Cadaver Collector

Cadaver Collector
Cadaver collectors cannot summon specters of those they have not slain, nor will slain specters return to one. Starve it of victims, and then do not attack until you can be sure you'll destroy it. Meteor swarm works well.
Cadaver Collector
The ancient war machines known as cadaver collectors lumber aimlessly across the blasted plains of Acheron until they are called upon by a necromancer, hobgoblin general, or other evil warlord to bolster the ranks of a conquering army. These fearsome constructs obey their summoners until being dismissed back to Acheron, but if a summoner comes to a bad end, a cadaver collector might wander the Material Plane for centuries, collecting corpses while searching for a way to return home.
Sweeping the Dead
Cadaver collectors respond to a summons from a mortal only when they are called to the scene of a great battle—either where one is in progress, where one is imminent, or where one once took place. They encase themselves in the armor and weapons of fallen warriors and impale the corpses of those warriors on the lances and other weapons embedded in their salvaged armor.
Conjured Berserkers
Corpses that accumulate on the construct's shell aren't just grisly battle trophies. A cadaver collector can summon the spirits of these cadavers to join battle with its enemies and to paralyze more creatures for eventual impalement. Although these specters are individually weak, a cadaver collector can call up an almost endless supply of them, if given time.
Constructed Nature
A cadaver collector doesn't require air, food, drink, or sleep.