Many years have passed since Discord's first defeat at the hooves of the Alicorns. Equestria has enjoyed a time of peace and prosperity under the rule of Celestia and Luna. However, all good things must come to an end.
Equestria is now faced with a new threat from the north. With Celestia unable to fight, the fate of the world rests solely upon her sister, Luna. Perhaps, with the help of a trio of unlikely heroes, Luna can defeat this new foe, and save Equestria in the process.