The following is a list of characters featured in Kamp Koral: SpongeBob's Under Years. Please note these characters have also appeared in its parent show, SpongeBob SquarePants, as well as it's sister show, The Patrick Star Show.
Main characters[]
| Image | Name | Voice actor | Description |
|---|---|---|---|
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SpongeBob SquarePants | Tom Kenny | A ten-year-old sea sponge who is the most enthusiastic camper at Kamp Koral. |
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Patrick Star | Bill Fagerbakke | SpongeBob's best friend and bunkmate. |
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Squidward Tentacles | Rodger Bumpass | A slightly older camper. He is practicing to be a junior counselor. |
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Sandy Cheeks | Carolyn Lawrence | A squirrel from land who joins the camp by living in an enclosed glass treehouse. |
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Eugene H. Krabs | Clancy Brown | The camp director who spends his time taking care of his baby daughter Pearl. |
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Pearl Krabs | Lori Alan | A baby whale who lives with Mr. Krabs in their cabin. |
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Mrs. Puff | Mary Jo Catlett | The scoutmaster and arts-and-crafts teacher of the camp. |
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Sheldon J. Plankton | Doug Lawrence | A camp chef who secretly has a lab full of inventions. |
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Karen Plankton | Jill Talley | Plankton's assistant, a talking calculator who moves around in a pink rollerskate boot. |
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Gary the Snail | Tom Kenny | A stray snail who befriends SpongeBob and becomes his pet. |
Supporting characters[]
| Image | Name | Voice actor | Description |
|---|---|---|---|
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Narlene and Nobby Narwhal | Kate Higgins Carlos Alazraqui |
Two narwhals who usually hang out in Kamp Koral and mess around with SpongeBob and his friends. |
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Larry the Lobster | Doug Lawrence | A muscular, weight-lifting lobster who is a troop leader of the Frigate Cabin. |
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Bubble Bass | Dee Bradley Baker | A overweight bass who is a troop leader of the Pontoon Cabin. |
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Perch Perkins | Dee Bradley Baker | A ranger of Kamp Koral who makes announcements. |
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Kevin C. Cucumber | Dee Bradley Baker | |
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Harvey | Carlos Alazraqui | |
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Craig Mammalton | Dee Bradley Baker | |
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Mo | Sirena Irwin | |
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Tall Tail | Tom Kenny | |
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Missy Upturn | Sirena Irwin | A rich woman who is a troop leader of the Yacht Cabin. |
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Roh and Rea | Bill Fagerbakke and Carolyn Lawrence | |
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Regigilled | Rodger Bumpass | An octopus who is Lady Upturn's butler. |
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Kidferatu | Dee Bradley Baker | A kid version of Nosferatu who is a troop leader of the Trawler Cabin. |
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Jimmy Blobfish | John Gegenhuber | |
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Preda Tory | Grey DeLisle | |
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Roxy | Grey DeLisle (Big Roxy) Kate Higgins (Little Roxy) |
|
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Elwood | Grey DeLisle | |
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Nurse Helga | Sirena Irwin | |
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Wise Kraken | Brad Garrett | |
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Anchovies | Various |
Returning characters[]
| Image | Name | Voice actor | Description |
|---|---|---|---|
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Flying Dutchman | Brian Doyle-Murray | |
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Cecil Star | Thomas F. Wilson | |
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Bunny Star | Cree Summer | |
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GrandPat Star | Dana Snyder | |
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Mermaid Man and Barnacle Boy | Tom Kenny | Two younger superheroes fighting against crime and evil. |
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Man Ray | Bob Joles | |
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Dirty Bubble | ||
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Jumbo Shrimp | ||
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Atomic Flounder | ||
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Sinister Slug | ||
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Dorsal Dan | Steve Buscemi | |
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Sticky Fins Whiting | Joe Pantoliano |