Celestia, using the mystical "Elements of Harmony", banished her sister to the Moon for one-thousand years, therefore becoming the sole princess of Equestria for nine and a half centuries until Princess Cadence would ascend to become a ruling alicorn princess alongside Celestia.
Celestia banished her sister to the Moon for one-thousand years, therefore becoming the sole princess of Equestria for nine and a half centuries until Princess Cadence would ascend to become a ruling alicorn princess alongside Celestia. Celestia was using the mystical "Elements of Harmony".