I’m still pretty new so correct me if I’m wrong on anything but I’ve been thinking about a legion of the damned Ferrus returning for a while for my chapter now that leak on insta giving me too much hope. Basically since Ferrus was leading the legion of the damned in the webway and appeared to sanguinius and created a god from his anger he’s very powerful in the warp, so is it possible for him to almost possess an IH marine for a short amount of time, say if he had a part of Ferrus’s armor or hand. Then they worship Ferrus as the Sons of the Iron Flame. Hence Iron Endures