Dark Mechanicum

From Lexicanum

The Dark Mechanicum was a sect of Techpriests of the Adeptus Mechanicus who pledged loyalty to Warmaster Horus at the end of the Great Crusade.

Horus gained the loyalty of the group after promising them STC technology gained from the worlds of the Auretian Technocracy. They supported him during the start of the Horus Heresy and were present on Istvaan V where they used dark and forbidden knowledge against the Imperial Loyalist forces. ¹

Source

• ¹:Fulgrim by Graham McNeill