The Liber Daemonicum, also known as the Liber Daemonica and the Libra Daemonicus, is the Grey Knights Chapter's sacred book. Its full version contains prayers, battle rituals, litanies, funeral rites, and Chaos lore.
The Liber Daemonicum is an enduring symbol of a Grey Knight's devotion to his mission, and contains the cardinal tenets of lore culled from the dark knowledge caged within the walls of the Sanctum Sanctorum on Titan.
These gnarled tomes contain the Chapter's rites of battle and detail the traditional duties of every Grey Knight's rank. The books themselves are also potent psychic talismans in their own right, with pages illuminated in silver and bound to a spine carved from the thigh bone of a martyred saint.
While it may appear to be a normal book, opening the Liber Daemonicum will reveal a series of flickering paper-thin screens that contain interactive information that can be brought to focus or enlarged.
Page after page discusses tactics and how to fight the denizens of the Immaterium, as well as listing the True Names of a great many daemonic entities; all information collected from the Librarium Daemonica, the repository of dangerous knowledge concerning Chaos pieced together by the Ordo Malleus over the millennia.
The book's instructions pull no punches; it includes an extensive discourse of when to terminate Chaos-corrupted allies and a whole chapter discussing the moral implications and appropriate use of Exterminatus.
Every Grey Knight carries a version of the Liber Daemonicum in a beautifully decorated ceramite case on his breastplate. It contains exactly 666 words. The book is also represented in Grey Knight iconography, on the chestplate and pauldron of both power armour and Terminator Armour.
Domina Liber Daemonicum
The Domina Liber Daemonica is a relic that once belonged to the Grey Knights' first commander, Supreme Grand Master Janus, the only Grey Knight to ever master all 666 words of banishment, each one painstakingly recorded on the Domina Liber Daemonicum's pages.
In times of great need, a hero of the Chapter will carry the Domina Liber Daemonica into battle and the book's bindings crackle with arcane energy, as its words of banishment send daemons howling back into the Warp.
- Codex: Grey Knights (7th Edition) (Digital Edition), "The Relics of Titan"
- Codex Adeptus Astartes - Grey Knights (8th Edition), pg. 100
- Dark Heresy: Purge the Unclean (RPG), pg. 79
- Grey Knights (Novel) by Ben Counter
- Warhammer 40,000: Compilation (1st Edition), pg. 5
- Warhammer 40,000: Dark Millennium (2nd Edition Boxed Set), pg. 22