Knautilus
The Knautilus is a large, wooden submarine which belongs to the evil Baron K. Roolenstein.
Not much about the Knautilus is revealed, such as the full extent of it's abilities or weaponry, if it possesses any at all. Inside the Knautilus is a large conveyor belt located on the floor of the submarine, as well as a cannon that can launch fireballs. Large, circular devices on the walls of the Knautilus are also shown to shoot electricity.
The Knautilus is where Dixie Kong and Kiddy Kong's final battle against Baron K. Roolenstein takes place in Donkey Kong Country 3: Dixie Kong's Double Trouble and Donkey Kong Land III; where, in the former, it is located in Krematoa, while in the latter, it is found in the Lost World.
The Knautilus also appears in the opening cinema of Donkey Kong Country 3: Dixie Kong's Double Trouble's Game Boy Advance remake, where appears just before the game's title screen; here, the Knautilus opens it's front end just before propelling itself at the screen, giving the illusion that it has "swallowed" the screen.