- Calendar Man
- A goon and a manager in "New Gotham"
- A goon and a student in "Riddler U"
- Doctor Trap
- A guard in "Catwoman"
- Condiment King
- A singing fish in "Bachelorette"
Outside of the show, he is known for his roles as Hoban "Wash" Washburne in the space western series Firefly and the film Serenity, Tucker McGee in Tucker & Dale vs. Evil, Steve the Pirate in Dodgeball: A True Underdog Story, and K-2SO in Rogue One: A Star Wars Story. Other well-known roles include Sonny the robot in the 2004 science fiction film I, Robot, and the squire Wat in A Knight's Tale.
Tudyk is also known for his appearances in other animated shows and films, most of which being properties of the Walt Disney Company. These roles include King Candy/Turbo in the Pixar film Wreck-it-Ralph, Duke Weselton in the first Frozen film, Duke Weaselton in Zootopia (which is a nod to his previous role in Frozen), Alistair Krei on Big Hero 6 (another film by Pixar) and Ludo Avarius, and River Butterfly, on Star vs. the Forces of Evil.
He has appeared in other media based on DC Comics properties, such as Justice League War, where he voiced Superman, Powerless, playing the role of Bruce Wayne's cousin Van Wayne, and Doom Patrol as the first season's main antagonist, Mr. Nobody.
- Heath Ledger and Alan Tudyk starred together as main characters in the film A Knight's Tale, and subsequently, both actors have played The Joker in different installments of the Batman franchise. Ledger is remembered for his role in Christopher Nolan's film The Dark Knight, while Tudyk voices Joker on Harley Quinn.