Bliking

The Bliking is Wapol's ship. The Bliking has the ability to submerge underwater, although how this is achieved is unknown. Chess would stand on top of it while it was submerged, making him appear as if he was walking on water. "Blik" is Dutch for 'steel plating'. So far it is the only submersible ship in One Piece, not counting the Shark Submerge III from the Thousand Sunny.