The Mo Ce Sea (literally "lonely sea") is an small open body of water between the Earth Kingdom and the Fire Nation. It extends from the Hu Xin provinces of the Earth Kingdom to the Crescent Island, and from the Fire Nation islands to the western coast of the Earth Kingdom. It factors as a location for major naval incidents and is most notably the home of Crescent Island and Roku's Island. The Mo Ce Sea has seen countless naval battles during The War.