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.

Abilities
The vessel seems to display considerable speed and maneuverability when submerged, as seen when it completely outpaced Aokiji's Ice Age, and evaded Kizaru's Yasakani no Magamata.

And from the inside, the submarine seems to be well-equipped with medical apparatuses and life-supports systems all stored in the sick bay.