Celestia has reached the eldest age for an alicorn, and in order to continue lifting the sun for Equestria, she has no choice but to transform herself back into a filly.

She's left herself, and Luna some very detailed notes on what to do next.

*Breaks away from canon events happening in Season Nine. For example, Cozy Glow is still trapped within Tartarus.*

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?