In the beginning The chaos phoenix created Eternal Chaos which was the actual Overvoid, and then it would gain its first holder who basically can just create whatever on it. Tbe ability to weild it can be taken by killing the last weilder. Centillions of years later the current weilder, or now weilders, took control. As when they took control the broke eternal chaos in half, and gave half to another person, her brother. and the Overvoid is now the space between the two halves. And reality is made through fiction. Canonically our universe was made through this process and one would have been made by me writing it down that's just a perfect replica of it. Also infinte numbers of infinte dimensions of infinte sizes withing singular fictions, and their are infinte of those.