Life for Trixie has been dificult since her humiliation at Ponyville. However, during her employment in an antique shop, she accidently releases a mad but powerful magician from an old mirror. Taking advantage of his confusion, she decides to use him to help her get revenge on Twilight Sparkle.
I would suggest keeping the story stretched out more. Action happens too fast and it reads like a film script.
But it is still quite a bit better than some of the stories which have better ratings.
I wouldn't give you a favourite yet, since the story has barely started, but here's a thumbs up for encouragement.