Ancestral energy.
As I said, it has a very simple and at the same time complicated explanation.
First, before the Universe is created, there would be nothing in the Outer realm.
Nothing except Chaos energy that is floating in the air, of course, there are higher energies other than Chaos energy but for now, we will focus on Chaos energy as that is what matters.
After a long time of accumulation in the void of the Outer realm, a place would have a high concentration of Chaos energy. This concentration will keep increasing until it forms a singularity of energy.
When this singularity reaches a certain limit, it would explode with a loud…. KABOOM
At that time we will have a newly born Universe with incomplete laws.
When such a thing happens, a member of a special race of the Outer realm would get attracted to this incomplete Universe by the laws of the Outer realm.