A FRIGATE is a type of war vessel that is typically used for protection and escort duties. It is usually a medium-sized, fast warship with a single gun deck. A Uboat is a type of German submarine used during World War II. It was designed to operate in the North Atlantic Ocean and other waters. A RAIDER is a type of warship that is used for attacking enemy vessels. It is usually smaller and faster than other warships and is designed to surprise and outmaneuver its opponents.