The demons are wrong, of course. The Tree Father is not just stealing the first abyssal plane. He is refining it into his core, and he will do more. They can be forgiven for that mistake because there's little difference between what he is doing and what they claim he is doing for now.
But they are wrong about his plans for the abyss. He doesn't plan to refine just the first abyssal plane. He plans to refine the whole abyss. That way, his world forge will be very strong. So not only is he stealing the first abyssal plane, he plans to steal every plane in the abyss too.
As a divine spark, his future is to become a world forge. He needs three things to achieve that. He needs a lot of cosmic energy, a world engine, and a world forge. When he has all three, his divine spark will light the spark in the forge, kickstart the world engine to power the world forge, fuse the two of them together with cosmic energy, and then he will become a maker of worlds.
A world forge is a phantasmic structure created with refined layers of space, energy, and matter. The best thing to use to create a world forge will be a lot of world fragments. Each world fragment he uses will make each layer of his world forge very powerful because of the world engine the world fragments possess.
The next best thing are divine planes. Divine planes don't have world engines, but they have the Authority of the Celestial Supreme. That is practically a substitute for world engines, so it will do as the second best. The third best are abyssal planes. Even ordinary planes are better
than abyssal planes since they have life crystals.
Unfortunately, World fragments are expensive and not available for him to use. There are only two divine planes that are available to him, but he can't have one while Aeternus has destroyed the other. He also can't have any plans since they have either been infected by demon gods or can't be stolen for fear of Mother High Heaven.
This leaves the abyss for him to use. So he didn't target the abyss because he was being choosy. He targeted it because he had no choice. This is the best he could lay his hands on.
The first abyssal plane was soon lifted up into the sky. It was done slowly and carefully, so it was still intact. The white barrier around his core expanded rapidly. It pushed the ring of white fire away, so the ring also expanded. The white barrier expanded until it covered the first abyssal plane. Then it fused with it and began shrinking.
The first abyssal plane resisted the shrinking, so the ring of fire got to work on it. The ring of fire turned into a sphere that surrounded the white barrier and the first abyssal plane. The whole plane was then refined spiritually into a layer of the world forge.
Everything on the plane, including the people on it, was burned to death. Their souls were converted to divinity, which was used to enchant the refining process.
The resistance of the plane reduced, so it shrank slowly back to the multicolored orb at the center. It was refined into a ring of metal etched with runes of power. It became the first part of an artifact that will be used to forge worlds in the future.
This is all good for Legion, but more good things came along. The demons don't like intruders in the first place. They don't like intruders that are stealing from them even more.
Many demon kings didn't care about the theft, despite their hatred for intruders. They knew it was just a matter of time before the abyss was destroyed, and there's nothing to gain by stopping someone who's doing just that.
The Tree Father is only doing something the era of conquest will do to the abyss. So the demon kings were more interested in going to the Tyrant realm to wreck destruction and carnage before they ran out of time to do that. That will bring them tangible benefits. If they hadn't heard about the perpetrator being a god, none of them would have taken a step to interfere in the theft.
Apparently, some of the demon kings who had been on the first abyssal plane when the Tree Father came had spread word about the presence of a god. Not many believed it until they saw the culprit of the theft.
They heard it was a god that LIES and GREED had been hiding, so they came running. Even the ones who were cautious enough to ask the question, "Where are LIES and GREED?" couldn't overcome their resistance to something that could make them world enders. So they came in droves to their deaths.
None of them could get close to the god at all. Something was always cutting them off. The demon kings and demon gods didn't know that the god's act of stealing the abyss was bait for them.
Aeternus wanted to eat all the demon gods, but he couldn't go hunting after them because he didn't know where they were. Even Soverick's prediction couldn't find them reliably because of their Supreme Law, their chaotic nature, and the vast amount of energy that they carry. It was better to do something to attract them.
Their plan worked. Many demon gods came around to check out this god. They came to feed themselves to the waiting jaws of Chaos. This streak of unfortunate deaths didn't discourage the demon gods at first. The flesh of a god was that enticing.
Plus, there were certain demon gods that kept fanning the flames in the background. They instructed some demon kings to release certain enticing information about the god so that many other demon gods would encounter the calamity that they experienced.
Aeternus ate and ate. He ate as many demon gods came looking for trouble. The only demon god that didn't suffer was GREED from the high heaven realm. He took a look at Aeternus and ran away.