The Traitor Legions were responsible for most of the atrocities of the Horus Heresy, but alongside them marched untold millions of human cultists whose devotion to so-called ‘Warp cults’ bred countless horrors in every corner of the Imperium. In today’s excerpt from the Black Books, our ongoing series looks at the human toll of the Traitors’ meddling with the Warp.

Warp Cults had been encountered numerous times throughout the Great Crusade, though usually in isolated incidents barely worth recording as part of a larger campaign. Any world that exhibited particularly dangerous Warp activity was simply blown to pieces from orbit and forgotten, on the strict orders of the Emperor.
Alas, when the Heresy erupted into all-out war and the Age of Darkness began in earnest, countless human cultists had already been brought under the sway of diabolical demagogues – in large part, from the Word Bearers Legion. It was at Calth where the first mass deployment of cultist forces wreaked havoc on the Imperium, but soon after they became a fixture of Traitor battle plans, where they provided a useful and disposable mass of mostly compliant bodies to use for garrison, menial labour, and other unsavoury duties.
Today’s section is taken from The Horus Heresy Book V: Tempest, first released in 2015, which dealt primarily with the devastation of Calth and the resulting bloody feud between the Ultramarines and Word Bearers.
Keep your own warp cultists in line with a Traitor Overseer Consul, and then join us again next week as we delve further into the profane worship of the Immaterium, with an overview of the daemonic Hidden War.












