Character Derailment/Western Animation

"Tom/Jerry: You talked!!
 * Like the Kelly Bundy example, Luanne from King of the Hill started out as a somewhat promiscuous teenager who didn't take crap from anyone and, despite being Book Dumb, had some intelligence (the episode that fully introduced Hank's father, Cotton, revealed that Luanne can fix a car, despite Cotton's "Stay in The Kitchen" views on women). Later episodes turned her into a shy moron who was afraid to stand up for herself (and when she married Lucky, her naivete and lack of intelligence were greatly exaggerated to childlike levels). The promiscuity, however, was given a proper episode (where Luanne joins a group of promiscuous people who want to be born-again virgins) when it disappeared.
 * Bobby Hill was similarly much less effeminate in his early years. It could be argued as Character Development though if you didn't take well to his original characterization as a "Well Done, Son" Guy who's slow, awkward, and, in the words of Hank Hill, "not right." Sure he got effeminate in later episodes, but he got also got some charisma and charm, even if it was limited to being a class clown. He also went from a shy, reclusive fat kid to someone who has friends, a girlfriend, is sure of himself, and has proven to both Hank and COTTON (the episode where Cotton takes over his military school, and goes one day longer in "The Hole" than Cotton managed) how much of a badass he is. All while not changing himself to fit how they think he should be.
 * On the other hand, some consider  to have undergone a case of derailment during , which retcons his grudge against the Japanese despite him having  . This gained the episode criticism from some viewers since while Cotton was not well liked, the way he   was considered development.
 * And don't even get started on Peggy.
 * Depending on which side of the ever expanding break you stand on, Transformers: Beast Machines may have done this to pretty much everyone, via a poorly done mass Freak Out, turning Rattrap from a sneaky-but-reliable Jerk With a Heart of Gold into a sneaky-but-reliable Jerk With A Heart Of Lesser Quality Gold That Is Still Gold, Optimus Primal from a competent and inspirational yet down-to-earth and approachable leader into a spiritual guru who bordered on fanaticism, Dark Action Girl Blackarachnia into the Shallow Love Interest deprived of her boyfriend, etc, etc. Especially bad regarding Megatron who got no explanation as to why he became obsessed with eliminating individuality and hated Beast Modes.
 * Although that's a fair cop for Megatron's unprecedented manias, it's arguably justified for the Maximals, given the impact of the massive shock of rapidly going from having won the Beast Wars with Megs as their captive to suddenly finding themselves mode-locked, downgraded, amnesiac and on the run from a massive army of drones amidst the newly post-apocalyptic landscape of their homeworld, and realising that the entire population have had their sparks ripped out and stockpiled. Planetary genocide is a pretty good motivation to shake your personalities up a fair bit, so for some viewers this was more a case of justified (if not necessarily welcomed) Character Development.
 * Honestly, people have turned into religious fanatics over much, much less than what Primal had to deal with (not only has his entire race been wiped out, he's indirectly responsible).
 * Actually, Rattrap was probably the worst offender. In Beast Wars he hated the 'cons more than any of his fellow Maximals and was incredibly resourceful in combat situations (he even had an entire episode, "A Better Mousetrap," dedicated to his resourcefulness), but in Beast Machines he made a deal with Megatron himself, a guy he'd already loathed even before he decided to wipe out their entire race, just because he found out his new body didn't have weapons. Thankfully they got him somewhat back on track after that, having him fight by improvising or building weapons like the plant grenades, but that episode was still pretty jarring.
 * Of course, a lot of the character changes occurred because the writers were explicitly instructed not to go back and watch through the previous series because they didn't want it to be "too continuity-driven."
 * Then there's Silverbolt. Because  had been enjoyable on some level, he spends the rest of the series wracked with guilt and having nothing to his personality beyond it... more than any of the others, he's Silverbolt In Name Only. The writers said they'd planned for it to be a growth from the Adam West Batman of Beast Wars Silverbolt to the Dark Knight of the Beast Machines Silverbolt, but that's not what we got at all. If you want to put it in comic book terms, what you really had was Speedball into Penance. Worse was the fact that   we lose to the Bleedball version of Silverbolt.
 * No mention of Rhinox? Quite possibly the biggest derailment of them all.  Great job, writers. Real top notch work there. It was intended for Rhinox to be a lot more reasonable about it, explaining exactly why he thought this now, but Richard Newman's delivery of the lines made him sound like he had gone insane. A lot of fans pretend that the Vehicon programming was still affecting him, and it's also worth noting that he
 * Many of the characters in Thomas the Tank Engine have suffered from derailment... thankfully not literally. Edward, previously an old, kind and wise engine, became younger and ruder in later seasons.
