The war is described as a major contributing factor to the game's dystopian environment. Penned by several authors, the series takes place during the Horus Heresy, a fictional galaxy-spanning civil war occurring 10,000 years before the far future of Warhammer 40,000.
The Horus Heresy is an ongoing series of science fantasy set in the fictional Warhammer 40,000 setting of tabletop miniatures wargame company Games Workshop.
