Twilight Sparkle, Applejack, Rainbow Dash, Rarity, Pinkie Pie, and Fluttershy are sent by Princesses Celestia and Luna to a foreign land outside of Equestria known as Mytholand, inhabited by strange ponies, to defeat the new villains: the Four Apocalyptic Sisters.

(Based off of The Four Horsemen of Apocalypse from the Bible, as well as Norse mythology Sleipnir; Scottish mythology Will-o'-the-Wisp; Greek mythology corruption of the cyclops: the triclops; and Greek mythology Typhon. Wisp ponies are borrowed from my little sister and are not my custom pony races.)