Carrion Stalker

Carrion Stalker
A carrion stalker begins life as a pale larva that infests a corpse. Over the course of weeks, this grub burrows, feeds, and grows, ultimately developing into a chitinous mass of pincers and tentacles. When an adult carrion stalker detects movement, it bursts from its corpse-cradle to attack, intent on implanting its young into the living and starting its species' life cycle anew.
More than one necromancer has animated a corpse infested with carrion stalker larvae. While this can prove shocking and deadly, some depraved spellcasters cultivate carrion stalkers within zombies. The embedded carrion stalkers ride along in their freshly animated conveyances, bursting forth once they detect living creatures nearby. This destroys the zombie, but unleashes a new horror.
Carrion stalkers also enjoy symbiotic relationships with carrion crawlers. Carrion crawlers won't devour bodies infested by carrion stalkers, but they often pick up stalker larvae as they root among filth. The crawlers then spread these grubs, potentially infecting whole sewers, graveyards, or battlefields with carrion stalkers. In return, carrion stalkers avoid preying on carrion crawlers.