P.T.O. IV (Pacific Theater of Operations IV) released as Teitoku no Ketsudan IV (?????IV) in Japan is a World War II-themed strategy for the PlayStation 2 and PC produced by Koei. It focuses on naval combat in the maritime theaters of World War II encompassing the Pacific Ocean Mediterranean Sea Atlantic Ocean and Indian Ocean with the option of playing as one of four major maritime powers of the time: Germany Japan the United Kingdom or the United States. P.T.O. IV is the latest game in Koei's P.T.O. series.