Knautilus

The Knautilus is Baron K. Roolenstein's submarine docked inside the lost world Krematoa during the events of Donkey Kong Country 3. This submarine is fish-shaped, and K. Rool hides here after he is defeated in KAOS Kore.

Summary
This area is accessed once all the Krematoa levels are completed. With the five cogs, Boomer uses them to activate a machine which causes Krematoa to steam; its waters turn red and the Knautilus is revealed in the center of the lake.

Dixie and Kiddy Kong enter through the roof of the submarine, and inside, they find K. Rool, whom they have a final showdown with. The Kongs both collapse onto a conveyor belt area, with electrical machines located on both sides of it. K. Rool controls these machines, as seen in the foreground. If his machines are successfully avoided, a Steel Keg appears and a big vacuum in the roof opens. K. Rool is damaged if the Keg is thrown up the vacuum and hits him when it comes out the other side.

The Knautilus appears in Donkey Kong Country 3's Game Boy Advance remake's intro and title screen.

Trivia

 * "Knautilus" is a pun on the submarine Nautilus from the novel "Twenty Thousand Leagues Under the Sea".