Trixie Lulamoon

Trixie is a unicorn pony and a traveling magician who is featured as the main antagonist of Boast Busters and Magic Duel and makes background appearances in Bridle Gossip and The Return of Harmony Part 1. She tends to speak in the third person and refers to herself as "The Great and Powerful Trixie." Trixie visits Ponyville with her one-mare show, in which she shows off, extremely exaggerates, and boasts about her abilities. The name Trixie is a diminutive form of Beatrix.

Rivalry with Thomas
When Thomas first met Trixie, he thought she was just a show-off. Diesel showed everyone just how powerful Trixie was, but Thomas didn't believe him. Though he was her best friend and loyal helper, Diesel plotted against Trixie and finally revealed his secret to his friend and betrayed her, snatching the Alicorn Amulet as he did so, as well as snatching the green amulet that Trixie was wearing as she was declaring herself to be more greater and powerfuler. Declaring himself to have been under Trixie's command for too long, Diesel obsorbed the Amulet's power to turn himself into a powerful scourcer. But Thomas fought Diesel as a robot and freed Trixie from his control. Though he was defeated very easily, Diesel still had some of the Amulet's power left in him and declared himself to be more greater and powerfuler than Trixie, before fleeing from Equesodor. While Trixie's clone and Sunset's clone join Starscream.
 * Thomas' Adventures in Transformers: Prime

Trivia

 * Trixie will become Winnie the Pooh's enemy, but later turns good, in Pooh's Adventures of My Little Pony Friendship is Magic.
 * Trixie will become Thomas' enemy, but later turns good in Thomas' Adventures of My Little Pony Friendship is Magic - Magic Duel and will make her guest starring appearnce in Thomas and Twilight Sparkle Spends the Night at the Museum, Thomas, Twilight Sparkle and the Adventures of Rocky and Bullwinkle, Twilight Sparkle's Adventures of Sleeping Beauty, Thomas and Twilight Sparkle Spends the Night at the Museum 2: Battle of the Smithsonian, Thomas and Twilight Sparkle in Fantasmic (Walt Disney World Version), Thomas and Twilight Sparkle's Adventures of The Prince and the Pauper and Thomas and Twilight Sparkle's Adventures Chronicles helping any friend in need.
 * Trixie will be Jimmy Neutron's enemy, but turns good in Jimmy Neutron's Adventures of Pokemon: Jirachi Wish Maker.
 * Trixie is also Prince Blueblood's Wife.
 * Trixie will become an Alicorn in Yuna's Destiny Part 2.
 * Trixie along with Twilight Sparkle and Sunset Shimmer are Princess Yuna's Mentors.
 * In Stuingtion's film: Thomas and Twilight Sparkle find Atlantis The Lost Empire, Trixie will be trying to kill Twilight but ends up being terminated by our heroes, and isn't seen in any of Stuingtion's future films.
 * Trixie is best friends with D199 and Diesel. But her clone is Diesel's boyfriend.
 * In Toonwriter's videos and universe, Trixie is absolutely NOT a Decepticon, or a train, and she's especially NOT deceased.