Heart Pirates' submarine

The Heart Pirates' submarine is the as-of-yet unnamed submarine used by the Heart Pirates.

Appearance
Despite the fact that it works like a submarine, its design is similar to a ship as it has a mast and lamps on the outside. Also, on the side of it is the Jolly Roger of the Heart Pirates.

Trivia

 * This is the fourth ship in the series to be a submarine, the first being the Wapol Pirates' Bliking, the second being the Straw Hat Pirates' Shark Submerge III, and the third being the anime only Amigo Pirates' unnamed ship.