Battlefleet: Pacific War 

Naval strategy game, extension to the classic Battleship game where ships/planes/subs can move! Game contains missions, Death-Match and Free Hunt scenarios & campaigns from Pearl Harbor and Midway to the Iwo Jima and Leyte battle.
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Submarines for Mac 

You're the captain of a ship moving through a mine field. Use your depth charges to destroy the enemy subs laying those mines before one blows a hole in your hull. Watch out for the sea creatures. Some can help but others just get in the way.
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