In this AU, Princess Celestia is the one corrupted by the Nightmare forces instead, and thus in her paranoia over the growing distance between Luna and herself becomes Phantasm Sky, forcing her younger sister to banish her to the moon when she threatens to usurp the throne. 1000 years later, the Elements of Harmony free Celestia from the Phantasm’s corruption - but can she ever forgive herself for what she has done?
 
Elements of the design are obviously taken from Daybreaker, but since Daybreaker was just a figment of Starlight’s imagination, I decided against outright using her. My goal was to take the idea of a pink nightmared pony (as Celestia’s design is somewhat pink, so I feel a Nightmare Celestia might be as well) and still make it somewhat intimidating. Not sure if I succeeded in that, but I’m happy with the concept overall at least!