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Nightsong(Sword of Thorm? Product of Forge?) Lost in Underdark
the Nightsong seems to be an avatar of Shar. [Linked Image from i.imgur.com]
according to her voice lines, she was bonded in the ancient temple by Ketheric Throm. Her ability allows her to transform Sharrans into shadows. Also, another voice line suggests that she was made into this form, and it could be what Shar want SH to become
also, Ketheric Throm
A voice line from the narrator makes it very clear that he's one of the chosen of the Absolute now, which matches with the description of "an armoured male elf, exuding power and command".