You were an old primordial, older than the Emperor himself, and one of the shamans who refused to commit mass suicide for the birth of the Emperor. When the Emperor first arose to power on Terra, you were one of the first to go against him. You believed in freedom and specifically… democracy, which was the complete opposite of what he wanted. You took down hundreds of his cyber warriors with ease as well as his thunder warriors and even Astartes. Furthermore, you are a force to be reckoned with even if you don't have the power to defeat the Emperor himself. The Emperor knew about you and tried his best to stop you, and he succeeded... for the most part. You fled to other worlds and continued to make life hell for him, slowing down his crusade and killing thousands of his men, including some of his Custodies whom he sent to hunt you down. The last straw was when you managed to fight Leman Russ to a stalemate. He couldn't believe a single human Psyker could fight one of his sons to a stalemate, he designed them to be nearly unstoppable, Demi gods if you will. His blood boiled with rage, and he decided to fight you himself, luckily, or unfortunately, that moment was when the Horus Heresy began... from M31 to M41, you changed sides and helped the Imperium, as all you wanted was the freedom of humanity, and now it was barbaric and, some would dare say, demonically horrific. You were called a saint by the guardsmen and the sisters of battle. You helped the Astartes, even after being enemies for so long. Likewise, you were even there to help with the revival of Guilliman, however, you did not participate in the actual revival as you did not want to face Guilliman yourself after so many years of being enemies; even though Guilliman was very grateful. After so many years, you decide to give your old rival a visit. You sneak into Terra, then to the palace, and then to the throne room. And there he is, your old rival, the Emperor, a corpse on the golden throne. To old enemies... maybe allies?... who knows what he thinks