Shapeshifter Baggage / Literature

• Originally in Animorphs, the size/mass changing was essentially handwaved by explaining that a character's DNA is "rebooted" every time they transform. But in a later book, Ax explains that morpher's extra mass is stored in a pocket universe when s/he is in a smaller form, or taken from there when in a larger form... which also happens to be the hyperspace bypass that starships use. He even points out that the extra mass has to go somewhere. There's a Million to One Chance of having one's stored extra body mass run over by a random spaceship. Needless to say, the Animorphs are less than thrilled with this info. This actually happens in one book, whereupon the main characters (who were mosquitoes at the time) connected to that mass are "slingshotted" onto the ship... and take several minutes to put themselves back into one piece. With disgusting results for the onlookers. (The Animorphs aren't too interested in hearing about how they rewrote the Andalite science textbooks.) But though we learned where the extra mass goes with smaller morphs, just where the extra tonnage comes from when you go from teen to T-Rex remains a mystery.
  • Played straight, however, with the Helmacron "shrink ray". Animorphs and Yeerks are shrunken and unshrunken with impunity, without even a Hand Wave as explanation.
    • The Shrink ray technology came from manipulating the morphing cube that gave the kids their powers. So presumably the Helmacrons used the same pocket dimension mass swapping technology just for a permanent shrinking effect instead of a temporary morphing one.
• In Brandon Mull's series "Beyonders", there is a shapeshifter with a limited amount of mass. To kill it, one must cut pieces off until it becomes small enough to be ignored. The shapeshifter mentions it uses copious amounts of internal body armor if it needs to disguise its mass.
• Books of the Raksura: The titular Draconic Humanoids can shift into a normal human form, whatever their original size; the extra mass is assumed to go wherever their human clothes go when they shift back. Stone, who's been growing for centuries, has to jump off an airship deck before shifting so the mass of his 60-yard wingspan doesn't founder it.
• In Vicki Ann Heydron's short story "Cat Tale", a woman's idle wish to know what it's like to be a cat is granted; while she was thinking of a housecat, she's amused to realize that conservation of mass has made her a mountain cat.
• Katherine Kerr's Deverry series, despite being magic based, required Dweomer workers who change shape to retain their mass. Making them quite large birds.
• This is averted in some Discworld books, being first mentioned as early as Equal Rites when Esk doubts that Granny Weatherwax can turn into animals because "If she turned herself into a fox what would happen to all the bits that wouldn’t fit?" Similarly, in The Wee Free Men, a character who has been transformed into a toad wonders, "what happened to the rest of me?" In the next Tiffany book, we learn exactly what happens and it ain't pretty. If a witch turns someone into a frog, they actually turn them into a frog and a large amorphous free-floating blob of chemicals. In other books this doesn't happen, though. Essentially the Shapeshifter Baggage question raises a conflict between two fundamental Discworld laws: the Law of Narrative Causality (which says it should work like it does in stories) and the Law of Conservation of Reality (which says it can't be that simple). It's also possible that it depends on how the shapeshifting occurs; "natural" shapeshifting and Forced Transformation via mental tricks and morphic fields have "neater" results than using magic to directly warp someone's shape. In addition, the witch who had to deal with the baggage had a lot of raw power but no relevant training, while the cleaner ones are done by some of the most powerful wizards in the world or by the use of Fairy Godmother wands (which are mysterious artifacts that bypass or ignore all the usual magic rules).
  • Like most things in Discworld, Rule of Funny takes precedence, followed by Rule of Cool. Greebo the cat is a large cat, as cats go, but his human version is specifically described as being six feet tall and muscular, because the plot clearly requires it.
  • Vampires don't have to follow mass conservation rules, but they find it easier to turn into many bats rather than a single bat, especially if they've been off human blood for a while. And because the Discworld's Genre Savvy universe understands what Fanservice means, male vampires can shapeshift with their clothing, while female vampires can't.
  • It isn't stated that Angua is a similar mass in either form but the differential isn't huge — about 25% — so a short human woman would weigh about 50kg and a male wolf up to 45kg.
