One thousand years ago, history was changed. One thousand years ago, Nightmare Moon was killed. One thousand years ago, Equestria broke, and Celestia had to put it back together.
With her new apprenticeship under Nightmare Moon, Empress of Equestria and Queen of the Eternal Night, the orphan filly Twilight Sparkle plunges head-first into the conspiracies, secrets and intrigues of the Empire.
Thanks to the love bomb at the Royal Wedding, Princess Celestia is revealed to be a Changeling Queen. How will Equestria, deal with this? And why is Celestia a Changeling Queen in the first place?