The Eusian Sea is the vast expanse of ocean to the east of Sapience. Within it are such places as the isle of Ulangi, the pirate port of Mysia, the island temple of Oneiros, the Nerai isle of Eithekos, and, deep below the waves on the edge of the continental shelf, the meric city of Riparium. It is watched over, naturally, by the ocean spirit Eusia.