WesternAnimation/GravityFalls'': In Bill Cipher's debut episode, he randomly shouts a series of conspiracies just before he disappears[[note]]"REALITY IS AN ILLUSION, THE UNIVERSE IS A HOLOGRAM, BUY GOLD, BYE!"[[/note]]. It was later explained by the creator that this was part of the character's original schtick for when he was planned to just be comic relief. This part of him was quietly dropped in Season 2, when it was decided to rework him into the BigBad.

** Early episodes portayed Penguins closer to their movie counterparts, with all of them believing Rico's doll is alive, unaware when the other animals express discomfort and being more LiteralMinded and a tendency to have CloudCuckooLander moments. As the show progressed, each of them developed their personalities, only Rico believed his doll was alive, they are more socially aware and only Skipper has bizarre thoughts mostly motivated for his paranoia.

*** The aforementioned non-canon pilot has a few more examples. These include Pearl being less motherly toward Steven, with all the Gems serving as older sister figures rather than just Amethyst, and Steven having a mutually antagonistic relationship with Lars, while in the series proper, he usually seems oblivious to Lars not liking him.

** In [[Characters/TeenTitans2003Slade Slade's first appearance he was a CardCarryingVillain who spouted cliched dialogue ("[[WeWillMeetAgain Next time]] my [[ThePlan plans]] ''will'' succeed -- and the Titans will ''pay''!"), smashed teacups when he got angry, and [[ArsonMurderAndJaywalking employed a butler]]. Later episodes turned him into the creepily emotionless ManipulativeBastard ''Titans'' fandom loves to hate, gave his immediate EvilPlan a definite focus (though we never learned what his ultimate goal was), made his dialogue into what amounted to a series of very nasty [[BreakThemByTalking Breaking Speeches]] and [[WhatHappenedToTheMouse the butler was never seen with him again]].[[note]]The Butler is named Wintergreen, and he was Slade's regular sidekick in the comics. He was most likely added to the first episode with the intention of developing into the same role in the cartoon, but was then dropped in favor of Slade working alone.[[/note]]

* ''WesternAnimation/ThePenguinsOfMadagascar'': In "Gone in a Flash", Maurice was legitimate terrified of being in the middle of the penguins operations and can barely keep up with them. Later episodes would portray him as very competent and not only completely calm when he has to help the Penguins but often delighted to have a chance to participate in the Penguins missions.

*** Once his backstory and resurrection within [[ComicBook/MyLittlePonyFriendshipIsMagicIDW the IDW comics]] came to light, his previous demeanour remained unchanged, but became mixed up with a good deal of [[DarkAndTroubledPast periodic childhood trauma thanks to the same artifact]] he tried to destroy in his debut, in addition of once having been [[UsedToBeASweetChild a relatively nice, if shy and discriminated orphaned colt]], [[spoiler: who had actually been [[ManchurianAgent created without his knowledge as a spy]] by a species of vicious, [[EldritchAbomination otherwordly shadow ponies]] ]], overall making him a [[KnightOfCerebus terrifyingly competent & dreadful Antagonist]], yet [[TragicVillain becoming devasted and conflicted about his choices]], [[spoiler: which played a part in the end where [[spoiler: he [[HeelFaceTurn redeemed himself]] ]].

*** Once his backstory and resurrection within [[ComicBook/MyLittlePonyFriendshipIsMagicIDW the IDW comics]] came to light, his previous demeanour remained unchanged, but became mixed up with a good deal of [[DarkAndTroubledPast periodic childhood trauma thanks to the same artifact]] he tried to destroy in his debut, in addition of once having been [[UsedToBeASweetChild a relatively nice, if shy and discriminated orphaned colt]], [[spoiler: who had actually been [[ManchurianAgent created without his knowledge as a spy]] by a species of vicious, [[EldritchAbomination otherwordly shadow ponies]] ]], overall making him a [[KnightOfCerebus terrifyingly competent & dreadful Antagonist]], yet [[TragicVillain becoming devasted and conflicted about his choices]], [[spoiler: which played a part in the end where [[spoiler: [[HeelFaceTurn he redeemed himself]] ]].