 * It's not just Edward that this has happened to. Percy went from a mischievous Cloudcuckoolander to a naive, forgetful moron who can't pronounce simple words, Toby was a kind and confident Cool Old Guy but later became a wimp with self-esteem issues, and Skarloey, previously one of the oldest and wisest engines on the island, is now childish and afraid of everything (from thunderstorms to the incline yards to the wharf). Thomas himself was once depicted as friendly and helpful, if somewhat cocky and brash. He's now a poorly-written Creator's Pet Stu that is obligated to make appearances in every single episode (even episodes about the narrow gauge engines!) and dispense advice to everyone.
 * Johnny Bravo was, in the first season, a largely unflappable jock who tried a little too hard to impress the ladies, and who wasn't too bright but could occasionally be quite clever. In seasons two and three, in a case of Depending On the Writer, he turned into a childish, idiotic Jerkass who Screams Like a Little Girl.
 * Ben 10's Darker and Edgier sequel, Ben 10 Alien Force, has Ben and Gwen exhibit different personalities than before, but that's excusable since it's been five years and they've matured. However, there is NO explanation for the change in Kevin, who not only has suffered massive Badass Decay, but is now a good guy for poorly constructed reasons and shows no signs of the sociopathic cruelty he did in the original series. Now all he can do is be blunt (especially about his crush on Gwen, which came out of nowhere.), demonstrate The Worf Effect, drive them around in his beloved car, and occasionally thrive off of his reputation from back when he was an actual threat.
 * Vilgax went through some change as well; while he was a Complete Monster in the original show, Alien Force portrayed him as Lawful Evil (though it last only one episode and it's strongly hinted he was actually posing as such for his own advantage; in later episode, he has no problem breaking laws); later, Ultimate Alien portrayed him as a Manipulative Bastard, which, while being some derailment in a way, was actually good and ended up being an Author's Saving Throw after the Badass Decay he had suffered in Alien Force.
 * After all of Alien Force passed with no fixing of the problem, the writers finally pulled a season-long Author's Saving Throw in the first season of Ben 10 Ultimate Alien as to why Kevin is so different now, and finally connecting his character back to how it was in the original show. Unfortunately, once that was through, it was brushed aside and forgotten about, and Kevin returned to his "old new self".
 * Ben is now giving certain villains death threats, which seems very out of character as he seems to be the type of hero who wouldn't kill, now he's slowly going Anti-Hero and turning into Jason Todd from Batman, and well, Jason has the personality to justify that kind of behavior, Ben does not. Also, Gwen has become less "mature and responsible" and more "perpetually serious and angry".
 * Charmcaster
 * The Simpsons is a major offender: Homer going from a well-intentioned buffoon to a cartoonish idiot to a total Jerkass who has ZERO empathy for those around him, Marge going from a sensible, down-to-earth woman to ditzy, snappy housewife, Bart going from an underachieving prankster and troublemaker to a cold, depressed, bitter delinquent, and Lisa going from an idealistic child genius to ultra-liberal, snobbish, shrill, activism-obsessed, hate-filled mini-teenager.
 * Maggie turned out pretty good, though. She went from cute baby with a pacifier to cute baby with pacifier who can fire a gun!
 * Flanders, when he first appeared, was a perfectly nice guy. Yes he was religious and more than a little repressed. But he wasn't hurting anyone and he seemed to love all people unconditionally...in fact the whole JOKE was that Homer hated him for NO reason. He was the kind of neighbour most people would be lucky to have...friendly, kind and always willing to lend you whatever you needed. Then came his Flanderization, where he went from a generally nice guy to his ludicrously meek, inoffensive, and Christianity-obsessed persona. The derailment kicked in later, when the Simpsons writers decided they wanted a Right-Wing Christian Strawman to mock and so they derailed Flanders to make him fit the bill.
 * And maybe this is more Early Installment Weirdness than character derailment, but in Flanders' very first appearance he was so thoroughly insensitive to Homer's obvious financial troubles that he came across as a complete Jerkass fully deserving of Homer's enmity.
