Black Crusade (RPG)
This is for the RPG, not the apocalypse-style crusades by Chaos.
Black Crusade is the fourth Fantasy Flight Games Warhammer 40,000 Role-Playing Game, and it's main focus is the forces of Chaos, like cultists and the Traitor Legions.
One of its greatest features is encouraging competition between players, often by making the personal goals of their characters mutually exclusive, thus mirroring the climate of a chaos warband. This can go very right, or oh so wrong.
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