In the Crystal War timeline, Starlight - not Twilight - became Celestia's student after Sunset. She became the leader of an alternate Mane Six comprised of herself, Trixie, Night Glider, Lightning Dust, Suri Polomare and Double Diamond. However, Starlight proved to be just as power-hungry as her predecessor: she betrayed her friends and defected to the Crystal Empire, becoming Sombra's right-hand mare. The name "Starlight Glimmer" is now synonymous with treachery in Equestria.