• Featured regularly in Jim Butcher's The Dresden Files. Conservation of mass isn't a problem at all for magical shapeshifting thanks to ectoplasm. When a creature shapeshifts, or when something from the Nevernever (faerieland) comes to the real world, the matter (in the case of a shapeshifter, the extra mass layered over their real body; in case of a demon, their whole physical body in the real world) is formed out of ectoplasm from another dimension, animated and given substance by magic. When that magic is withdrawn, the ectoplasm turns into an equal mass of a inert, clear, viscous goop which is an inconvenient mess but quickly evaporates. Arguably justified, in that there's an explanation of and consistent rules for where extra mass comes from that make as much sense as anything else in the series: leftover ectoplasm has been used to identify a crime scene as magical in nature, and I'm sure that characters have slipped and fallen on the stuff at some point or other.
  • This doesn't seem to explain how shapeshifting into something smaller works, though. Where does the extra mass go? The Nevernever? If so, how is it protected from some nasty spider-goblin thing that probably wants to eat it?
    • According to the official RPG, that's exactly what happens. It's presumably sent to something like a Demesne: a small pocket of the Nevernever under the way of a specific being, which is generally hard to reach unintentionally, as well as uninhabited by anything else. The margin notes from Harry and friends specifically mention this as a good adventure hook.
• In Expiration Date, a fugitive ghost is briefly able to disguise the body it's inhabiting by adding biomass to increase the body's height and shape. The question of where the extra biomass comes from is addressed, and it's not pleasant: it's taken from the dog that was hunting them, which does not survive the process.
• In the Fafhrd and Gray Mouser novel The Swords of Lankhmar by Fritz Leiber, a shrinking potion does, in fact, displace mass, as the now rat-sized Mouser has to swim his way out of a good-sized puddle of meat, cloth fibers, and metal fragments (flesh, clothes, armor, and weapons). Later, he grows back to his full size away from that puddle, and the mass is taken from nearby objects (and people!), notably a very fat girl who finds herself suddenly slim. Great news for her, Squick for Mouser?
• Garrett, P.I.: In Petty Pewter Gods, the flying horses' torsos slim down drastically when their wings sprout via shapechanging, and plump up again when they retract them after landing.
• Handwaved in The Half Blood Chronicles, by Mercedes Lackey and Andre Norton. Dragons shapeshifting to a smaller form have to shunt their extra mass into an extraplanar space they call the Out. A dragon in human form, when viewed in the magical spectrum, can be seen as a human surrounded by a dragony "shadow". This shunting also takes a certain level of skill on the dragon's part. Taking a form that's the same size as the dragon in question is simple. Taking a form as small as a human or elf is a challenge.
• In the Iron Druid Chronicles, this is handwaved. Magic disobeys the laws of physics all the time. It works however people believe it works. And since widespread knowledge of the laws of physics is a fairly new thing... yeah. All of the "Old Ways" disregard the laws of physics, such as a druid's shape shifting, or Coyote's resurrection.
• In the Jane Yellowrock series, by Faith Hunter, Jane is a Skin Walker, capable of copying the genetic code of animals and possibly people to assume a new form. This Native American magic allows her to sloth off mass and store it 'else-where' (mainly stones and sand) and to gain mass to grow in size. Interestingly enough Jane likes to only absorb or deposits mass into stone because to her it doesn't have any individual traits aside from being empty matter.
• Explicitly averted in the Kitty Norville novels. The easiest way to distinguish a werewolf in lupine form from its mundane counterpart is the fact that they are normally at least half again as large as the 36 kg (80 lbs) norm.
• Dragons from Kroniki Drugiego Kręgu need a "pattern" for the specific organism to shapeshift into, as well as loads of additional energy — huge amounts of meat, in other words. Or soil. Or at least apples, though carnivorous dragons think these are yucky.
• In Liar (2009) by Justine Larbalestier this is explicitly averted; werewolves are exactly the same mass in both forms.
• In Loyal Enemies, there's no explanation given for where the dragon Gloom's mass goes when he changes forms between dragon and human, despite being horse-sized as a dragon and an average human in size, respectively.
• Steven Erikson's Malazan Book of the Fallen has this feature for both Soletaken and D'ivers (single- and multiform shapeshifters, respectively). Depending on which one of these beings you encounter, you might be up against a grown man who can become a hawk and fly away... Or something that can become one or more dragons. At least the undead shapeshifter can't become living...
