‘Come on, Lily.’ Out there was some unfathomably deep hole, drilled down by Nightmare Moon's body when Princess Celestia blasted her off the face of Equestria a thousand years ago. And at the bottom of that Tartarean pit was where that powerful villain had rested, the merging of Princess Luna and her own malevolent 'Accursed Shadow' from another, demonic dimension, which the Princess had summoned and bound to herself as a pathway to power. 