Twilight Sparkle was born deep in the New Lunar Republic. When her cutie mark appeared her parents secreted her away to Canterlot, hoping to keep her out of Nightmare Moons army. Celestia, taking pity on the ponies, took Twilight in and placed her in the School for Gifted Unicorns.
 
Years later, Twilight became curious about her origins. Her curiosity led her undercover into the New Lunar Republic, where her cover was blown by none other than her own brother. Imprisoned, Twilight was tortured, but she never broke. It wasn’t until Nightmare Moon herself questioned her with dark magic that her mind was shattered, and her loyalty broken.
 
Nightmare Moon decided that the best way to test her new plaything was to send her to Canterlot. Using her intimate knowledge of the castle, Twilight was able to decimate the defences, and Nightmare Moons army burnt the city to the ground.