• In Frank Herbert's novel Man of Two Worlds, a shapeshifting alien is captured by humans and is confined to a cell with only a small drain being the way out. He laments the fact that he can't simply destroy his own mass so that he can become small enough to fit through the drain. Too late does he realize that he could have just turned into a snake and slithered down the drain, without having to bypass the law of conservation of mass/energy.
• The kandra of Mistborn: The Original Trilogy explicitly are bound by Conservation Of Mass. This comes up a couple of times in the third book, including one where the hero takes advantage of the fact that the same body mass that makes for a scrawny human makes a fairly beefy wolfhound and one where the same hero quickly shifts up from dog to horse by eating an entire pig for the extra mass. Normally, however, this isn't a problem for them, as they have to digest their target to produce an exact imitation, which, by definition, gives them enough mass to transform.
• Goes all over the place in the Mercy Thompson series. Werewolves always gain mass when they transform: a woman who's 120 pounds as a human will be more like 180 pounds as a werewolf. Adam, who's a pretty big guy when he's human, becomes an enormous werewolf. Mercy, on the other hand, is a mere thirty pounds as a coyote. She also admits to being totally baffled by how fae glamours work, as they're not exactly shapeshifting yet can still, in her words, "somehow allow a nine foot tall ogre to fit into a size four dress."
• Averted in Poul Anderson's Operation Chaos where all animal based lycanthropes must observe Conservation of Mass. The 180 pound hero transforms into an 180 pound wolf, while a Giant Mook who turns into a tiger is "seven feet tall and monstrously fat."
• Kelley Armstrong's werewolves in her The Otherworld series retain the same mass in either form, and have to eat lots to account for their higher metabolism.
• In the Perry Rhodan universe, shapeshifters with actual physical bodies of their own that they depend on generally do have to obey conservation of mass no matter how flexible they may be otherwise; the same is not necessarily true of Energy Beings taking on a physical form for their convenience, however, and given the number of handwaves involved in psi and hyperspace physics the line between the two can get a bit blurred on occasion (as it arguably does with e.g. the Cynos, who do seem to combine traits of both).
• Averted in Dean Koontz's novel Phantoms. The Big Bad monster can change its shape and detach pieces of itself, but it must obey conservation of mass. Its creations often appear outsized when it tries to imitate something too small or too be big, and it's only able to imitate a much smaller creature by splitting itself apart.
• Safehold: Merlin can change his appearance, but his mass and rough body dimensions always remain the same. The fact that all the seijins who are popping up are the exact same height and are never visibly active at the same time allows Aivah to figure out that they're all the same person.
• Averted in Sector General, where Dr. Danalta does not, in fact, lose or gain any mass when it changes shapes... so when it turns into something that looks like a teddy bear, it is still a very heavy teddy bear.
• Used and lampshaded in The Shapeshifter book series, Dax Jones can turn into a fox, but has no idea where his clothes and whatever he is carrying disappear to when he does.
• Star Wars Legends:
  • In the Galaxy of Fear series, the race known as the Shi'ido can shape-shift. It's explained that due to their extremely long lifespan, in which they can live for 500 years and only people older than 61 are considered adults (makes you wonder what their drinking age is), their shapeshifting ability improves with age. Young Shi'ido can only change skin color, older ones could change into any humanoid species they wanted, and ones even older can change into whatever. However, if they tried to change beyond their natural boundaries, they'd be stuck in that form for weeks or months. How exactly they could change isn't well explained, but The Essential Guide to Alien Species said something to the effect that they have folds of extra skin under their skin that they can use if they need to to change into larger or smaller species (or rocks and trees, apparently). Also, since some species identify others with smell as well as sight, and the Shi'ido aren't perfect at what they do, it's explained that they use telepathy to get around (what could be described as) Latex Perfection.
  • Galaxy of Fear has Hoole ignore conservation of mass whenever he needs to. If he's escaping with the child protagonists on a skimboard that won't take his extra weight, he can just turn into a small rodent that doesn't burden the craft. He once becomes a mammoth frog to carry them one at a time over a wall, and he can be a small flying animal to cover ground quickly. The times when he can't turn into something that gets him out of whatever situations he's in, so that it's the ingenuity of the kids that saves the day, sometimes seem arbitrary.
