As the eternal regent of Equestria, Princess Celestia's knowledge of magic is without equal. Over her long life, only a few gifted ponies who had a great destiny before them have had the honor of learning at her side. Sunset Shimmer was one such pony: one of Celestia’s best and most promising students. As she learned at Celestia’s hooves, their bond strengthened until they became far more than student and teacher to one another.

Sometimes those closest to us are the ones who can hurt us the most.

[Note: This story does not directly tie into Equestria Girls]

On a dark night filled with even darker magics, an insane cult attempts to give Nightmare Moon a body and life of her own, utterly separate from Princess Luna. But, when the spell is interrupted by Celestia, something unexpected is created.

Now, a little black alicorn filly named Nyx finds herself living under the care of Twilight Sparkle, only to be haunted by memories and emotions from her past. Is she Nightmare Moon reborn or is she simply a doppelganger with a soul and mind of her own? Can Twilight Sparkle protect Nyx from those who refuse to see past her dragon eyes and black coat?

Or, will Nyx be forced to inherit the sins that may not even be hers and become the greatest evil Equestria has ever known?