 * Flanders' character derailment has reached an even worse low in season 23...after
 * C. Montgomery Burns went through Villain Decay like hell. In early seasons, Burns was a downright sadistic and evil old miser who generally treated his employees like crap, stole from children, tried to block out the sun (for money), and at one point planned on turning a litter of puppies into a fur coat (which even he couldn't do). Turn to later seasons and he's just a feeble old man who is more ineffectual than anything else and serves more as fodder for jokes about the elderly than anything else.
 * Burns was always going to turn the puppies into a coat. The only one he had reservations over was the one who stood on his hind legs like Rory Calhoun.
 * Quite a few characters in Family Guy have also warped considerably since their first appearances, especially after the show's return to production in 2005. Among the many examples, Stewie, previously a humorously sociopathic Enfante Terrible with matricidal tendencies, now seems to simply be Brian's effeminate sidekick, while Brian has changed from a snarky intellectual ironically portrayed as vastly more intelligent than his owner Peter, to mainly a preacher for the writers' liberal political views and The Chew Toy concerning his inability to quit drinking and hold a relationship. Lois, while at first as the down to earth one of the family, albeit with a somewhat healthy sexual appetite, has become pretty much an insane nymphomaniac. Meg has evolved from merely a unpopular high-school girl trying to find her voice to a Butt Monkey Yandere Emo of epic proportions. Peter himself, while always a bumbling idiot but with slightly good intentions (like Homer Simpson, only fatter, drunker, and more into pop culture from the 1970s and 1980s), has become quite the irritating Jerkass Karma Houdini (making Homer Simpson look like the clueless, yet caring Bumbling Dad he was in the early days of The Simpsons), though this has been toned down somewhat in later episodes. The fact that no real straight man remains has become the show's downfall.
 * Not to mention recurring characters like Cleveland who often dispensed simple wisdom and often kept Peter in check during some of the wilder schemes. Quagmire went from being a Casanova Wannabe to a sex-obsessed freak (though "Jerome Is The New Black" did have a Freudian Excuse for that: ), Joe became overly macho to compensate for his handicap as opposed to his original character which was more like a good cop who happened to be crippled, and Mort who just became every Jewish stereotype you could imagine (despite not appearing much in the later episodes).
 * Quagmire seems to be ungoing an unusual second derailment in recent episodes, with his intense (and randomly produced) hatred for Brian becoming the focus of a lot of his humor.
 * There's something to be said for the character derailment of Cleveland Jr. for the run of "The Cleveland Show" how he used to be a hyperactive child to a fat and slow teenager (though considering that Cleveland, Jr. disappeared after he kicked around a golf ball like a soccer ball in "Fore Father," who knows what could have happened to him between "Fore Father" and his appearance on "The Cleveland Show"'s pilot episode?).
 * That could be justified with Cleveland Jr. becoming medicated.
 * Stewie's derailment reached a new level in the episode "Halloween on Spooner Street", in which some bullies stole his bag of candies and he...runs away crying. He later shoots a rocket at them and immediately worries that "maybe it was too much". Yes, this was the same Stewie who once kidnapped and tortured a boy who stole his trickey. Even in seasons 2 and 3, where he was much calmer and less hell bent on killing Lois, he showed no mercy to people who messed with him. Now, he's a total wimp.
 * Lois' character changes could be at least somewhat justified. Being married to and living with a man like Peter for years could easily drive the most sane, sensible person crazy. One episode even implies this by showing a tumor in her brain after she mentions bottling up all the stress that Peter causes her.
 * Despite mass Flanderization, most of the characters on Spongebob SquarePants retained some level of their original personalities. Plankton however started out as a competent, aggressive and maniacal villain. Once The Movie rolled around he lost much of the latter in favor of being either too obnoxiously happy with the few moments he seems to succeed, or constantly moaning and crying about what a failure he is. He's also lost a lot of competence, to the point that his Deadpan Snarker computer wife often has to tell him how to do every basic step (even blink) with Plankton often taking credit for her suggestions.
 * Mr. Krabs is just as bad, going from greedy and selfish but a good heart beneath it all and a positive character compared to Plankton, to a complete and utter Jerkass who is WORSE than Plankton, yet is still treated like a good guy and gets away with most of his crimes.
 * Spongebob himself may have gotten the worst of this. He started out as a naive, yet kindhearted guy who cared about everyone no matter what, and had the innocence of a child, to an obnoxious, nosy manchild who pesters everyone he knows to play with him, he is often careless of others' safety, and cries and screams when his "friends" aren't around.
