Uncharted Waters Online, originally released as in Japan, is a MMORPG developed by KOEI based on the Uncharted Waters series of games. Set in the Age of Exploration, it features over a hundred different sailing ships and an open world based on real Earth geography. With a sandbox style game play and skill based character development, players interact with each other and engage in many activities such as combat, exploration, and trade on both sea and land. The game requires monthly subscription fee in Japan but the international server is free to play.