A polymorph is a shape-shifting organism that can change into anything it pleases, seen in the series III episode "Polymorph" (1989). It survives by draining a person of a negative emotion. It is described in the episode as being designed to be the perfect warrior, blending into any background, causing confusion and disarray amongst the enemy by playing with their emotions, but the creature mutated into something terrifying and insane its creators couldn't control. One of the polymorph's forms appears somewhat similar to the Xenomorph Alien from the movie "Alien" (1979). Polymorphs appear to be able to drain emotions from mechanoids and holograms, and are able to physically touch soft-light holograms. A genetic mutant documentary in "Can of Worms" mentions that a female polymorph deposits a passing organism with her eggs while disguising herself as a mate. Kryten also explains that these eggs hatch soon after the host body for them is found and that polymorphs often die after this exhaustive process is complete, ending their life cycle.