Captain Metal's submarine was a unnamed submarine used by Captain Metal in pursuit of Blaze the Cat, her friends, and his double crossed crew members Bean the Dynamite and Bark; with Swash and Buckle as his crew-mates. He later appeared in the submarine in catching the last Sol Emerald after the destruction of the Kraken, and thus led to the ensuing attack. Eventually, Swash and Buckle abandon ship and swam all the way back to Pirate Island when they had enough of Bean. This allowed Marine and Bark to take the Submarine when the Metal Marauder was sunk by Captain Whiskers. After defeating Captain Metal and saying their teary goodbyes (at least in the case of Marine) to their friends, Marine and Blaze then used the submarine to make their way home. (SU: #57, #58)
As with any submarine, Captain Metal's was capable of traveling underwater at great distances. It is unknown if it is equipped with any sort of weapons.