*** Once his backstory and resurrection within [[ComicBook/MyLittlePonyFriendshipIsMagicIDW the IDW comics]] came to light, his previous demeanour remained unchanged, but became mixed up with a good deal of [[DarkAndTroubledPast periodic childhood trauma thanks to the same artifact]] he tried to destroy in his debut, in addition of once having been [[UsedToBeASweetChild a relatively nice, if shy and discriminated orphaned colt]], [[spoiler: who had actually been [[ManchurianAgent created without his knowledge as a spy]] by a species of vicious, [[EldritchAbomination otherwordly shadow ponies]], ]] overall making him a [[KnightOfCerebus terrifyingly competent & dreadful Antagonist]] yet [[TragicVillain becoming devasted and conflicted about his choices]], [[spoiler: which played a part in the end where [[spoiler: [[HeelFaceTurn redeemed himself]] ]].

*** Once his backstory and resurrection within [[ComicBook/MyLittlePonyFriendshipIsMagicIDW the IDW comics]] came to light, his previous demeanour remained unchanged, but became mixed up with a good deal of [[DarkAndTroubledPast periodic childhood trauma thanks to the same artifact]] he tried to destroy in his debut, in addition of once having been [[UsedToBeASweetChild a relatively nice, if shy and discriminated orphaned colt]], [[spoiler: who had actually been created without his knowledge as a spy by a species of vicious, [[Eldritch Abomination otherwordly shadow ponies]], ]] overall making him a [[KnightOfCerberus terrifyingly competent & dreadful]] yet [[TragicVillain]], [[spoiler: who was shown the error in his ways at the end and [[spoiler: [[Heel-FaceTurn redeemed himself]] ]].

** The villain [[Characters/FriendshipIsMagicKingSombra King Sombra]] may be the most-jarring example. In his debut (the Season 3 premiere) and his BadFuture (the Season 5 finale) -- he was CrazyPrepared and [[NoNonsenseNemesis No-Nonsense]] and [[SilentAntagonist Silent]], akin to a predator that [[ItCanThink Can Think]]. But his return (the Season 9 premiere) inexplicably portrayed him as [[EvilIsHammy Hammy]] and [[SmugSnake Smug]] to a stereotypical degree, now bear-hugging the very VillainBall he'd once avoided like the plague. And his [[TheOtherDarrin Other Darrin]] just sharpened the contrast more, making him literally sound like another character entirely.

* ''WesternAnimation/GravityFalls'': In [[Characters/GravityFallsBillCipher Bill Cipher's]] debut episode, he randomly shouts a series of conspiracies just before he disappears[[note]]"REALITY IS AN ILLUSION, THE UNIVERSE IS A HOLOGRAM, BUY GOLD, BYE!"[[/note]]. It was later explained by the creator that this was part of the character's original schtick for when he was planned to just be comic relief. This part of him was quietly dropped in Season 2, when it was decided to rework him into the BigBad.

* Before ''Film/RevengeOfTheSith'' premiered, General Grievous made his first appearance one year earlier in the Creator/GenndyTartakovsky produced ''WesternAnimation/StarWarsCloneWars'' animated series. It is a very different characterization than what would end up in the live action movie; Grievous in the animated series is a scary, unstoppable killing machine that singlehandedly defeats a number of Jedi. In the movie, Grievous is less formidable adversary and who runs when he knows he cannot defeat an opponent. This characterization has continued into the CGI ''WesternAnimation/StarWarsTheCloneWars''.

** In early episodes, Pearl doesn't seem to show any sign of disliking food: she seems to have an interest in tea in "Serious Steven" and says she likes pie in "So Many Birthdays". Later in the series -- once gems have been established as TheNeedless -- she's utterly disgusted by eating. In the pilot, all the gems seem to be fine with eating, but in the series, only Amethyst regularly does. When asked about this, one of the head writers {{handwave}}s Pearl's earlier interest in food as her just liking the act of cooking and baking.
** The aforementioned non-canon pilot has a few more examples. These include Pearl being less motherly toward Steven, with all the Gems serving as older sister figures rather than just Amethyst, and Steven having a mutually antagonistic relationship with Lars, while in the series proper, he usually seems oblivious to Lars not liking him.

** Steven is known for being TheHeart and being extremely pacifistic. This trait, however, wasn't concrete until the third season. Steven in early seasons was much more fight happy and offensive in his abilities.

