A DESTROYER is a large, fast warship with nine letters. It is typically used for escort and patrol duties. A CRUISER is a large warship with seven letters. It is usually used for scouting and long-range missions. A FLEET is a group of warships with five letters. It is usually composed of several different types of ships. A TRIREME is an ancient warship with seven letters. It was powered by three banks of oars and was used in the Mediterranean Sea during the classical period.