Elline transforms Kirby into Kirby Submarine for a river patrol. The hero is frequently ambushed from above and below by bomb-tossing Dangle Sloths, green Blippers, and falling Gordos. Kirby Submarine must move up waterfalls and aim carefully to get through the stage.
- Kirby Submarine figurine
- "Bubbly Clouds" music
- Dangle Sloth figurine
- "Big Forest" music
- Waddle Dee (Submarine) figurine
- One music track exclusive to Deep-Divin' Kirby Submarine is titled "Watch Out for That Sloth." This name may be a reference to the 1967 animated series George of the Jungle, as "watch out for that tree!" is a famous line from the show's opening theme.