Trixie, a discouraging pony in the eyes of Ponyville. Trixie, a once faithful student in the eyes of Princess Celestia. Yes, Princess Celestia had Trixie as her student before Twilight Sparkle. She was a happy, cheerful filly and wasn't evil whatsoever until Twilight Sparkle, a much younger filly arrived. Before Trixie could harm her, Princess Celestia made her disappear in a flash of green dust.

Now it is the present Trixie, and her jealousy still remains with her, causing her to turn the town of Trothollow completely bland and unenthusiastic. Twilight Sparkle and Trixie must team up to stop the spells that overcome both of them - even the most powerful, non-magical one: envy.