The Vaelorin Sailwing is a large coastal flying reptile native to the eastern shores of Mediath and the surrounding Erynic waters. Adults possess long narrow wings, a toothless bill, and a distinctive backward-pointing crest. Large males commonly reach wingspans of five to six and a half metres. Sailwings spend much of their lives soaring above the ocean in search of fish and other marine prey, returning in enormous numbers to cliffside rookeries and offshore islands to breed.

The great Vaelorin rookeries are also economically important. Generations of nesting sailwings produce deep deposits of nitrate-rich guano in sheltered caves and ledges, which are mined for saltpeter used in gunpowder, explosives, chemical work, and fertilizer. Many of the largest colonies are consequently protected and carefully managed, with extraction carried out outside the principal nesting season to avoid driving the animals from the rookery.