Maritime Channel 

"Your mission is to protect this maritime channel by every means possible. You have to destroy all enemy war ships that are trying to cross the channel. Thousands of Free Online Games, Free Flash Games, Free Games at factorygames.com"
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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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