Also known as: ブラックバレル
Black Barrel is one of the Seven Superweapons of Atlas, one of seven weapons developed and kept by Atlas of the Mage's Association.
The gun is a "Conceptual Weapon of natural life-span", capable of imposing the notion of limited life-span into the body of near-immortal creatures. Composed of True Ether, bullets fired from the gun will disintegrate all instances of Grain and Ether they come into contact with, ignoring any parameters of beings that intake either substance to deliver direct damage.