Being princess for 1000 years means you've received more than a few threats, but somehow Celestia has maintained peace across all of Equestria. It isn't until she is attacked by a mysterious unicorn and her cutie mark is stolen, that all this changes. Celestia is transformed into a husk of her former self. Not alive but not dead either. Twilight soon learns of the Legend of the Harbingers and is forced on a quest to gather the Elements of Harmony to vanquish this new evil. If she fails, all her friends, all of Equestria will be erased from existence.