Trixie first appears in Boast Busters, where she assumes a very theatrical personality and speaks dramatically in the third person, posing and setting off fireworks to complete the full effect. Twilight Sparkle's positive, helpful, and humble attitude is contrasted by Trixie's over-the-top boasting and arrogant nature. Trixie claims to have saved Hoofington from an attack by an ursa major. However, when confronted by an ursa minor, she admits that her tale was fabricated and that even the ursa minor was an opponent far too powerful for her to contain. This is the only point in the episode where she drops her "Great and Powerful Trixie" persona and speaks in the first person. Despite this brief display of honesty and fear, her frequent showboating alienates the other ponies and classifies her as an antagonist of the series.
In Magic Duel, Trixie returns with her magic augmented by the Alicorn Amulet and she uses this power to take revenge on Twilight by cheating in a magic duel, banishing her from Ponyville and subsequently setting herself up as the leader of the town. She shows no qualms about using innocent ponies (Rarity, Rainbow Dash, Spike, Snips and Snails) to prove her power, nor does she seem to care when a spell nearly takes out another (Shoeshine). Through the episode, she has Mayor Mare trapped in a cage, forces other ponies to do manual labor for her, and claims to not "trust wheels." She was also easily manipulated by Twilight Sparkle into a rematch duel so she could prove that she was still better, which eventually lead to her downfall. However, upon removal of the amulet and the loss of her power, she accepts her defeat against Twilight, unlike her first visit to Ponyville, and meekly seeks forgiveness for how she treated her and her friends. At the end of the episode, she once again drops her persona and speaks in the first person, but only for a few seconds before she refers to herself as the "Great and Apologetic Trixie."