** In [[BigBad Slade]]'s first appearance he was a CardCarryingVillain who spouted cliched dialogue ("[[WeWillMeetAgain Next time]] my [[ThePlan plans]] ''will'' succeed -- and the Titans will ''pay''!"), smashed teacups when he got angry, and [[ArsonMurderAndJaywalking employed a butler]]. Later episodes turned him into the creepily emotionless ManipulativeBastard ''Titans'' fandom loves to hate, gave his immediate EvilPlan a definite focus (though we never learned what his ultimate goal was), made his dialogue into what amounted to a series of very nasty [[BreakThemByTalking Breaking Speeches]] and [[WhatHappenedToTheMouse the butler was never seen with him again]].[[note]]The Butler is named Wintergreen, and he was Slade's regular sidekick in the comics. He was most likely added to the first episode with the intention of developing into the same role in the cartoon, but was then dropped in favor of Slade working alone.[[/note]]

** The second episode, "Sisters", has Beast Boy saying he wants to watch a comedy movie, while Raven wants to watch a horror film. Later episodes would establish Beast Boy as a horror and sci-fi junkie, while an entire episode is based around Raven refusing to admit that a horror film terrified her.

** In the first season, Courtney was a bit of a ControlFreak who just needed to lighten up. This went out the window during the second season, where she TookALevelInJerkass.

** In early episodes, Heather would take almost every opportunity to mess with her teammates even if it risked making her team lose, like reading Gwen's diary out loud to the whole world or making Leshawna chop pineapples (which she's allergic to) during a cooking competition. This habit seems to have disappeared by the middle of ''Island,'' as she became more focused on winning. She even gets mad at Courtney in ''World Tour'' for trying to lose the Area 51 challenge on purpose so they could vote out Gwen. She doesn't even like Gwen, but it seems she draws the line at bringing the whole team down for the purpose of single-minded revenge.

** In early episodes, Finn and Jake had a much more parental big/little brother relationship, with Finn as a well-intentioned BloodKnight and Jake sometimes persuading him to be more cautious or moral. As the show went on, Finn quickly became TheCape, with only the odd flash of teenage recklessness, while Jake became much more morally unreliable and prone to egging Finn on to be much more reckless.
** [[AnIcePerson The Ice King]] was originally more violent and dangerous than the IneffectualSympatheticVillain he would become later, even before his [[WasOnceAMan tragic back story]] was revealed. He's also [[CardCarryingVillain a lot more malicious and self-aware of the gravity of his actions]] in Season 1.

** In later episodes, Roger has a surprisingly full, active life outside the Smith house, able to effortlessly conceal his identity as an alien through a variety of [[PaperThinDisguise surprisingly effective, yet very obvious, disguises]]--which makes the early episode "All About Steve" strange to watch, where he is so desperate for human contact that the only place he can go to interact socially with others is at a [[ForHalloweenIAmGoingAsMyself sci-fi convention]]. A viewer coming to the series via the later episodes would no doubt be wondering why he doesn't just wear one of his 50,000+ disguises. Lampshaded in the commentary for "Roger Codger," the episode where Roger has to find his way from a landfill to home without being caught by the CIA, where they point out that the whole premise of the episode is somewhat worthless compared to his current persona. "Roger Codger" and some other earlier episodes also depict Roger as more beloved member of the family who, while with blatant JerkAss tendencies like the others, is actually willing to sacrifice himself to protect the Smiths. Compare this to later seasons which try to one up his [[ItsAllAboutMe self-obsessed]] ComedicSociopath persona with each episode.
** Originally, Stan was just a [[StrawCharacter strawman political]] for Republicans: hotheaded, bigoted and stupid as a foil to Hayley's liberal ways (''WesternAnimation/AmericanDad'' was supposed to be ''Series/AllInTheFamily'' for the UsefulNotes/GeorgeWBush era). Once the show went through {{inverted|Trope}} IssueDrift, however, he became more well-rounded. He also became less hypocritical -- while an early episode showed him casually going to a strip club, a later one had him act incredibly uncomfortable when his coworkers dragged him there, and he wound up helping some of the strippers get legitimate jobs.

