Daikoukai Jidai IV: Rota Nova

Uncharted Waters, originally released as Daikoukai Jidai (大航海時代, Daikōkai Jidai; "Great Age of Sailing"), is a Japanese business simulation/strategy/role-playing video game series produced by Koei under its "Rekoeition" brand, themed around seafaring adventures during the Age of Discovery. In the games, the player takes up the role of a captain (or commodore in some translations) and manages a seagoing fleet to participate in trades, privateering, treasure hunting, exploration and plain piracy. Even though the series is largely open-ended, there is still a loose plot which requires the player to follow certain paths, and deviating from these paths may stall the progress of the story.