Size Changing/Anime and Manga

* Anime in general tend to have this when people "go chibi"; that is, their bodies shrink down smaller than their heads.
* Attack on Titan: Eren Yaeger turns into a Titan when he bites his thumb.
* Bakugan can do this, but only in the anime. The tie-in toys only transform a la Transformers, and little else.
* The Big Card of Cardcaptor Sakura can do this to those affected.
* Cyborg 009 used this *twice*: Once in the original manga, once in an anime-only story from the 1968 anime.
	+ Though in the anime's case, it was three people (all three of them criminals) who most likely permanently became giant and met their end on the island that blew up towards the end of the episode.
* Danganronpa: Nagito Komaeda accidentally turned his dog into a giant, thanks to a mix-up between Seiko Kimura and Ruruka Ando. He still considered himself fortunate as his then-giant dog caused Seiko and Ruruka to trigger a mass explosion throughout the building the examiners were in. To quote Chisa Yukizome, "This is so bad. Extremely."
	+ This instance also happened to be plot-related, as it somehow kick-started Junko Enoshima's plan to take down Hope's Peak.
* Digimon plays with this a lot of times.
* The result of one variant of Time Shifter in Flint the Time Detective.
* Fullmetal Alchemist and Fullmetal Alchemist: Brotherhood had Alphonse Elric appear larger in his suit of armor, but he didn't grow at all: his brother Edward bonded his soul to that armor, costing Edward his arm in the process.
	+ Edward Elric can turn his metal arm into a giant weapon, but the arm/weapon gets thinner when that happens, due to the Law of Equivalent Exchange.
	+ Apparently, "Father" can make a flower grow giant and turn inorganic through a Philosopher's Stone. Edward and Alphonse lampshaded that he shouldn't be able to. Since "Father" takes on many forms, once the real stone was destroyed, his final human form was shrunken down to nothing (or more accurately sent away from Earth) and his first form was sent to the Gate of Truth.
* Galaxy Angel did this several times:
	+ In *Galaxy Angel Z*, all of the Angel Brigade except Normad turns giant due to lost technology.
	+ Also happens in *Galaxy Angel A/AA*. Between the Colonel being shrunken down in shame, Mint trying to make Normad giant, both the Colonel and the Major becoming giant using the Won Bat...
	+ In fact, a lot of lost technology is capable of doing this. It's just as often the lost technology of the episode would make something bigger or smaller as it is putting lives in peril. Sometimes even *both*.
* Towards the end of Gurren Lagann, this does not happen to any specific person, but rather a drill. Until its size is comparable to the universe. "Pierce the Heavens", indeed.
* In Hi-sCoool! SeHa Girls, during the girls' Space Channel 5 mission, one of the Virtua Fighter characters that showed up became giant. It ended up useless anyway, since Saturn defeated the final boss... and proceeded to be denied any medals because of "using sex appeal to gain ratings".
* Himouto! Umaru-chan: The above-mentioned entry where people can invoke this by "going chibi"? If Umaru does this, this *sticks* unless she goes outside due to this smaller form not being afraid to hide her true nature as an otaku. Or her obsession with potato chips and cola, apparently.
	+ This can also happen with the other girls from the series in *Himouto! Umaru-chanS*. The manga (and 22-minute anime seasons)? Not so much.
* Inuyasha has Kirara, who is usually small and cute. However, when he grows larger, he also grows fangs. Notable in that said Size Changing is usually preceded by Kirara being engulfed in flames.
	+ The larger form does have a purpose- it's used whenever Kirara has to transport Inuyasha (and Kagome, and the others) somewhere else.
* It's rare to see this in JoJo's Bizarre Adventure, but *Stardust Crusaders* (yes, the arc that introduced Stands to the franchise) has this happen significantly to Iggy during and after his fight with Pet Shop.
* Kill la Kill: Ragyo Kiryuin appeared giant during the final battle... until her daughter Ryuko absorbed most, if not all, of her Life Fibers.
	+ Ryuko can even turn the Scissor Blades into gigantic ones with "Alumni Mode".
	+ Ira Gamagoori's only set size is "bigger than you", so this happens to him a lot.
* *Medabots* owners can make their Medabots look bigger with the use of larger Medaparts. Otherwise averted.