** Archer has always been TheAlcoholic, but in early episodes, his heavy drinking often caused him to slur his words to an extreme degree and show a lack of basic situational awareness. In later episodes, he's [[ImmuneToDrugs practically immune to the mental effects of alcohol, despite still being addicted to it]] except when he drinks in '''extreme''' excess. Justified, as any toxicologist will tell you that someone who routinely exposes themselves to toxins can build an immunity over the years.

* First introduced in ''WesternAnimation/BatmanTheAnimatedSeries'', Characters/{{Harley Quinn|TheCharacter}} was originally introduced as nothing more than a minor henchwoman working for [[Characters/BatmanTheJoker The Joker]], once muttering "Oy, beauty school is starting to look pretty good about now," after being caught by Batman. The producers envisioned her as a one-shot character, though she turned so popular [[CanonImmigrant that she became part of the Batman comics]], which led to the comic "Mad Love", later adapted on BTAS, which revealed that she was an intern at Arkham Asylum who was seduced by the Joker during psychiatric sessions. And during her first handful of appearances on the show, she didn't have any fighting skills to speak of -- her role in the gang was almost entirely about infiltration. Later episodes and ''especially'' later incarnations/adaptations would put her on par with Characters/{{Catwoman|SelinaKyle}} in gymnastics abilities, and even have her as the Joker's muscle if he doesn't have any other henchmen around.

** The titular duo originally spoke with TotallyRadical SurferDude accents, and they were initially presented as two stereotypical metalhead teenagers who were not very bright, as opposed to the TooDumbToLive they later became.

** How intelligent and immature Ben himself is tend to change between series. In the Original Series (as well as the animated movies and the ''Omniverse'' flashbacks), he appeared to be of average intelligence for his age, just very bumbling and immature due to being 10/11-years-old. In the first two seasons of ''Alien Force'', he grew up thanks to a 4 to 5 year TimeSkip and became a smarter, more responsible [[TheLeader leader]]. In Season 3, his fame going over his head started inflating his ego, and from there to ''Ultimate Alien'', he became cockier and more immature, [[LetsGetDangerous with his earlier AF personality resurfacing only when things get serious]]. ''Omniverse'' then tried to get him closer to his Original Series self, and this resulted into his {{Flanderization}} into an IdiotHero with occassional LetsGetDangerous moments who cracks jokes or makes stupid mistakes even in serious situations and essentially made his 10 years old self look like a genius, despite being nearly 17 at that point.

*** In ''Batman: The Animated Series'', Batman was on the whole quite humanistic, friendly, and, while still a serious detective, was not above cracking some quips, sharing smiles and bonding with Alfred and Robin (Dick Grayson), and being a BigBrotherMentor to Robin. By the time of ''The New Batman Adventures'' he has become DrillSergeantNasty to the Bat-Family (to Batgirl and Tim Drake), very standoffish and rude (as in the case of his first meeting with Superman), and becomes a colder, and more driven hero.
*** In ''Superman: The Animated Series'', Superman began as a smart, affable, somewhat smug superhero who was more or less confident and happy in both his civilian and superhero identity. However, the invasion of Apokolips by Darkseid, which leads to Dan Turpin's death and much later his brainwashing by Darkseid, leads him to lose his naivete, his idealism, and even his reputation, becoming a little more cautious, jaded, irritable, even paranoid in ''Justice League'', with his HotBlooded nature making him a target for {{Gaslighting}} by Luthor and Cadmus, and his hatred for Darkseid nearly leading him to [[spoiler:kill himself on Brainiac's asteroid before Batman comes and teleports both of them away]].

** In [[Recap/FuturamaS1E1SpacePilot3000 the pilot episode]], Bender was defined by his depression, and he is first seen in line for a suicide booth, having been become suicidal when he found out that he was bending girders to make suicide booths. This is never brought up again, and in later episodes, he becomes the loud-mouthed, obnoxious, jerk out to KillAllHumans that we all know and love.

** Fry shows very little sign of being attracted to Leela in the first few episodes. In "[[Recap/FuturamaS1E4LovesLaborsLostInSpace Love's Labors Lost in Space]]", he says that he thinks Leela is holding out to find a guy who's a cyclops like her, and doesn't seem bothered by this at all.

