 Black Industries chose to set "Dark Heresy" in a previously unknown sector of the game's fantasy universe, the Calixis Sector, within the "Segmentum Obscurus".This sector lies adjacent to Scarus Sector, which is the setting of Dan Abnett's Eisenhorn trilogy.Calixis is similarly adjacent to the Koronus Expanse, the setting of "Rogue Trader", and to the warzone on the edge of the Periphery Sub-Sector, the setting of "Only War".