|Allegiance||Unknown; Formally Imperium of Man|
The Graven Spectres are a Space Marine Chapter of an unknown founding. They eventually went, renegade and their only significant appearance had them being overshadowed by the Grey Knights in their 7th Edition Codex.
In year 365.M41 the Graven Spectres decided to attack the planet of Syban, a relic planet with a large amount of stasis technology. While raiding one of the world's great vault, the Graven Spectres broke open a tomb containing a demon prince. Said Demon Prince proceeded to use the technology around him to bring more demons in. In a twist of fate worse than death, a squad of Grey Knights were the closest to the planet. The Grey Knights arrive and fight their way through the demons and corpses of the Spectres. As a last-ditch effort to stop the demons, the Grey Knights activate the planet's failsafe stasis technology and freeze the planet in time.