 "Black Crusade", essentially, is the corrupted version of previously mentioned Warhammer 40,000 roleplaying games.Characters are cast in the role of the villain, with the players actively working against the Imperium and for the forces of Chaos in the sector.In "Only War", each player takes the role of an Imperial Guardsman, one of the billions of hardened conscripts constantly fighting on myriad fronts at the whim of the Earth-based government of the Imperium (Adeptus Terra).