She-Who-Steals-The-Flame

Also known as Shra-Tak Cor'Mezra in Abyssal, She is an evil spirit dedicated to stealing the power of the heavens. The is involved in an ancient Nordic legend concerning a star that fell to earth and a hero that had to defeat her in order to preserve the balance and keep the power from falling into the wrong hands. At the end of the legend, the hero of the story ascends to the heavens and becomes the star known as "Sentinel", taking its old place in the heaven.
Whether or not this legend is true, the demon with the name that the legend's antagonist bears is very much real, and was imprisoned a few decades ago by powers unknown. Recently however, she was set loose upon the world again.