I'm making an evil AU where the main six are switched with the villains.

Twilight Sparkle was a shadow creature who was reborn a unicorn. She always knew of who she was, and decided to gain the trust of the ponies from the crystal empire who found her. As she grew older, her powers began to increase. Then she found out about the powerful magic that turned Princess Luna into Nightmare Moon. She was able to contact the dark moon spirits that changed Luna, and they managed to fuse their body with Twilight's. Thanks to her new powers, she became a powerful alicorn. She overthrew the old rulers and became the new queen of the crystal empire. She currently rules the Crystal Empire with an iron hoof.