An Adrastus Bolt Caliver is a unique Combi-Weapon of relic technology utilised exclusively by the forces of the Legio Custodes, the elite bodyguard of the Emperor of Mankind. Developed as a hybrid of later pattern Imperium Bolter weapon designs and Dark Age of Technology "Adrastite" directed energy beam weapons prohibited from general Great Crusade issue, the Adrastus Bolt Caliver is a potent shoulder arm serving as a portable heavy weapon for the Adeptus Custodes.
This combination weapon is able to unleash a fusillade of explosive rounds at long range with the potency of the Heavy Bolters carried by the Adeptus Astartes, or at shorter ranges fire a directed energy disintegration beam able to rip a target apart at a molecular level, causing its victims to cease to exist in a howling flare of energy.
- The Horus Heresy - Book Seven: Inferno (Forge World Series) by Alan Bligh, pg. 245