|First Appearance||The Gauntlet|
Polymorphs are a species from the molten planet of Viscosia.
Polymorph's are unicellular organisms that are generally green in color, however they do come in different colors.  They are gelatinous humanoids with a pointed head and and an asymmetrical, drippy ameoba-like shape. When in humanoid form, they have four fingers on their hands.
According to Matt Wayne, he imagines Polymorphs to be scavengers, dissolving and assimilating any unclaimed organic matter. 
Powers and Abilities
Polymorphs can revert to a puddle, a shapeless mass or mimic the shape of something. Physically harming them is extremely difficult as solid objects and even energy passes through them without any damage. Their semi-liquid bodies are able to squeeze into tight spaces.
Polymorphs have strong digestive acids, which can be used as an offensive weapon, either by smothering something or releasing a sort of corrosive gas.
Polymorphs with the Anti-Gravity Projector can control it from afar and use it as a weapon.
On planets with stronger gravity, Polymorphs are tied to their Anti-Gravity Projectors and lose control of their forms if they are separated from their projectors. This has been demonstrated with Goop and Vilgax.
The Anti-Gravity Projector is not native to the Polymorph's; they are for Polymorphs that travel to planets with stronger gravity then Viscosia. The slime is normally in a humanoid shape with a pointed head, narrow eyes and spikes on their shoulders.
- The name Polymorph means "many shapes".