Tiber Acron was one of the Raven Guard’s field commanders during the later years of the Great Crusade, operating under Primarch Corvus Corax. He served as one of the Legion’s Shadowmasters — a title used for captains and senior officers whose speciality lay in infiltration warfare and deep-strike operations.

He’s best remembered for leading several reconnaissance and extraction campaigns where the Raven Guard acted as the eyes and knives of the Imperium, gathering intelligence before planetary compliance assaults.