The Plesiodragon is a deep water dweller, spending most of its life underwater. They rise to the surface to breathe air, storing huge amounts of oxygen to enable them to stay underwater for long periods of time, even sleeping for short intervals underwater. They hunt and navigate the dark depths using echolocation, using a complex burst of clicking sounds. They are graceful underwater, using their flippers to literally fly through the water, or just cruising the deep depths, but when on land they can appear clumsy, the flippers allowing only limited mobility. They can only stay out of the water for a day maximum, needing to drink plenty of water as they quickly dehydrate. These gentle giants are the biggest dragon species found so far.