* ''WesternAnimation/GravityFalls'': In Bill's debut episode, he randomly shouts a series of conspiracies just before he disappears[[note]]"REALITY IS AN ILLUSION, THE UNIVERSE IS A HOLOGRAM, BUY GOLD, BYE!"[[/note]]. It was later explained by the creator that this was part of the character's original schtick for when he was planned to just be comic relief. This part of him was quietly dropped in Season 2, when it was decided to rework him into the BigBad.

** Dale was also much more mellow (but still hated the American government) in the early days. He frequently spouted bizarre conspiracy theories but rarely acted on them. Compare that to the insane, scheming, often violent nutcase in later seasons.

** Hank is actually seen eating a charcoal-grilled burger in the first season, and actually admits it was the greatest burger he's ever eaten, despite being so in love with propane that he cares about it more than his lawn, his son, his niece, or even his wife. This would be ''unfathomable'' in later seasons, with his love of propane and hatred of all other forms of grilling/heating (one episode had him refer to butane as a "bastard gas"). Granted he probably said it just to be nice to Kahn, but even with that in mind it's still bizarre to hear him say good things about any fuel other than propane.

** Compare Rainbow Dash and Fluttershy's interactions in early episodes like "[[Recap/MyLittlePonyFriendshipIsMagicS1E7Dragonshy Dragonshy]]" to ones in later episodes in even the same season. In "Dragonshy", Dash pretty much seems to hate how meek and scared Fluttershy is. Later episodes have her occasionally frustrated, but more understanding of Fluttershy's cautious nature, better reflecting the fact that they've been friends since childhood.
** All of the Apple family to some extent. Applejack started off as a HotBlooded Calamity Jane-esque figure before taming into a more laid back TeamMom. Apple Bloom, originally [[WiseBeyondTheirYears wise beyond her years]] turned into the overly excitable leader of the Cutie Mark Crusaders (this is particularly jarring in "Bridle Gossip", where Applebloom acts as the OnlySaneMan to a growing paranoia that Applejack is spearheading). Big Macintosh, who originally spoke and acted fairly normally, eventually became limited to his trademark "Yep" and "Nnnnope" outside sparse occasions and usually acts as a NotSoStoic in most of his appearances. Finally, Granny Smith, originally a rambling decrepit old woman, became a still kooky but deceptively [[CoolOldGuy Cool Old Pony]] and, in opposite to Big Mac, began speaking full sentences.
** Twilight Sparkle started off in the pilot (and a select few early episodes) as rather acerbic and aloof, and was thoroughly lucid outside her social ineptness. By the second season however, her more neurotic traits became more prominent and most of her spotlight episodes would go on to revolve around her status as TheFinickyOne. She also became a more consistently warmer and more excitable character, to the point of occasional LargeHam tendencies.
** The villain King Sombra may be the most-jarring example. In his debut (the Season 3 premiere) and his BadFuture (the Season 5 finale) -- he was CrazyPrepared and [[NoNonsenseNemesis No-Nonsense]] and [[SilentAntagonist Silent]], akin to a predator that [[ItCanThink Can Think]]. But his return (the Season 9 premiere) inexplicably portrayed him as [[EvilIsHammy Hammy]] and [[SmugSnake Smug]] to a stereotypical degree, now bear-hugging the very VillainBall he'd once avoided like the plague. And his [[TheOtherDarrin Other Darrin]] just sharpened the contrast more, making him literally sound like another character entirely.

** In the first episode, Doofenshmirtz seems to just be randomly evil for no reason, to the point that [[LampshadeHanging he admits to not understanding his own motivations.]] Later episodes establish that he's had an absurdly miserable life starting from the day of his birth, and his evil plans are an attempt to get back at the people responsible.
** In early episodes, Candace was much more of a killjoy and could sometimes come off as an outright [[BigBrotherBully Big Sister Bully]] toward Phineas and Ferb. As the series went on, though, Candace's motives for busting and her overall attitude toward her brothers became more developed and she gained more redeeming qualities. She also sometimes pined after boys other than Jeremy (such as Charles in "A Hard Day's Knight"), but fairly quickly Jeremy became the only boy whom Candace ever crushes on.

