Here's what I know:
Long ago, there were no Necromancers, and no one even thought about them, and everything was fine. But then, this movement began to form, and the mages cursed them, so they left the silver cities and created their own state with undead and ghosts. As far as I remember, this was before the orc uprising.
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I thought of her as a kind of priestess, knowing the will of Ashi.
Namtaru was a symbol and a being connected to the consciousness of Ashi, so she periodically prophesied.