Spoiler!
The MC is one of the three Original True Ancestors, originally they were described as the incarnations of the Heavenly Dao, but the Author later retcons this. Now the origins and birth of the Original True Ancestors is a mystery, all we know is they existed before Chaos, before the Heavenly Dao. They just appeared out of nowhere and destroyed the Old Cosmos and turned the Heavenly Dao into a puppet. However, despite who unimaginably powerful they are, they sensed another Realm, another Level, and they all wish to Transcend and reach this level. Each Original True Ancestor has their own Philosophy on how to achieve this, Xuan (Profound) only acknowledges in themself, believing that their lack of strength lies within. Xuan remains determined to search within themselves for another path, striving to derive a method that can truly empower them. Shen (Divine) believes that the existing world was incapable of containing power greater than theirs, that the Realm of Reality itself was incomplete. Thus, from the essence of their origins, they discerned and brought forth the concepts of indestructible matter and creation matter. They formed the Vast Expanse, essentially a garden to harvest these Matters, and the Source Realm is formed from it. They formulated a comprehensive system of calamity cycles, to ensure the balance and order of all beings. As a result, periodic minor calamities occurred every few eras, major calamities occurred every few hundred eras, and epochal calamities that plunged all of existence in the Vast Expanse into an epochal winter, marking the end of an epoch. But the MC, Zhen (True) has meticulously planned for countless eons, devising a scheme to devour and eliminate the other two True Ancestors, completely erasing them from existence. MC basically created a Secondary Account to further the Main Account/True Body. So mc created what we know as the first identity, the Lord of Heaven/Source of Darkness who created the Daitian Organization and dominated the Vast Expanse, but at some point the MC wanted to destroy that identity and the Daitian Organization, but he was way too powerful, the Vast Expanse couldn't possibly defeat them, when mc was thinking of a way to make the act believable the First Artifacts or Civilization appeared, and the vast expense ralied, besieged the mc and sealed the Lord of Heaven, but in reality the mc wasn't ever really sealed, just a part of his power. At some point a part of the mc's power "escaped", and took the identity as the Lord of All Demons, and "coincidently" came across the Mountain and Oceans True World, a new born Nascent True World, that was undergoing its first Great Purge, mc intervened, saving the True Spirit Qingyi and saved the world, this was the beginning of the innocent Qingyi's fall into depravity. Later during the Forbidden Epoch, the 2nd great purge was already upon the world, but the world still hadn't recovered and had no chance of surviving, so MC and Qingyi devised a plan to Destroy the world, to give a reason and deceive the Source Realm, they put on an act, the MC would accept a disciple, and having spent every waking moment together would develop feelings for her, Qingyi would get Jealous. Later MC and Qingyi fall out and MC destroys the world, to make the act more believable the MC's True Body personally sent down a Lightning Tribulation to destroy the Demon Lord. In reality, Qingyi was always a pawn, she was the 9th Princess of the Jin clan, the Epoch Cicadas whose home is the Mother Tree of Epoch, MC's True Body snapped the Mother Tree of Epoch because it was absorbing too much Fortuity, and too soothe the wrath of the Source Realm the Ancient Burial Civilization (who serve as something like the outpost for the Source Realm) contacted the Source Realm and asked for a way, and they were told they could offer a Sacrifice, and Qingyi was chosen as said sacrifice which she believed was decided by her sisters and mother, she would later escape the Ancient Burial Civilization with the Immortal Flame Core, and later utilizing the unique talents of the Epoch Cicadas would become the Mountain and Oceans True Worlds True Spirit.