The Knautilus is a particular submarine operated by Baron K. Roolenstein (King K. Rool in disguise) and it is where Dixie Kong and her cousin Kiddy Kong battle him for the final time. It is found in the land of Krematoa and is featured as the final level in Donkey Kong Country 3: Dixie Kong's Double Trouble!.
The exterior of the sub resembles a fish while the interior contains missiles, a ship's wheel for steering, two large inbuilt radars, two hatches, scuba suits, torpedoes, vents, control panels and five generators. It also contains traps such as fireball cannons, four giant electrical nodes and a conveyor belt.
Baron K. Roolenstein, with the aid of of his minions, designed and used for other purposes rather then mere seafaring, such as hunting for treasure, or collecting lost weapons & mechanical scraps, or spying, or tracking down enemies. & he will do so without hesitation.
When K. Rool was defeated in Kastle KAOS, he falls down a wooden well and escapes in his submarine.
The Knautilus later appears in Krematoa's central lake when Boomer starts a machine which activates an volcanic eruption.
- The name is a pun on the name shared by both the Nautilus submarine (from the the novels Twenty Thousand Leagues Under the Sea and The Mysterious Island), and Ursula's Necklace (from Disney's The Little Mermaid).
- If the Steel Keg absorbs the electricity, the game can be paused and then undone for it to be done quicker.
- If the player pauses it while the electricity is still airborne, he/she loses a Kong or a life.
- The GBA version's intro of the game could possibly be a depiction of how Donkey Kong and/or Diddy Kong were captured by the Kremlings, since the intro starts with a P.O.V. shot of someone wearing a diving mask, which ends with the Knautilus closing in and "swallowing" the camera, and then the next shot shows the Knautilus rising out of the water.