As for why she had lost the game system, she had probably figured it out: it was not that YGGDRASIL's game system had abandoned her for some reason. Rather, she had abandoned YGGDRASIL's game system.
Tamamo-no-Mae had used the cheating method of Return to the Past to kill Aya from the past—the Aya who had only just arrived in this world and had made no preparations whatsoever.
The change to the "past" had reset the "future," and at the moment Aya was killed, [that presence] within her awakened.
Actually, "went berserk" was probably more accurate than "awakened." If she had been allowed to run wild, this world would likely have been destroyed outright.
Could Nazarick have stopped her? The chances were slim...
Ainz and Nazarick certainly possessed the brute force needed to destroy the world. Given enough time, they could kill every living animal in the world and burn every inch of organic matter to ash.
[That presence] did not destroy the world through "violence." She overturned and remade the entire world from its very foundations.
For example, if the world were a civilization drawn on a sheet of paper, then ordinary world destruction would mean erasing the civilization depicted on the paper, or blotting it out with black ink.
But [that presence] destroyed the world by treating the entire sheet of paper as raw material and feeding it into a papermaking machine to be remade.
In terms of scale, it was simply not "violence" on the same level.
Fortunately, Aya—or rather, Kaguya's will—suppressed her crazed mother. She had nearly failed at that step, but in the end, she succeeded.
Then, the already dead Aya used the spacetime coordinates of Primordial Fetal Movement, which Aisha had sent into the past, to complete Independent Manifestation.
During this process, her fusion with