Prologue
Year 986 of the 4th Age
Sunset Shimmer stalked the seldom-used corridors of Cant’r Laht Castle, agonizing over the potential of her future. She wouldn’t be allowed to stay in the castle much longer, now that she was certain her days as Celestia’s apprentice were numbered. The ancient sorceress had ceased her engagement with Sunset some time ago, but the stroke that had convinced her things would soon be at an end was the recent accession of Celestia’s other apprentice to alicornhood. It should have been she who achieved that hallowed transformation, not the weak-willed Cadence. Yet, in this matter, Celestia had made her favor clear.
Unlike Lady mi Amore Cadenza, who’d been publicly paraded around as Celestia’s protégé and successor, Sunset Shimmer’s apprenticeship had been kept secret. It wouldn’t have surprised the young sorceress to learn that Celestia had had many secret apprentices over the years, though none had ever come forward; why was that? Given what she knew of her mentor, they had likely failed and been discarded by the ancient enchantress. Sunset Shimmer had no intention of being executed secretly by Celestia, but where could one run from the most powerful living sorceress? Perhaps she could flee to Zebrikaania, or Tyrannus—but would the Padishah or a dragonlord accept her and refuse to turn her over to Celestia? She could flee to Stygra and attempt to vanish, but would she truly be safe even so far away?
Sunset heard a door open ahead; sending out magical feelers, she discovered that it was one of Celestia’s guards. Were they on patrol, or searching for her? She wasn’t ready to start killing guards yet, and certainly not within the castle, where Celestia was likely to sense their deaths and swiftly exact judgment. Casting a spell to silence its hinges, Sunset Shimmer opened the door next to her and slipped into the storage room beyond.
The guard trotted past outside, none the wiser about the hiding sorceress, but Sunset still hesitated to leave her hiding place. There was something in this room emitting a powerful magical pulse that she hadn’t been able to sense from outside. Had Celestia hidden away a powerful relic here and forgotten about it in her many centuries of life? Could that relic be the key to Sunset’s escape? Carefully, she shifted the chests and rolled-up rugs that took up most of the storage room’s space until she was face-to-face with a tall, cloth-covered panel. Sunset drew off the cloth, and it pooled on the floor to reveal a full-body mirror. The mirror was elaborate, its edge ornately gilded and decorated with jewels.
The mirror’s face was more perfectly reflective than any mirror Sunset Shimmer had ever seen, and it was easy to believe another pony was reaching out to her as she lifted a hoof to its surface. Her hoof encountered only minor resistance as it touched the mirror, and ripples passed over it as it began to pass through. The sorceress gasped and yanked her hoof back, returning the mirror to normal. Tentatively, she pushed it through again, her head and torso quickly following the hoof until her body had passed through completely. In mere moments, the young sorceress vanished from the universe of Equus and journeyed into a strange new world.