Metamorphosis Monster

Everything About Fiction You Never Wanted to Know.

In most cases, you can expect the child form of a creature and the adult form of a creature to be rather similar. Kittens look like cats, puppies look like dogs, etc. This isn't always the case, though, such as in certain insects that go through metamorphosis. The most obvious example is caterpillars becoming butterflies, but there are even weirder examples.

Naturally, fiction has played with the concept. It's not an uncommon occurrence for parasitic grubs to become giant lizards, or fuzzy rabbitlike creatures to grow up to become bearlike behemoths. If you weren't told they were the same creature, you never would believe it.

Naturally, the most extreme cases present a problem for artists. How do you go about creating the intermediate stage between an insect and a dragon? In many cases, they don't bother. The transitional stages are either never shown onscreen, or the creature will use a form of cocooning that prevents the audience from seeing its metamorphosis.

If the adult form is significantly stronger, this can act as a species-wide Magikarp Power, but sometimes the different forms are dangerous in different ways. While this is often used for a species-wide One-Winged Angel or to introduce more powerful forms of old enemies, occasionally it's just for weirdness' sake.

See also Metamorphosis.

Examples of Metamorphosis Monster include:


  • While on their home planet at least, the metroids in the Metroid series go from floating parasitic jellyfish to beetlelike creatures to giant armored lizards. In an interesting twist, the first stage is not only the most well-known and arguably most dangerous, but while nearly every game has a variant of the jellyfish stage, the later stages have only appeared in a handful of games. Apparently their larval stage can become mutated in various ways from the chemicals and radiation in its surroundings,[1] and they can only complete their normal life cycle on planet SR-388.
    • Also, Ridley's larva form is a small rabbit-bird-thingy, which then becomes a feathered lizard kind of creature before finally evolving into the Space Dragon we all know and love.
  • As the inspiration behind the 2 examples from Metroid above, the Aliens from Alien also have a peculiar lifecycle: It could be described as haplodiplontic, with the "gametophyte" being a creature that could be described as a mismatch of hads/legs, tail and genitalia that lives just to seek a host to impregnate, and the "sporophyte" developing in the body cavity of the host, emerging violently as a snake-like creature, and quickly growing up into a large, 4-limbed biomechanoid creature with some traits reminiscent of the host species, but taller and slimmer. If it grows into a fertile queen, it also changes its limb structure, grows an additional pair of arms, increases in size, and loses the host-like characters.
  • Quite a few Pokémon have a variant of this with their evolution. The most obvious example is Magikarp to Gyarados (Small karp to sea serpent), but there are others, such as Trapinch to Flygon (Ant lion to dragonfly/dragon) and Feebas to Milotic (fish to elegant-looking sea serpent)
  • Gremlins: The Mogwai multiply if gotten wet, and transform if fed after midnight.
  • Hedorah in Godzilla vs. Hedorah.
    • Likewise, there's Destoroyah who went from a colony of microscopic crab-things to a giant scorpion-crab thing to a giant demonic crab-thing.
    • Mothra and Battra, naturally. Both are giant caterpillars who then become giant butterflies.
  • Irys from the film Gamera 3: Revenge of Irys goes from a strange-looking yet somehow adorable snail-like creature with tons of tentacles to a giant bipedal monster with tentacles with spears on the ends, swords for arms, and a cone-shaped head with a single glowing eyeball.
  • In Sluggy Freelance Aylee has gone through this over a dozen times, eventually turning into a fifty foot tall dragon and finally into the most dangerous creature of all ... a woman!
  • Starslip features the Jinxlets. Adorable little bug creatures that gain nourishment from cuddling. When fed Royal Jelly, however, they turn into terrifying berserker engines of destruction.
  • In Series 3 of Primeval, the team encounter a nastily infectious fungus that converts its hosts into hideous mutants which of course are infectious as well.
  • A Space Ghost episode had Jan and Jayce adopt a cute l'il creature called a star fly, unaware that it was the larval form of a giant glowing Kaiju called a star beast. It grows up fast and seems threatening, but in the end, it remembers Jan and Jayce and refuses to hurt them.
  • Gosamyr, a friend of the New Mutants, was a member of an alien race whose members undergo through this. At first, they're cute, delicate, winged creatures (although with the annoying ability to empathically - and involuntarily - cause conflicts among male humans), but then they enter the cocoon phase (which lasts centuries) which would turn them into their adult form: gargantuan abominations.
  • Most officially defined evolutionary lines in Digimon fall under this; lines with a consistently maturing appearance are the minority and are generally specifically designed as protagonists of an anime series. Perhaps the standout example is Patamon of Digimon Adventure, who evolves from a vaguely-defined small orange winged mammal thing into an angel. In the broader canon, most Digimon have a wide variety of forms to which they can evolve, generally not restricted to specific lines, and so pretty much any and every Digimon can be an example of this.
  • Cell from Dragonball Z evolves from a half-insect, half-lizard monster to an humanoid android. His intermediate stage is a vaguely humanoid hulk, who for some reason lacks the wing that both his initial and final stage have.
  1. eg. exposing one to Phazon on planet Tallon IV causes it to grow long tentacles, and beta radiation will make it divide into two