Triad Ferrum Morgulus
The Triad Ferrum Morgulus were the original three Titan Legions of the Collegia Titanica. Founded during the Age of Strife, they aided the fledging Cult Mechanicus in conquering their enemies, such as the Cy-Carnivora and Mutants during the civil infighting on the Red Planet.
- 1: The Horus Heresy Book One - Betrayal, pg. 138–140
- 1: The Horus Heresy Book Five - Tempest, pg. 145