Twilight Sparkle has been betrayed by Celestia, all her friends brutally killed in front of her eyes after the young unicorn woke up one morning with wings. Celestia had realized that Twilight had been chosen by the Elements of Harmony to replace Luna and herself as the leading force of Equestria, and correctly surmised that the other Elements would have followed shortly after and become a united force the current princesses couldn’t hope to defeat if they chose to contest their position for the throne. Even though Twilight doesn't want to acknowledge her destiny as Equestria's next chosen ruler, the new alicorn cannot let the tyrants she has now seen Celestia and Luna really are remain in power.
Armed with only the Elements of Harmony and her burning rage, Twilight sets out to avenge her friends and free Equestria from Celestia and Luna's tyranny.
The fate of Equestria, as well as the balance of this entire universe, hinges on Twilight's success.