The Thalas Sea (IPA: /ˈθæləs/), also called the Sea of Stars, is the vast expanse of ocean that lies between Epiros and Anatios. A notoriously stormy place, crossing the sea requires many weeks of sailing with a highly experienced crew and a very seaworthy vessel.

It is said that there are a great many strange islands scattered throughout the sea, but few have ever returned from expeditions to locate them. Those that have speak of bizarre islets peopled by outlandish "bird-men", and other unusual creatures, almost all of them extremely hostile to intruders.