Sunset Shimmer is sent to Ponyville to prepare for the Evening Moon Celebration. But this is an unusual summer, for a certain mare of flames escapes the sun to plunge Equestria into eternal heat...

Generations after the banishment of Daybreaker, Luna has begun a school for gifted unicorns, hoping that a future hero of Equestria would release Celestia from Daybreaker's grip.

What if instead of Luna being corrupted, Celestia was corrupted instead? And how will Celestia's corruption be different?