Submarine warfare from post-WW2 to the present day! Lay mines, strike land targets with cruise and ballistic missiles, creep up to surface ships to take hull shots undetected, sniff sensitive electronic emissions, tap undersea communications cables, covertly deliver special-forces teams ashore, and of course hunt down anything on the sea surface or underneath it, using an array of torpedoes, missiles and other means. The depths are your domain - and your playground.