Princess Nightmare Moon had tried to keep it secret. She had feigned ignorance, but the charade could not last. She nocked the arrow. Tirek was a large target; he would fall easily. Then the true challenge would come: explaining herself to Celestia.
Nightmare Moon won. She defeated Celestia, broke the Elements, banished the sun. This all happened a very long time ago. So long ago, that she has had plenty of time to change her mind. Not that fixing it will be simple.
Propaganda is a powerful thing. She took my crimes, my failures, and turned them into a wives tail. Into something you tell your foals to get them to come inside at night. Be good or Nightmare moon will come and eat you up.
Luna, with the reluctant help of Nightmare Moon, sets out to remedy her past mistakes and return the sun to Equestria. Meanwhile, Queen Chrysalis tries desperately to save her species.