Scars of Faerûn
Shar, the Mistress of the Night, is the goddess of darkness and the caverns of Faerûn, as well as a neutral evil greater deity. Counterpart to her twin Selûne, with whom she gave shape to Abeir-Toril after Ao created the cosmos, she presides over caverns, darkness, dungeons, forgetfulness, loss, night, secrets and the Underdark.
Among her array of twisted powers is the ability to see everything that lay or happens in the dark. Shar’s symbol is a black disk and her followers always infiltrate the highest ranks of governments and try to control the course of nations and cities.
In Netheril, when someone is a follower of Shar, his or her word is often considered law.