sentences:  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.