Jolly-Go-Jumbo fish are a kind of fish that can grow rapidly in size. They first appeared in "Free Teensy".
Jolly-Go-Jumbo fish are colored gold-yellow. However, each of them has a ring around one of their eyes with a different color.
In the show
In "Free Teensy", Jolly-Go-Jumbo fish are offered as prizes with other fish at the Jollywood carnvival by tossing a ring to the top of a bowl. Queen Delightful tries her hand at it and win one, who she names him Teensy. Grumpy, who was in charge of the game booth, receives a warning from a man a few times throughout the episode who seemingly has knowledge about Jolly-Go-Jumbo fish. At the castle, Queen Delightful and Lord Starchbottom noticed that Teensy began to outgrow several bowls (even a tub) of each size, forcing him to move to the moat (and swallowing Grim and Hildy, who was looking for the shape-shifting ring Teensy swallowed earlier). With the help of The 7D, Teensy made the ocean his permanent home, and began to fall in love with another Jolly-Go-Jumbo fish that was separated from each other earlier at the carnival. Soon after, other Jolly-Go-Jumbo fish owned by some residents of Jollywood became gigantic and destroyed their roofs.
- The Jolly-Go-Jumbo fish are also named Fishimus Largimus (as Doc said when he told the queen what she was dealing with).