Necromorph

Overview
The Necromorph is a parasitic mutagenic being. It must wait for the the host creature to die before mutation can begin, as the body's immune system will absorb the creature before it can do any damage. The mutated being must be mauled in a variety of ways to kill it, as some will shrug off losing a limb and adapt, but die upon decapitation, others vice-versa. Others must be sliced in two, or have their egg sac removed.

Behind the Scenes

 * Their name comes from the Greek words Necros (corpse) and morph (change), literally "corpse changer".