After sensing a magical disturbance in her old castle, Celestia decides to investigate, what she finds is a odd black cat and strange baby dragon, seeing that the drake has no place to live, she decides to take them with her, all the while trying to survive several attacks from a large number of unnatural animals with the ability to use magic, all of them coming from a time before Celestia's birth. Meanwhile in Ponyville strange things are happening all throughout the village.
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(Im not exactly the best when it comes to descriptions)
Takes place after season 4