The Undying was there to witness the day the world broke.
The day he was free of the eternal darkness was the day that would lead to the world being in an eternal war.
Humans attacked other humans because they were different and started calling them demons.
The Undying went on to fight in the war. He fought Immortals, Divinities, and Celestials. No matter how much damage he took, no matter how many times the people killed him, he still came back.
Slowly, the demons praised the Undying to be something bigger than they all were.
They called him the Undying God.
As the war progressed over thousands upon thousands of years, the Undying God became one of the prominent figures in the war.
However, he saw that he was going to die in the battle ahead, so he left behind an inheritance that someone worthy would soon acquire.
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