Baima, the embodiment of an unstoppable force of destruction that consumes worlds.
The eternal threat, Baima is the personification of the Unknown. Though she cannot truly be proven to exist, those driven mad by corruption claim to have seen a shrouded female form beckoning them further into the abyss.
Perhaps these hallucinations are simply a bias, or perhaps there is a deeper root behind this phenomena.
Later, after Godfall, she is still present in the Valley.