A long time ago, an evil witch named Hydia sought to destroy pony-kind. Now her granddaughters, Grackle and Dyre, are back to finish the job! With the School of Friendship overloaded with students, Starlight Glimmer and the Mane Six reach out for help. Enter: Violet Shiver, Shadow Storm, and Black Belle! But these ponies aren’t quite what they seem; in fact, they’re working for Grackle and Dyre! With their sights set on revenge and a brand-new Smooze on hand, the young witches and their dastardly creations are ready to cause some mayhem… Can their plan work? Will friendship begin to fall apart as Grackle and Dyre wreak havoc in Ponyville?