 * While the fanbase seems completely divided whether Daffy Duck's Flanderization during the 1950s from a bombastic Cloudcuckoolander into a Jerkass Small Name, Big Ego counts as derailment or development, most agree it crossed the line during the De Patie Freleng era shorts, where he was evolved into a humorless, Faux Affably Evil villain for Speedy Gonzales. One could take it as a double-sided coin, as pitting Speedy against a more conniving villain did at least allow him to come off as more sympathetic and fallible more often than he did against Sylvester, though it still would have been a swifter transition with a more fittingly-callous character.
 * He's even worse in The Looney Tunes Show while he does have of his Cloudcuckoolander and Jerkass moments he is now a total dumbass, he can't read or write, he can't answer even the simplest trivia questions correctly, he doesn't understand the concept of stealing, doesn't know the concept of time, etc.
 * Bloo in the Pilot of Fosters Home for Imaginary Friends and Bloo during the main show are practically two different characters.
 * To elaborate, Bloo in the pilot and some of the earlier episodes is a friendly and well-meaning but mischievous imaginary friend who likes to have fun. In the rest of the series he's just a Jerkass who will do anything to get what he wants and loves being stupid and breaking the rules.
 * In the first few episodes, Bloo was still sort of the nice but mischievous character he was in the pilot, but was driven sort of neurotic by Herriman's obsessive rules. Even during these episodes, he seemed to be subtly shifting toward being ruder and ruder.
 * Also, Madame Foster. According to everyone else on the show, she's supposed to be the sweetest (and coolest) grandma ever and an absolute saint of a human being; in some episodes, she does live up to this repuation. Yet in the infamous Season 3 episode "Foster's Goes To Europe", she ruins an European vacation which the gang planned to go on (and spent the entire episode struggling to get ready for) by stealing eight-year-old Mac's tickets at the very last minute. The episode ends with Madame Foster, her bowling buddies and a homesick imaginary friend called Eurotrish going on the vacation instead, while poor Mac is wrongly and unfairly blamed by everyone else for missing the trip. In the same exact episode, Madame Foster also unties a group of defenseless imaginary ballons which sends them flying into the sky (and inevitable demise). For no reason at all. None. Wonderful lady indeed!
 * Numerous examples after the first season of the Total Drama series.
 * Trent from Total Drama Island to Total Drama Action. Trent started out in TDI as the closest thing to a normal teenager: sweet, smart, nice, and talented. He develops a thing for Gwen and they end up going out on the last episode. By the fifth episode of TDA,
 * Geoff and Bridgette (or 'Gigette') lost both their personalities once they became an Official Couple and were only used for makeout gags, Geoff suffered from Acquired Situational Narcissism during the Aftermath segments and Bridgette ended up becoming a Clingy Jealous Girl during the TDA special and even
 * It's only going to get worse. That same Clingy Jealous Girl will be  Hypocritical Humor or Double Standard?
 * Courtney went from a whiny but tolerable Small Name, Big Ego who had a sense of honor in playing the game to
 * Thankfully, as of the special, she's snapped back a bit, and gotten a more realistic plot of her
 * Aaaand it seems they've driven her right back off the rails after  Being furious and upset over the incident at hand is one thing, but actually losing challenges on purpose to spite Gwen? Good lord, what has happened to the ultra-pragmatic Courtney from Total Drama Island!?
 * Gwen on Total Drama World Tour does an example of Moral Dissonance by kissing Duncan while he was still with Courtney. She feels some remorse at first but when the kiss is found out she doesn't try to vote herself out like last season or apologize. And later she manipulates Cody's feelings for vote Courtney off. She's even lampshaded as being "New Heather".
 * Leshawna, most definitely. The first season had her as a girl who would take crap from nobody and could get quite feisty, but still very kind and friendly, to the point where her "elimination" came in part because everybody who had been eliminated at that point liked her so much. Then comes TDA, where she does manipulate her teammates into giving her a reward by pretending to cry and being sentimental. And here comes World Tour, in which she's somehow become a huge, arrogant jerk with little to no redeeming qualities, and goes right back to hating Heather even after supposedly making up with her in TDA; even beating Heather up when Heather is trying to warn her about Alejandro's treachery and, after learning that she was right, is still proud of doing it.
 * Duncan also qualifies because during his return in World Tour he seemed to hold the Conflict Ball, he cheats on Courtney with Gwen, he never helps his team, cheats during the game, treats everyone (other than Gwen) like crap, especially Courtney, became a Manipulative Bastard and helped Alejandro stir the pot.
