The Library Sanctus is the name of a vast Imperial archive of ancient knowledge located on Terra. Within its vaults, it holds information on some of the most ancient and sinister events and artefacts of the galaxy, including the history of the sentient robots called the Men of Iron and the Necron device known as the Ymga Monolith.
Sources[]
- Warhammer 40,000: Rulebook (3rd Edition), pg. 278