Her best and only magic teacher, Sunburst, abandoned her. Proper Step refused to teach her magic; it wasn't "lady-like." She runs away and learns to fight with hoof and magic, to save her lifeābut doesn't realize she's becoming somepony's sharp tool.
Luna spent a lifetime on the moon above Equestria... Not just by the Elements of Harmony, no, but by Nightmare Moon herself. Trapped inside of her own mind, she was left to wonder and to lament... how many seconds are in eternity?
Sunset Shimmer has her eyes on Starlight, one of the most popular girls at her new school, but what starts as a plan to save Starlight from her worst enemy/best friend takes on a life of its own, and soon their high school is feeling a lot emptier.
Nightmare Moon, a force of dark evil that tried to blind the world to the light has gone, has since been sealed away and unable to return. However...she may not be the only power that resides inside the Princess of the Night.
(Featured on EqD) Starlight Glimmer was always destined for greatness. But when fate isn't all it's cracked up to be, it'll take the help of some friends to change the course she set for herself. But that's not the hard part - it's letting them try.