The last page of the book mentions that a Crystal Heart is the centerpiece of the Faire. Twilight uses her magic to cut one out of a crystal block but later discovers that the Heart is an actual relic that King Sombra sealed away long ago. According to Amethyst Maresbury, the whole purpose of the Crystal Faire is to lift the spirits of the Crystal Ponies, so the light within them can power the Crystal Heart, so that the empire can be protected. Twilight announces the beginning of the Faire from the castle balcony.