Long before the knowledge of Celestia, an evil came to be. In the darkness, its power grew and so did its hunger. Thousands of years later, it awakens and threatens to devour and destroy all life.

When Celestia, Luna and Discord are defeated by the monster, Twilight Sparkle and her friends confront it, only to find that they are severely outmatched. Just as she begins to lose all hope, Twilight remembers a spell that could be powerful enough to defeat the monster, but only at a terrible price.