Shapeshifter Mode Lock / Anime & Manga

• Haji of Blood+ suffers from this in a way. After being prematurely awakened in 1972 Vietnam, Saya went on a bloody rampage and severed Haji's right hand. Though it was reattached, it is now permanently stuck in chiropteran form, and he constantly keeps it bandaged up except when The Gloves Come Off.
• BNA: Brand New Animal has Michiru suffer from this for a while. While she does have the unique ability to morph body parts in her anthropomorphic tanuki form, she's spent several months unable to accomplish the mundane Beast Man ability of shifting back to their default human form due to having Just Woke Up That Way rather than be born as a beastman. She does learn how to do this after a few episodes, but by that point she decides to have tanuki be her Shapeshifter Default Form anyway.
• Keel's goal of undoing his human transformation in Buster Keel!. He does manage to gain a few items that let him temporarily transform his arms to their original forms for fighting.
• Cardcaptor Sakura: Episode 58 has Eriol cast a spell on Kero and Yue so that they are unable to return to their disguise forms. Sakura eventually fixes the problem by using the Shield Card on them.
• In Claymore the more a Claymore uses her Youki power, the more her body transforms into a Youma — the very thing they hunt (since they are part Human part Youma). If they use up 80% of their Youki power, they fully turn into a Youma and cannot transform back into human form and hunter will become the hunted (apart from some rare exceptions).
• In the second season of Corrector Yui, the corrector Synchro, who had spent almost the whole first season trapped in the form of Corruptor War Wolf, was forcibly reverted to his War Wolf shape when he was attacked and infected by a powerful virus.
• Digimon Tamers was the first series to explore this aspect of E[Digi]volution — both Guilmon and Terriermon have some trouble in coming back to their Child/Rookie forms after the change; there was even an entire episode showing the problems in hiding the huge Growlmon in the real world. Eventually this aspect was downplayed, since they spent some 20 episodes in the Digital World, and after that the Digimon's existence was known by the public.
• One chapter of D.N.Angel had Dark in control of the body after Daisuke went missing (sort of) on White Day.
• Dragon Ball
  • In the early part of the Androids saga, Freeza can only stay in his final form, due to his mechanical parts from being severely injured during his fight with Goku.
  • In the Buu Saga of Dragon Ball Z, the Old Kai warns Goku that fusing via the Potara earrings while in Super Saiyan form will lead to the fusion being unable to power down, when Super Saiyan can normally be activated and deactivated at will. On top of that, the strain that Super Saiyan puts on the body could prove lethal.
  • This point comes up later in Dragon Ball Super, when Future Zamasu and Goku Black fuse into Fusion Zamasu using the earrings. Goku Black is in his Super Saiyan Rosé form at the time, which should bring up this issue. However, the fusion inherited Future Zamasu's Complete Immortality, a trait that prevents the mode lock's lethality and gives it even more power. This does come with some downsides, though; when Fusion Zamasu is hit with enough energy, half of his body starts mutating, since his immortality didn't fully extend to his mortal half, and thus can't fix the damage like it would for Future Zamasu.
• An example from Fairy Musketeers: Val used to be a werewolf. However, thanks to injuries he sustained while protecting Akazukin's home village from other werewolves several years before the series began, he's now trapped in wolf form.
• In Fullmetal Alchemist: The Conqueror of Shamballa, Envy transforms into a dragon before going through the Gate to our world. Since alchemy doesn't work in our world, he remains stuck in his dragon form.
• Hime-chan's Ribbon has Hime-chan stuck in the form of her rival, Hibino. After being hit by a truck and revived, she got better.
• Akko-chan, from Himitsu no Akko-chan, usually had to use the mirror to switch back as well, causing problems when she would temporarily misplace it.
  • In one episode of the original 1969 series, aptly named "_____", Akko-chan, upon meeting a new deaf kid, uses her mirror, out of curiosity and compassion, to transform herself into a deaf-mute version of herself. Too bad that, since the mirror works by clear utterances of the needed transformation, and since Akko-chan insisted on the "mute" part of her ailment, Akko-chan couldn't ask the mirror to be changed back anymore. The mirror itself eventually reverses her condition once she's learned not to treat deafness so lightly.
• This happens to the Macross in The Movie adaptation of Super Dimension Fortress Macross, Macross: Do You Remember Love?: when a Meltrandi attack blows off its Vertical Mecha Fins, the Macross is locked into Humongous Mecha mode since those fins, aside from being its Wave-Motion Gun, also happen to be the ship mode's forward section. And indeed after the final battle of both the movie and the series, the Macross never transforms into ship mode ever again as it's stuck waist down in a lake.
• Marvelous Melmo has two chief examples of this trope. Melmo, the titular heroine, is gifted by her dead mother with two types of candies. The blue candies make her older, and the red ones make her younger, with the explicit purpose of making her able to care for her younger siblings. As early as the first episodes, Melmo discovers that by taking both pills at once, she can de-age herself to embryonic state, then regrow her body in another form, thus shapeshifting to another animal.
  • When his little brother Totoo tries that for himself, he turns himself into a frog, spending half the series figuring how to swallow a couple of pills that now are bigger than his own stomach.
