Torpedo!, Tactical Submarine and Anti-Submarine Warfare, 1939-1945. This is the submarine expansion for the tactical World War II air-naval series from SimCan. The other games in the series are IJN, Kriegsmarine, and Schnellboote.SimCan says: 'Special rules cover the actions of submarines, convoys, ASW aircraft, mini subs, and even ASW blimps. The weapons of Japan, America, Netherlands, France, Canada, Russia, England, Italy, and Germany are included and scenarios range from one on one sub vs. destroyer actions to combined sub, surface, & air actions against the Murmansk runs.' - BoardGameGeek