* ''WesternAnimation/RickAndMorty'': Rick started out as a drunken lunatic and BunglingInventor whose inventions only worked well enough to be dangerous, and he clearly wasn't as smart as he thought he was. Perhaps best shown in "Rick Potion #9", where through sheer incompetence he [[spoiler:''[[https://www.youtube.com/watch?v=w2pHN6xEF1c transforms the entire human race permanently into horrifying "Cronenberg" monsters]]'' forcing himself and Morty to abandon their family for another reality]]. In later seasons, he gradually became a dangerously competent AntiHero, and CrazyIsCool besides.

** In Season 1, Patrick was slightly less ditzy and more competent (it's most noticeable in the first episode "Help Wanted"), compared to the bumbling idiot he becomes in later seasons.
** Season 1 showed Mr. Krabs to be good at culinary skills, like when he was able to turn Krabby Patties into a pizza in seconds. Later seasons depict Mr. Krabs as a LethalChef who is even worse than Squidward. Mr. Krabs would also [[PetTheDog sometimes send SpongeBob home if the sponge was overworked or sick]], most notably in "Pickles" where he (gently, no less) tells [=SpongeBob=] to take the rest of the day off when it's clear just how badly the pickle incident with Bubble Bass has affected [=SpongeBob=]. In later episodes, Mr. Krabs reacts in horror to the words "day off" and "work vacation" and often will actively drag his employees to work whether they are in a condition to work to or not.

** In "A Hard Day's Knight", Perry is shown sweating in seemingly genuine anxiety from having to pose as Dr. Wexler at the Evil-Con in front of Doof, as though he is sincerely worried that he'll be in danger if he gives himself away. In subsequent episodes, Perry is completely unflappable whether he's disguised or not (often bordering on TheComicallySerious), and any time he isn't [[OOCIsSeriousBusiness usually means that something is horribly wrong]].

** Meatwad had a {{Catchphrase}} ("The bun is in your mind") [[AbandonedCatchphrase that he never uses again]], and is also [[DeathSeeker suicidally]] [[TheEeyore depressed]] instead of being the AllLovingHero and TheDitz of the group.

** The pilot treated Cheryl as a meek ExtremeDoormat who was constantly being taken advantage of by Archer, and none of her ditzy, violent or perverted behavior was present. "Diversity Hire" also has her obsessed with getting pregnant with Conway Stern's baby, while later episodes would establish that Cheryl [[ChildHater hates children]] and finds the idea of childbirth disgusting. {{Justified}} as starting in Season 2 it's established her to be [[AxCrazy completely mentally unhinged]] to the point where she spent an entire season as [[ItMakesSenseInContext America's top Country Music Star]] and [[EasyAmnesia forgot about it in its]] ''[[EasyAmnesia entirely]]'' [[EasyAmnesia the following season]].

* First introduced in ''WesternAnimation/BatmanTheAnimatedSeries'', Comicbook/HarleyQuinn was originally introduced as nothing more than a minor henchwoman working for ComicBook/TheJoker, once muttering "Oy, beauty school is starting to look pretty good about now," after being caught by Batman. The producers envisioned her as a one-shot character, though she turned so popular [[CanonImmigrant that she became part of the Batman comics]], which led to the comic "Mad Love", later adapted on BTAS, which revealed that she was an intern at Arkham Asylum who was seduced by the Joker during psychiatric sessions. And during her first handful of appearances on the show, she didn't have any fighting skills to speak of -- her role in the gang was almost entirely about infiltration. Later episodes and ''especially'' later incarnations/adaptations would put her on par with ComicBook/{{Catwoman}} in gymnastics abilities, and even have her as the Joker's muscle if he doesn't have any other henchmen around.

*** In ''Superman: The Animated Series'', Superman began as a smart, affable, somewhat smug superhero who was more or less confident and happy in both his civilian and superhero identity. However, the invasion of Apokolips by Darkseid, which leads to Dan Turpin's death and much later his brainwashing by Darkseid, leads him to lose his naivete, his idealism, and even his reputation, becoming a little more cautious, jaded, irritable, even paranoid in ''Justice League'', with his HotBlooded nature making him a target for {{Gaslighting}} by Luthor and Cadmus, and his hatred for Darkseid nearly leading him to [[spoiler:kill himself on Brainiac's asteroid before Batman comes and teleports both of them away.]]