  • When the angels responsible for Melmo's empowering decide that she's abusing it, by continuously aging and shapeshifting for personal reasons, they withhold their blessing from the candies. However, at the very same moment, Melmo is currently transformed into a dog, so, without her candies, she's stuck in that form, and unable to care for her little brothers. Upon getting her Aesop, she's turned back, but this time with a limited supply of candies.
• Downplayed in Miss Kobayashi's Dragon Maid. Ilulu is fully capable of assuming her true form as well as changing her human guise, but she isn't very good at finer control of her shapeshifting, so she ends up looking like a petite girl with ridiculous breasts, Pointed Ears, and dragon claws, which is the best she can manage (though she improves enough to form proper hands later on). Tohru states that if she relaxes her control her boobs would get bigger, but would presumably end up with more inhuman features in turn. Thus, she basically has to stay the way she is now to fit in until she can get better control of her shape.
• Ranma ½:
  • The goal of the cursed characters is to be cursed again in the Spring of the Drowned Man or Drowned Girl. That way, when splashed with cold water, they'll turn into themselves, effectively not changing. Aside from that, the more common disadvantageous type of Mode Lock appears a few times as well:
  • In an early story, Ranma was the victim of a Pressure Point attack called the Full Body Cat's Tongue, which made him unable to bear hot water — the trigger to turn him male — thereby locking him into his girl mode until the cure was found. In at least the anime version, this resulted in a Twisted-Knee Collapse once Cologne told him about it, and vowed he would be cured if only he agreed to honor his engagement to Shampoo.
  • A sort of de facto mode lock occurs when Ranma pretends to be Picolet de Chardin's fiancee. Girl Ranma is locked into a tight corset made of steel, which is too tight for him to breathe in if he changes to his larger male form.
  • In the manga's Musk Dynasty arc, Herb has the same curse as Ranma and has been locked into cursed form by the water from a magical pail. He comes to Japan looking for the cure, is angered when Ranma discovers his changed body, and uses the pail on Ranma as well. Mousse and Ryoga go with Ranma planning to use it on themselves while in human form to effectively remove the curse, but just end up also stuck in cursed form. It's not clarified if the Pail always locks the affected into cursed form or if the duo simply didn't realize they needed to use hot water—either way, the Pail disappears shortly after.
  • Ranma also briefly had a temporary cure when he got a fever so hot it made any water he came in contact with too warm to activate the curse. Conversely, when he got a freezing cold later in the same story, the moisture in the air flash-froze in contact with him, which also made it impossible to turn into a girl (since solid ice doesn't trigger the curse).
  • In the second movie, Nihao My Concubine, the villain has waters from a sacred spring that transformed the one splashed in it permanently into a man. He uses it to threaten girls to come along quietly with him, but the curse spring victims try to use it to break their curse. By the end of the movie, Ranma's falling high speed toward the spring, but he has Akane falling with him, so he destroys the spring so she doesn't get stuck as a man, ruining his chance to break the curse once again.
• The Rising of the Shield Hero: In episode 13, Motoyasu puts a magic shackle on Filo's ankle that forces her to return to her human form and prevents her from shape shifting. It didn't take away any of her other powers, like her Super-Strength, which she uses to kick Motoyashu's ass and escape. Afterwards, Naofumi is able to remove the shackle.
• Happens to Moka in Rosario + Vampire when she is unable to reattach her rosary and return to her "outer" personality. It takes more than a dozen chapters for this to get fixed, and it's still hinted that the two personalities are slowly becoming one.
  • Technically, before she met Tsukune, the only one who can safely remove her rosary, she was mode-locked as her "outer" self.
• In SD Gundam Force, Captain is stuck in vehicle mode after his soul drive is stolen.
• In Suite Pretty Cure ♪, after performing a Heel–Face Turn to save her childhood friend Hummy, Siren appears to be eternally stuck in her human form, Ellen.
• In Super Pig, Buurin gets this in the second to the last episode after revealing her secret to her classmates. Fortunately for her, after collecting 108 pearls, she gets better.
• Happens twice in Those Who Hunt Elves - once involving a shape-change spell, once involving a lycanthrope. In both cases, having a spell segment imprinted on one's body creates a Mode Lock as long as the segment is in place.
• When Ichigo first turns into a full cat in Tokyo Mew Mew, both she and Mission Control fear that it'll be permanent. However, she figures out how to change back after a long and grueling day as a helpless kitten.
  • Said Mission Control, Ryou, who himself has a cat form named Alto is specifically said to be able to stay in cat form for no more than ten minutes - or else the transformation will become permanent.
• In To the Abandoned Sacred Beasts, the Incarnates are Super Soldiers who could transform themselves into mythological monsters. Many of them have lost the ability to change back, leaving them stuck in their monster forms.
• Keiki from The Twelve Kingdoms is mode-locked in his beast form per orders of The Evil Princess Joei, as a part of her plan to usurp Youko's throne. She does so because, in beast form, Keiki can't either speak to others (to let them know that Joei is not the rightful heiress to the Kei throne), nor show that he's physically unable to kneel in front of Joei (since having a kirin kneel in front of a prospect King/Queen is the proof of said King/Queen's worth). Youko manages to release him.

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