 * Owen also counts. He started out as a friendly and completely clueless big oaf who everyone loved and who didn't play the game strategically. In TDA, he becomes a self-centered Small Name, Big Ego and Jerkass who can't stop himself from eating for one second. Later comes TDWT were he has dropped the Small Name, Big Ego and Jerkass traits but now he actually THINKS STRATEGICALLY.
 * Go watch Cosmo in the earlier seasons of The Fairly Odd Parents. It was established in the first season that he ran away from home to marry Wanda. In another episode he broke down from having to be away from her overnight. It was very clear they enjoyed their relationship. Then, suddenly, in seasons four and five he was drooling over every attractive woman that came onscreen, repeatedly calling Wanda a nag and more, and acting like she had Bound and Gagged him at the altar. Hell, go watch the original Oh Yeah! Cartoons shorts of Fairly Oddparents. Compare the calm, deeper-voiced Cosmo who was Wanda's equal intelligence-wise and actually seemed to share a loving relationship with his wife. Now, compare that to the sociopathic Man Child with the screechy voice portrayed in the Fairly Odd Parents series and see how far he fell. It's rather handy, you can tell his intellect by his voice pitch. Deep/slightly high voice, reasonable degree of smarts, really high voice, no smarts.
 * Remember when Wanda happily admitted to, along with Cosmo, being "two halves of a whole idiot?" Now she's smart and Cosmo is just one whole idiot.
 * Remember when Vicky used tapes, recordings, personal belonging-destruction and other tiny bits of humiliation to torture Timmy? Now she's armed to the teeth with chainsaws, maces, and other over-the-top weaponry that isn't used for a good gag, with her cackling maniaclly all the while. This derails Vicky from far-back as the first episode, where she clearly shows she'd never want Timmy to suffer any serious physical harm, let alone be the cause of it, because her well-paying job depends on him being kept in-tact.
 * Considering all of its faults, many agree that one of the greater atrocities committed by The Secret of NIMH 2 was entirely derailing the character of Brutus; changing him from a white-eyed, silent, spike-wielding gatekeeper into...a blundering, idiotic side-kick to the also-somewhat-derailed Justin.
 * It should be noted that the original book Ms Frisby and the Rats of NIMH did actually reveal Brutus to be a pleasant guy just playing the shadowy guard act to scare away intruders. Similar to the Aunt Shrew example, it is more the fault of both films for not elaborating on this enough.
 * Also, Martin got tortured into becoming inexplicably evil, complete with a hammy British accent performed by Eric Idle (though due to the hilariously ridiculous lengths this is taken, some see it as positive derailment).
 * Or Aunty Shrew scolding Martin for badmouthing Nicodemous and insisting that he was a great oracle or something - despite the fact that she clearly was shown in the first movie distrusting the rats (though it's possible she thought better of them after they helped the Brisby family, there really isn't any mention of this).
 * The first Tom and Jerry animated movie not only had the title characters (who are supposed to be, you know, pretty much mute) talk... it had them sing. And be friends. You know, the same cat and mouse who are supposed to be bitter enemies are singing about friendship.
 * The Character Derailment actually happens within the movie itself, as Tom and Jerry spend the first ten minutes of the movie as their normal, mute, bitter enemy selves (though Tom does save Jerry from the collapsing house, it feels more like one of the Enemy Mine moments they'd occasionally have in the original shorts), until the dog convinces them to be friends. For about a minute, and their first bits of dialogue, they seem to cling desperately to their characterizations as enemies, as well as engaging in some admittedly pretty funny Lampshading of the sudden shift:

Tom: Well, sure I talk! What do you think I am, a dummy?

Jerry: You said it, I didn't!

Tom: Ah, you little pipsqueak! I oughtta -- *pause* Hey! How come you never spoke before?!

Jerry: Well, there was nothing I wanted to say that I thought you'd understand... and there STILL isn't!"

And Onua, the wisest and most level-headed of the Toa, who always chooses the most effective yet least risky path in every battle (it's written in his official bio), is portrayed here as a slow-minded brute who puts his partners in danger with his actions, and causes the destruction of his hometown, and almost the death of his entire team.
 * Unfortunately, shortly after this they're goaded into singing the Big Friendship Song, which marks the definite moment when the Character Derailment can no longer be denied even by the most goodwilled fans.
