Originally a production of Blue Sky Studios, the film was cancelled following Disney's shutdown of the studio in early 2021. At the time of its cancellation, the film was reportedly 70% finished in Layout. The film was revived by Annapurna and Netflix the following year. DNEG Animation completed all visuals for the finished film, including the titles, animation, and End Credits.
Based on graphic novel Nimona by ND Stevenson.
Eugene Lee Yang was the only actor to read for Ambrosious Goldenloin, after the production designer suggested his name for the character to be modeled after, and was then sent an audition.
At 32:36, when the commercial for Dragon Krisps cereal plays, the theme used is the "Tra-La-La Song" theme from The Banana Splits Adventure Hour (1968), a Saturday Morning Children's Show developed by Hanna-Barbera for NBC.
In the graphic novel, Ballister's last name was Blackheart instead of Boldheart, and he was originally more villainous and actively trying to take down the Institution. Also, he had lost his arm in a duel with Goldenloin, not from the latter trying to disarm him.