Cranium Malevolus

This iron-clad death's head was once a servo-skull taken from the Sainted Halls of Terra. Though intended as little more than a trophy, under the ownership of the Iron Warriors it has mutated into a mouthpiece for the mind-shattering language of the soul forges. The coded blurts of Dark Tongue it emits are potent enough to undo the machine spirits of enemy technology. Its scrapcode chant is so maddening that opposing war engines will spontaneously immolate themselves in order to avoid spending another second near the floating, anarchic device.