Shapeshifter Baggage / Western Animation

• Jake from Adventure Time is an extreme example, being able to stretch to Attack of the 50-Foot Whatever-scale on demand. One episode, "The Limit", explored what limit there is to Jake's shapeshifting, and he didn't reach it until he had stretched a great distance. But that was due to his organs no longer functioning, so the hypothetical limit of how massive he can become hasn't been explored yet.
• Ben 10 justifies this with the Omni/Ultimatrix being the source of all Ben's added and lost mass.
• CatDog isn't even a shapeshifter, but they can still stretch over miles and miles with no loss of volume when, normally, their body is just a few feet long.
• The Chip 'n Dale: Rescue Rangers episode "Dale Beside Himself" features the Fleeblebroxians, a roughly mouse-sized alien race that can transform into anything with ease, for example a dragon the size of a small dog and several hundred times the mass of a chipmunk. This can hardly be explained by the fact that they consist of "unstable molecules".
• Costume Quest (2019): The monsters use magic-powered human suits that ignore mass entirely. A brute-class monster immediately compresses and loses weight, while the kids and grubbins grow to fit the arms and legs.
  Wren: Nothing makes sense anymore.
• On The Fairly OddParents!, every fairy suffers from this. Let's just say "A Wizard Did It" and move on. As these are the same fairies that regularly POOF! things into existence the baggage is one of the least egregious things about them.
• On Gargoyles, sequences in which gargoyles awaken from "stone sleep" often show fragments of stone scattering from their skin as they re-animate, as if they're breaking out of a very thin coating of rock. Although there's plenty of magic in their Verse, "stone sleep" is described as a natural physiological quirk of their species, so losing an outer crust of stone every sunset ought to cost them whatever energy they'd allegedly accumulated from sunlight while immobile.
• Handwaved in Generator Rex with nanobots. Not always a perfect solution there, though: nanites build stuff out of other stuff, so constantly generating his weaponry and vehicles, and doing it again when they get broken, means a lot of metal is being made from no apparent source; much more of it than Rex's body and nanites could possibly provide the material for. The plot of one of the episodes deals with another type of shapeshifter baggage: where do all the nanites Rex absorbs go? It turns out that every now and then Rex has to go to a base in the Antarctic with giant, massive vats he has them drained into, otherwise the sheer quantity may make him go crazy.
  • A quick moment in one episode had someone attempting to retrieve him from the ocean being dragged down carrying Rex until he retracted his giant metal fist, which raises so many questions then and there.
• Nobody's really sure where Kaeloo gets her extra mass when she transforms. Interestingly, Mr. Cat, the other shapeshifter in the cast, doesn't appear to experience significant changes in mass despite his wide variety of forms.
• Discussed in Kipo and the Age of Wonderbeasts, where Kipo hysterically rants about her newly discovered half-Mute abilities. And this is before she discovers she can perform even more drastic limb shifting, such as turning her arm into a giant leopard leg:
  Kipo: I mean, my dad told me about "body changes", but nothing like this. I have fur that grows out of my arm, then goes away! WHERE DOES IT GO?
• In My Little Pony: Friendship Is Magic, changelings, or at least Pharynx and Ocellus, can apparently transform into things much larger and heavier than themselves, with all the mass that the larger creatures would have. No explanation is given for the added mass.
• Imp from She-Ra: Princess of Power routinely took on forms that required an outside energy source to perform their function (and more energy than he could reasonably produce naturally) and he was never shown having to recoup what was lost. Notable examples are being a lit candle, two types of rocket complete with jet propulsion, flame thrower powerful enough to start a forest fire, and a laser rifle.
• Mostly averted in The Spectacular Spider-Man. Sandman loses some of his sand every time he fights, and has to be 'fed' raw silicate to keep the same mass. He only becomes bigger when he ingests more silicate, and becomes a giant after taking an entire beach's sand.
• Gems in Steven Universe can shapeshift into just about anything with their Hard Light bodies, but as Amethyst tells Steven when he tries to make himself taller, they can't keep their forms for too long or it'll make them worn out. As Steven is half-human, this ends up turning him into a baby until the following morning.
  • In a later episode, when Amethyst has to impersonate Jasper, she soon starts sweating from having to hold a larger form for so long, and changes back as soon as the Rubies who were looking for Jasper aren't looking at her.
  • Out of all the known Gems in the show, Pink Diamond is the only one shown to easily shapeshift into a form much smaller than her without any complications, more specifically as Rose Quartz. Possibly justified because she was taller but significantly thinner as Pink Diamond, and so her mass as the shorter, fatter Rose was most likely similar - or maybe it's just Diamond mojo.
• Challenge of the Super Friends never explained where Apache Chief got the mass to grow 50 feet tall whenever he said "Inekchok!". People speculated that 500 cattle disappeared from the Great Plains whenever he did this. Clearly, this is ridiculous — everyone knows that a Native American would absorb 500 buffalo, not 500 cattle!
• In Teen Titans Beast Boy has been everything from an amoeba to a Diplodocus, yet his base form couldn't weigh much more than 100 pounds. The same likely applies to his comic form. Beast Boy often uses this trope to his advantage. A typical move for him is getting up high with a small bird morph, then becoming an elephant or dinosaur to smash whatever's below him. Then there's his "patented wet-willy manouver", that is he turned in a small bird, flew inside the ear of the gigantic Trigon and then turned into a whale...
• X-Men: Evolution's Mystique, unlike her comics counterpart, is not limited by her mass, regularly transforming into a raven and flying away.
• Beast Boy uses similar physics-defying tactics in Young Justice where he'll transform into a fast running or high jumping quick animal like a cheetah or monkey, get some serious speed or height, and then transform into a rhino or elephant to slam into them with all that extra weight moving at that momentum.
  • In the Young Justice Season 3 episode "Nightmare Monkeys", this is brought up by the Monkey God when he reveals the he had chosen Gar to receive his powers.
  "Why do you think you can only change into animals? And do the words 'conservation of mass' mean anything to you at all?"
• In Transformers, extra mass is stored in pocket universes. Oddly enough, the parts of someone's alternate mode that don't really have anything to do in robot mode don't go away, and instead tend to form decorative "kibble". This technique is used mainly for changing size and storing weapons.
  • The 2007 movie specifically averted this by having the CGI computers track where every nut and bolt went during transformation. The result was that some robot forms were twice as tall as others. (The Allspark was the main exception; presumably being the Macguffin gives you the right.)
  • The original cartoon did not explain where, for example, Optimus Prime's trailer went when he transformed from truck mode - it's just shown going out of shot or into the frame as required. (The trailer is supposed to turn into a battle platform, but frequently this was either ignored or forgotten.) This has become a long-running joke in the fandom, and even appeared in a Transformers: Animated short, where a kid asks Optimus where his trailer goes. As it turns out, Optimus doesn't know himself.
  • There was, in fact, one episode of the G1 cartoon where, as Optimus transformed and his trailer started to move offscreen, it actually glowed briefly, then vanishes. Which becomes funny as in one incarnation, the trailer served as a holder (or whatever) for a pair of secondary robots. In the film series, it actually holds Optimus' spare guns. Lots and lots of spare guns.
  • In the IDW comics (the "-ation" miniseries at least) mass shifting, as befitting dimensional rupturing, required a lot of energy to do and generated quite spectacular fireworks due to laws of physics being broken. The headache was simultaneously decreased and increased by only having one character consistently mass-shift, but of course it was Megatron turning into a gun.

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