 * Scott Summers/Cyclops on Wolverine and The X Men. In his origin episode Breakdown Cyclops, who has been depressed and ineffectual since losing his girlfriend Jean Grey, is revealed to have been extremely stupid and clumsy when he was first recruited to train as an X-Man. This apparently changed when Jean came into his life and "took the pain away" as Emma Frost, the rival love interest, put it. This is a big turn from the comics, where Cyclops was always a good, diligent X-Man, even as a student, where his primary problem was that he had weak social skills. This alternative characterization however embarces the stereotype that he is nothing without his long time girlfriend, while not showing anything suggesting he was ever a competent heroic leader.
 * Hell, lets say EVERYONE was derailed to some extent, literally the only exception is Nightcrawler, they all become massively incompetent, just to make Logan's Canon Sue aspects all the more apparent.
 * Due to Sequelitis, Belle from Beauty and The Beast. The Nostalgia Chick was mighty upset over Belle putting up with the Beast's temper tantrums and becoming his cheerful "life coach" in Beauty and The Beast The Enchanted Christmas. She's worse in Belle's Magical World.
 * Granddad on The Boondocks: In the first season, he was one of the two straight men, generally went his own way and couldn't stand his grandsons insufferable Huey or no-good troublemaking Riley and didn't hesitate to take off his belt and give Riley an ass whooping whenever he had it coming. He's now a full-on Jerkass abusive grandparent who wants to seem young and hip, obsessed with money & "bitches", and blindly follows along with whatever dishonest schemes Riley has planned to get rich quick, over Huey's loud and sensible objections. Granddad over the course of 3 seasons came to embrace all of the black stereotypes Aaron McGruder has been making fun of (when it was just Riley).
 * Characters in the PBS show Arthur would fall victim to this in later seasons. It is especially poignant with episodes written by Dietrich Smith, though it varies depending on who writes. This is especially problematic, particularly among older fans, as Arthur is that kind of show with an established continuity and set character personalities.
 * In almost a reversal of the aforementioned Bloo example, Rufus and Amberley of The Dreamstone, despite always being cutesy and cheery protagonists in contrast to their enemies, had some visible cynical traits and flaws in their own right in the pilot (Rufus was a Cloudcuckoolander Badass Adorable while Amberley was moody tempered and sarcastic) and had almost an equal focus in sympathetic spotlight and humor as the villains. In the majority of later episodes, the two became ridiculously juvenile and innocent, to the point their interaction was often extremely uneventful until the Urpneys attacked them every episode.
 * EVERYONE in the Watership Down series adaption. Everyone. Hazel is suddenly in love with Primrose after about two episodes, Hyzenthlay was completely replaced altogether. Bigwig, in both the book and movie, was a bold, strong and knowledgeable fighter. Here he's turned into nothing more than a complainer and follower to Hazel, who doesn't know anything in war strategy. Pipkin, previously nervous, but extremely loyal, is turned into a Cheerful Child. Kehaar... became unrecognizable. Even Woundwort - the genocidal, slave-driving Big Bad who eats hawks for breakfast and in the book contemplates how some day he hopes to meet a stoat so he can kill it, and remember he's a rabbit - had a period in the series where he tried to STOP THE WAR WITH WATERSHIP DOWN. And OPENLY SHOWED REMORSE for what he'd done. There's more.
 * While the Character Derailment from the book is fairly rampant, the show suffers a second round at the start of the third season, when the show also had a drastic change in art style and writing. Woundwort is hit the very worst. The season transition happens in the middle of the final battle with Efrafa, leading to a painful moment where Woundwort realizes the error of his ways and tries to stop the war. He's then struck by lightning and the warren collapses. He digs himself out afterwards and declares that he will have become a force of destruction, rather than simply a totalitarian dictator.
 * Takua and Onua in the first Bionicle Direct to Video animated movie. The former was originally an adventurous and brave character who valued duty and helping others (even if he had just met them) above all else, and who would be among the first to volunteer for dangerous quests. In the movie, an easygoing slacker who shoves his duty on others, cowers in the face of danger, and abandons his friend to do his work for him (a friend he tricked into believing it was his work in the first place). It takes the destruction of several villages and seeing his heroes fall for him to realize this is no time for goofing off. Very striking, as prior to the movie's events, he was hailed as a war hero.
 * Stanley has a minor version: For the first few episodes, Lionel acted like your standard Big Brother Bully. Then, as if overnight, he become a Cool Big Brother.