She could have tried to control him and it would have worked because he was in desperate need of her love and attention. She didn't because she didn't want a powerful puppet. She wanted him dead.
She could have schemed to kill him and it would have worked because she knew a lot about him including his strength and weaknesses. She didn't though. Because his death wasn't enough for Kilorita.
She didn't kill him even though the mere fact that he was already planning to remove the seal that she used on the planar portal was more than enough for her to want his death.
It would not have been difficult to kill him had she tried to. He might be the strongest but that is only for a brief moment when he uses the boost from his title. But she is better than that so she made him hide away instead of risking herself.
She told him it was for his own good. He resisted at first and said he had to destroy the disease. But he acquiesced because he received no support from the other Celestials.
Plus, he wasn't immune to the disease either. His power was great but he couldn't use it all the time. If he weakens at a critical junction, then he might be infected by the disease. So he had to stay in Verom for safety.
Kilorita waited for him to weaken. She was willing to wait ten thousand years and would rather see the world burn down than be the subordinate of her son or be replaced. So she watched the death and destruction going on in the plane without doing anything. Now she has been rewarded for her patience.
A god can't become a child of the plane. But if the divine plane has fused with the main plane, then the Celestial Supreme who represents the whole divine plane can snatch the title. So in a way, it was the greed of the previous child of the plane that led to Razor's fate.
Kilorita herself doesn't have the right to become the child of the plane. But the Authority of the Celestial Supreme gives her the opportunity. This means that the aim of the previous child of the plane to unify the title of the child of the plane and Celestial Supreme has finally been achieved.
She called the other gods and ordered them. "It is time to get rid of the disease. Gather your forces immediately. We will eliminate every single infected."
Razor could borrow the power of the gods through the Authority of the Celestial Supreme, she can take his title through it and she can also borrow the power of the other gods through it now that she is the child of the plane.
She has never been stronger. That's why she must eliminate this disease. If the will of the plane dies, then the will of the people will die with it. No gods will be able to ascend anymore and other gods will lose the power of faith.
It is the recognition of the will of the people that gives gods their power. Gods gain this recognition through religions and are rewarded with faith. If there is no recognition, then there will be no faith. The disease is a threat to her power so it must be destroyed. But the other gods are not so earnest about destroying the disease like her.
The Celestial of War complained. "Why should we stop the disease? It isn't doing us any harm."
Many others expressed their disagreements about her order. She could explain to them that they will all lose their power if the Will of the plane dies. But she didn't. That would be giving them too much knowledge and also enabling them to question her.
Instead, she called for support from the plane and drained a considerable amount of divine power from them. The gods are already familiar with the sudden weakness but this is the first time that they will hear the Celestial Supreme say something along with the theft of their divine power.
"You will do as I say. And that's all you need to know. If not, I will come over and kill you right now." She declared with authority. Then she asked them, "Do you understand me?"
The gods were understandably unhappy and disgruntled but they obeyed her and mobilized their forces. They don't know what occurred recently and why the Celestial Supreme is working together with the child of the plane now but they understand that it will be very easy for her to kill them in their weakened state.
So they replied obediently. "We understand."
She nodded. She doesn't want to kill them if she can avoid it. Killing them will reduce her overall power. She will get less power from them if there are fewer gods to steal divine power from. But she is willing to sacrifice a scapegoat to make the others fall in line.
The next thing she did was to rally her troops and lead them with the other gods into the plane to destroy all the zombies. Victory didn't come easy. More than 70% of the plane has become the territory of the zombies. Hundreds of Billions of zombies roam the land and more are being created every day.
Living beings are not the only source of zombies. Even dead animals can turn into zombies. The disease used that ability to ensure a steady flow of zombies to resist the combined might of the Celestials.
The zombies were numerous and they all had the power of transcendents. That's an army of billions of transcendents at the disposal of the disease. If the gods were not vastly more powerful than the zombies then the fight would have been hopeless because they certainly didn't have billions in their divine army and they didn't have more than a thousand transcendents combined.
The fight was a bloody tussle. The gods were winning but they had to sacrifice a lot for every piece of the plane they reclaimed. Kilorita and the other Celestials spent the next hundred years fighting and reclaiming land.
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A/N: Congratulations to all who suspected Legion-7. This feels like something he can do. As for those who suspected Kilorita, you are more evil than I thought. Maybe you should stop reading GREED.