Much like Earth, Aserra has more ocean than land. This was increased after the sinking of Ageond in the War of the Gods. This cataclysmic event first caused shorelines around the world to retreat, and then led to a period of global warming due to volcanic activity and changes in ocean currents that freed up water frozen in the polar ice-caps, which attributed to a rise in sea levels. At present, Aserra's climate is stable.
Aserra’s largest ocean is the Tonult, which covers much of the world’s western hemisphere. The Tonult is between the western coast of Thiskel and the eastern coast of Kalesten. It once stretched between Kalesten and Ageond, but when Ageond was destroyed during the War of the Gods, it sunk beneath the Tonult and joined the ocean with the Sea of Otore that used to lay between Ageond and Thiskel.
The Forsaken Land and remaining archipelagos that were once Ageond’s mountains are now islands in this vast ocean. Tonult’s oceanic borders are considered to be the arctic and antarctic circles, directly south from the southernmost point of the Forsaken Land, north of the narrowest point between the Forsaken Land and Thiskel, and directly south from the southernmost point of Kalesten. Due to the size of the Tonult, it spawns ferocious hurricanes and tropical storms that plague the islands and coasts of Kalesten and Thiskel.
Another effect of the sinking of the continent was the destruction of a ley point in north-central Ageond. This region is known as the Ageond Quadrangle which is now a stretch of open sea where the leypoint once was and is considered dangerous and intractable. All who traverse the oceans avoid this region, sticking to skirting the safer island chains. The Quadrangle is a place of chaotic, unpredictable energies that have caused mysterious disappearances and mishaps to travelers who pass through it.
Sea of Lertura
The arctic ocean of Aserra is the Sea of Lertura, which is mainly contained within the arctic circle. The continent of Athok and the arctic ice cap are contained within, and it borders the northernmost reaches of Thiskel and Kalesten.
Sea of Kaltur
The antarctic ocean is called the Sea of Kaltur. There is no land here, but there an ice cap, though it is smaller than the northern ice cap. Without land beneath it, the ice can be particularly treacherous for sailors. For the most part, the Kaltur is untouched by any of the races. Ships skirt the outer edges to circle around the southern cape of Thiskel, and fishing vessels from the Forsaken Land sometimes follow fish to the outer edges of the sea, but the ice flows are a major deterrent from going too far in.
The Riath Sea lays between Thiskel and Kalesten, and is little more than a broad strait in some places, making travel between the two continents quite easy. The Riath’s borders are considered to be the arctic and antarctic circles, then directly east from the southernmost point of Thiskel to west of the southernmost point of Kalesten.
Sea of Otore
The Sea of Otore is the remnant of the narrow sea that once ran between Thiskel and Ageond. It now only lies between the Forsaken Land and southern Thiskel, as the northern region joined the Tonult after the sinking of Ageond. Otore’s borders are considered to be the narrowest point between the Forsaken Land and Thiskel, from the southernmost point of the Forsaken Land eastward to the southernmost point of Thiskel westwards, and the southern border is the antarctic circle.
Sea of Thiskel
The Sea of Thiskel is the large inlet that lays between northern and southern Thiskel. Its border with the Riath are considered to be a line diagonally northwest of the tip of the northernmost peninsula of southern Thiskel to the closest coastline of northern Thiskel.
Sea of Kalesten
The Kalesten Sea is the region of sea within the hook-shaped northern continent of Kalesten and its sub-continent of Ertia. Its oceanic border is considered to be a direct line from the southernmost point of Ertia to the tip of the eastern peninsula of southern Kalesten.
Sea of Athere
The Sea of Athere is formed by the east coast of North Kalesten, northern coasts of Ertia and the archipelago to the northeast of Ertia. It connects to the Sea of Lertura and Tonult, through the islands.