* In My Hero Academia, Mount Lady can turn into a towering giantess using her Quirk.
	+ There also exists a Quirk called "Size", which alters the size of things.
* One ability of the Akimichi clan in Naruto.
* The essence of Luffy's Gear Third of One Piece. He *does* shrink down after exhausting it, though.
* One-Punch Man has plenty of characters that change size (almost the entirety in the Super Evil position), but their lives are still ended by *one punch*.
	+ Saitama subverts this. Despite three *years* worth of training, he's about the same build (and size) as he was three years ago. The only difference was he went bald and gained super strength.
* My Melody's magic (aka "Melody Mark") can often make certain objects change size, usually with an "Onegai?" first. This is usually more of a last resort then anything else.
* Panty and Stocking with Garterbelt has Stocking turn into a 20-foot giant in one episode.
* Pokémon has Giant Pokémon, Pokémon which are much larger than usual.
	+ Giant Pokémon can also become defictionalized (while not using this trope, considering this trope cannot apply to real life due to the Square-Cube law): a giant Pikachu plush/bed, the world's largest Pokémon plush, exists.
* The Powerpuff Girls Z version of HIM shrinks down whenever he gets cold. Conversely, he grows giant with black Z-rays.
	+ Also, Negatron, Ken Utonium, and a duck become giant in separate episodes.
* Puella Magi Madoka Magica: Apparently every Magical Girl who lost all hope turns into a witch much larger than their magical girl forms (...mostly; Charlotte is an exception).
	+ And when Madoka wished for all witches to cease existing in every timeline? She grew giant wings, a direct consequence of her becoming a god/the embodiment of hope.
* The manga version of Ranma ½ has Ranma metaphorically shrinking after he felt guilty about something. And this was boy Ranma, to boot.
	+ The Cursed Springs have this ability depending on who first drowned in the spring. To put it simply, when splashed with cold water, this is averted with Ranma, who gets hit with another trope instead, downplayed with his father, who turns into a panda (which, according to the character designs, aren't much bigger than humans anyway), and played straight with Shampoo, who turns into a cat (and shrinks down to fit her cat form). The changes are, naturally, reversed when they come into contact with hot water.
* Sanrio has some works that use this trope:
	+ In Show by Rock!!, getting into animal form also meant being shrunken down into a chibi.
	+ Jewelpet: *Magical Change* has a Jewelpet's human form be taller than the actual Jewelpet by his/herself. This is justified, though.
		- The main pets have become giant at least *once* throughout the anime. Ruby herself has done this twice.
		- Early in the *Twinkle* season, three Jewelpets became giant thanks to Sara's magic (Akari and Ruby ended up making it worse, shrinking themselves in the process).
	+ In *Rilu Rilu Fairilu*, Lip turns into a dragon. You heard that right- a tiny Fairilu once turned into a giant dragon.
	+ Go-chan is usually advertised as being "five times taller than a TV set". In the movies, Go-chan's nowhere near that size.
		- According to the above statement, Go-chan's size can fluctuate due to larger and larger TVs coming on the market. By the time TV Asahi eventually retires the mascot, he'll have had only one set size: bigger than you.
* Servamp: Justified, since they often change from animals (or talking dolls) into humanoid vampires. Becomes even more extreme towards the end of the anime, via Kuro's lion form.
* Shugo Chara!: Remake Honey Special, in which Amu (as Amulet Clover) has her whisks grow twice their size. Otherwise, it's nothing more than a more powered-up version of Remake Honey.
	+ Yaya can get a rattle that can grow to giant size when she Character Transforms.
	+ Regarding *actual* Character Transformations/Character Changes, this is averted, since aside from gaining new clothing/accessories/powers, everyone remains the same after the transformation is complete.
* Soul Eater has Excalibur. While he himself cannot turn into a giant, the sword *can* grow giant wings of light.
	+ Maka's soul increases in size after she gets stronger.
* In Ultra Maniac, episode 7 has a growing cat and a growing chameleon thanks to a potion which Maya Orihara herself considers a failure. Guess which one shrinks down at the end of the episode?
* Summoning monsters in the Yu-Gi-Oh! anime and videogames will not do this. However, if you turn them into Toons, they shrink significantly.