My interpretation of Sunset Shimmer 🔥 no Equestria Girls here, sorry folks…
Sunset Shimmer was born of Queen Celestia’s desire for an heir. The Queen devised a spell that would enable her to create a daughter from her own magic—no mate required. However, the spell was flawed: without the essential component of love, it created an unstable clone rather than a daughter.
Sunset Shimmer was born an Earth pony, but the magic that created her was uncontrollable, resulting in raging tantrums and a fiery mane. She was deemed a failed experiment by Canterlot and although Queen Celestia tried to treat her well, she could only see the worst of herself made manifest. She could not bring herself to love Sunset Shimmer no matter how she tried.
Her daughter grew spiteful and cruel, acting out in desperation for love. Eventually, after badly burning one of Queen Celestia’s students, she fled to the Dragon Lands, never to be seen again… or is she?
Poor Sunset Shimmer. I really love a ‘evil but trying to be good’ clone, a la Fern from Adventure Time.