Custom built sister ships designed with divers in mind I stayed aboard one of these custom-built sister ships, which were definitely designed with the diver in mind. Both vessels are 85 feet long and can run at 8 to 10 knots. Each stateroom boasts plenty of space for two and has a private bath. The Aggressor I runs the northern itinerary that includes Darwin and Wolf Islands. Nitrox is available. The Aggressor II runs the southern itinerary including Espanola and Florena islands. To book a trip or for more information, click onto the Aggressor Fleet home page below.