Twilight Sparkle: perfect student, lives in Ponyville, has great friends, and the newest princess of Equestria. That was her life before the tragic event happened.
She is transported to a new universe where she never met her friends and lived alone in darkness. Alone in a new universe with some memory problems, Twilight must find out who she is, before losing herself entirely.
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Life in Equestria was perfect for Rainbow Dash. Her mentor, Princess Celestia, has given her a lovely home in a town called Ponyville. She and her friends helped keep harmony in Equestria by restoring Princess Luna to her rightful place as princess of the night.
There have been no problems in town, until a strange alicorn appears and claims to have no memory of anything but her name before appearing.
Rainbow, along with a strange stallion named Blue, wish to help her, but how can she help somepony who doesn't even know who they are themselves?