Iron Warriors are another fascinating and brutal faction in the Warhammer 40K universe, known for their relentless siege warfare tactics, obsession with fortifications, and cold, calculating nature. They were one of the original Legions of the Imperium and were led by Perturabo, a Primarch who was a genius tactician and master of siegecraft. Unlike some of the more charismatic or honor-bound Primarchs, Perturabo was seen as grim, perfectionistic, and somewhat isolated, often dismissed or mistreated by the Emperor and other leaders of the Imperium.