2,136 years have passed since Twilight Sparkle became an Alicorn. Peace and prosperity have reigned supreme, and all seems to be going well. With the Bearers of Harmony gone, however, and the Elements themselves missing, an enemy older than Equestria itself has been allowed to return. With darkness descending on Equestria, and a powerless princess on the throne, it's up to the unlikeliest heroes to return harmony to the land and save the world from endless winter.