** Early in the show's run, there would be the odd episode where Candace would play the StraightMan to Stacy instead of the other way around like what would become the norm in most later episodes. A good example of this is "Ready for the Bettys", wherein Stacy remains completely oblivious to the fact that the Bettys essentially hired she and Candace to do all of their chores for them, while Candace catches on quickly and eventually calls the Bettys out on it.

* ''WesternAnimation/SouthPark'':
** Cartman started off as a naive, whiny spoiled brat who was little more than a {{Jerkass}} and something of an InnocentBigot. It wasn't until Season 5 that he settled into his modern characterization: a devious, bigoted sociopath prone to manipulation and elaborate schemes, often for [[EvilIsPetty an arbitrary and petty goal]].
** Stan and Kyle started off as bratty {{Jerkass}}es and bullies themselves who were naive to the ways of the world but still often served as the OnlySaneMan. Later seasons developed the two more; Kyle became a crusading Soapbox Sadie and Stan an apathetic cynic who generally didn't stoop to pointless cruelty and misbehavior for the most part.
** While Kenny arguably changed the least of the four boys, his characterization evolved as well. Early seasons had Kenny as a YesMan to Cartman who often aided in his amoral schemes, whereas later seasons established him as the most morally upright of the boys. [[TheyKilledKennyAgain He also died less frequently]], mainly due to the writers running out of ideas on how to kill him.
** Randy and Sharon swapped roles over time. In early seasons, Sharon was prone to hysteria and fits of craziness, whereas Randy was a strait-laced UnfazedEveryman. Later seasons had Randy as a BumblingDad prone to taking the most ridiculous things as SeriousBusiness, while Sharon was the OnlySaneMan trying to get him to stop.

* The main trio's dialogue in very early episodes of ''WesternAnimation/SpaceGhostCoastToCoast'' is [[StylisticSuck very stilted and awkward]], in reference to how they spoke in [[WesternAnimation/SpaceGhost the source material]]. In later episodes their dialogue would become a lot more casual.

** Various members of the Council of Doom had wildly different personalities in their very first appearance. Brak simply performed a ''WesternAnimation/BeavisAndButthead'' impersonation with Sisto, compared to the loud ManChild he became afterwards. Tansit had a completely different voice actor, and was more menacing and less of a meek ButtMonkey, and Mettalus actually spoke comprehensible English instead of [[TheUnintelligible incomprehensible mettalic droning.]]
* ''WesternAnimation/SpongeBobSquarePants'':

* ''WesternAnimation/TeenTitans'':

** This happened to the third season's BigBad, Brother Blood. In his first appearance he was [[LargeHam hammy]] and [[SmugSnake egotistical]], true, but he mostly overacted only when playing to an audience and could be quite calm and suave when he wanted to, and took his defeat at the end of the episode quite calmly. Later episodes made him into a much more hotheaded villain prone to outbursts of temper whenever things went wrong, and he largely lost his "Evil [[Comicbook/XMen Professor X]]" shtick to become a much more straightforward DiabolicalMastermind. Also crosses over with Flanderization, as his obsession with Cyborg slowly ate up his entire character, to the point that his last appearance was ''entirely'' centered on stealing Cyborg's tech and upgrading his minions (and himself) with it.

* In ''WesternAnimation/XMenEvolution'', Lance was originally a jerk ass with a known hair trigger temper and even a manipulative side, and was to some extent a dark mirror version of Comicbook/{{Cyclops}}. In Season 2, however, they then established [[DatingCatwoman he had a crush on Kitty]] and pretended to be nice to get to her. After they broke up, he became a JerkWithAHeartOfGold who, while willing to plot against the X-Men, was also unable to leave a helpless old woman to die, and teamed up with them to stop an explosion. [[Comicbook/{{Quicksilver}} Pietro]], originally a SmugSnake, took over as the Brotherhood's leader and a BIG ManipulativeBastard, basically being the exact opposite of Cyclops. Only Blob and Toad really retained much of their original personalities, and even there, Blob lost his anger, and Toad lost any competence he had (originally being able to hold his own against Nightcrawler).