The vast ocean filling up most of the globe, surrounding the Continent and the Southern Seas, is known as the Stormwrack Ocean, the Great Ocean, or simply the Stormwrack. It is three times the length of the Continent to travel by sea across it from Cerulean to Sunderwyl, and some brave madmen have managed it, dodging terrible storms and titanic leviathans to conclusively prove that the world is round.
While the Stormwrack is no different qualitatively in composition or depth from the seas around the Continent or within the Southern Seas, the sheer scale of it makes it behave like an entirely different beast. Hurricanes that blow up in the center of the ocean continuously gain strength as they travel, and there is no land to weaken them for thousands of miles. By the time they hit the Continent or the Stormbreakers of the Southern Sea, they are hypercanes: larger than Sundland, pouring a foot of rain in a minute, with winds able to effortlessly lift a mortal off their feet and topple buildings fashioned of stone. Ships that find themselves in a hypercane’s path can only hope to outrun or dodge it, for the storms have no mercy; even if a vessel manages to avoid capsizing, the winds are strong enough to rip the planks off its deck to get at the terrified mortals inside.
Similarly, the sheer size of the ocean means that it is able to support massive amounts of sea life, much of which grows to terrifying size. Though many have attempted to catalogue all of the beasts and fishes that grow within the Great Ocean, new species are continuously being discovered, either by the brave and foolhardy hunting vessels that sail beyond the safer bounds around the Continent and Southern Seas, or by corpses washing up onto the shore somewhere and being discovered by locals.
Islands exist within the Stormwrack, though the few that have been charted are rocky knobs and wind-scoured reefs rather than anything a mortal would consider livable. There continue to be legends of the great island-nation of Atlantis somewhere out in the midst of the Great Ocean, filled with mortals who fled the Old Gods’ empires before the Godswar, but so far no scholars or adventurers have been able to find proof of such a civilization’s existence.