Her name — Moonlight Eclipse
Can control the moon and stars, but cannot enter in dreams. Envious and jealous. She wanted to become a real princess, but the throne of the changelings was taken by her cousin — Capella Lucanus (the daughter of Celestia and Thorax), and the throne of Equestria belonged to Twilight Sparkle. Because of this, she teamed up with Mohs Fortun (the son of Sombra and Radiant Hope ), to take over the weakest kingdom — the Crystal Empire