  • Clawdites, the species of the female bounty hunter in Attack of the Clones. For them to transform it requires great concentration, which was broken slightly during the speeder chase with Anakin, and they are incapable of changing mass significantly. The RPG expansion that introduces Clawdites as a playable race notes that their shapeshifting ability is fluid-based, and that some individuals use a specially-built saline pump on their person to increase or decrease their mass. Even then, however, growing or shrinking beyond the size of an average humanoid is out of the question.
• The Stormlight Archive: The singers are capable of shifting between forms by bonding any of several spren, and these forms can have notably different sizes and builds. For example, a singer can shift between dullform (a little shorter than the average human, and not incredibly bulky) to warform (at least a foot taller, and a lot more heavily muscled), with no explanation given as to where the extra biomass comes from. Or where it goes if he shifts from warform back down to dullform, for that matter.
• Tofu from Super Minion does obey conservation of mass, and on top of that he also needs a lot food to power his shapeshifting. His solution is to use ultra-dense muscles so that he can weigh over three hundred pounds while still looking like an unremarkable 18-year-old. For a while, his obsession with stockpiling energy gets so bad that it actually starts to slow him down.
• The Timeweb trilogy by Brian Herbert takes the more obvious approach: shapeshifters grow larger by absorbing rocks and dirt into their own mass. Growing smaller is somewhat like shedding snakeskin, and can be a bit disgusting if a massive change is needed.
• In Sheri S. Tepper's The True Game series, shapeshifters can increase their mass by incorporating additional organic material (Mavin uses a sack of grain at one point); when they decrease their mass the excess is expelled, resulting in what looks very like a pile of minced beef.
• In Void City, vampires have the power to shapeshift into one or more animals, but how it works varies between individuals. Some are able to take their clothes with them, while others have to leave their clothes behind. Eric actually generates new clothing: even if he starts out naked, he'll be in his usual casual clothes when he changes back. As a result, he's accumulated tons of identical outfits. Everyone just accepts it as a natural part and parcel of a vampire's magic powers.
• Warbreaker: Members of the Idrian royal family can change the color and length of their hair, but growing hair more quickly consumes nutrients from elsewhere in their body.
• Harry Turtledove not only keeps to the principle (illustrated distinctly by a couple werehawks too heavy to fly) in Werenight, he gives Poul Anderson's Giant Mook a semi-affectionate nod... and upgrade. An "immensely tall, immensely fat" barbarian chief turns into a sabretooth. A big sabretooth.
• Averted in the Wild Cards series, where Kid Dinosaur can change shape into any kind of dinosaur, but explicitly does not change mass. This results in such things as a 3 foot tall T-Rex.
  • Played straight with another character who's body stored everything he ate (he never had to go to the bathroom) and kept absorbing until he had enough mass and excess food to go into a prolonged hibernation, during which his body would radically change (as would his powers).
  • Skewed with Rahda "Elephant Girl" O'Reilly, who is a Irish-Hindu were-elephant. Her excuse is that she absorbs energy from the environment and converts it into mass; this can black out a city if used in the right location. Likewise, when she changes back the excess mass converts into a flash of light. Of course, the amount of energy needed to convert into a couple of tons of elephant flesh is incredibly titanic; and the energy release from changing back should wipe out a continent. So it's neither averted nor played straight.
• The novelization of the 2010 Wolfman movie makes note of the extra mass Lawrence gains when transforming into a werewolf, and suggests its source is hell itself.
• In Is It Wrong to Try to Pick Up Girls in a Dungeon?, Lili's transformation magic, Cinder Ella, is limited to people around the same size as her. As a result, she can only transform into small humans, dwarves, chientropes, and other pallums.
• Addressed in The Magicians when the students learn Voluntary Shapeshifting; the biggest hurdle for mastering the process of transforming from a human into a goose is in learning how to correctly shed the body mass and magically store it away, then reapplying it during the return to human form.
• In Camouflage, the Changeling has to acquire new mass in order to take on larger forms, most often by absorbing it from corpses. By contrast, it can easily shrink by simply discarding its old mass, though such drastic changes to its body take several painful minutes at the very least.

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