From SporeWiki, the knowledge base dedicated to Spore
Draco scouts are very small, fast, and maneuverable craft with a single, two barrel proton cannon. These crafts, often called darts, are very difficult to maneuver, and only the most experienced pilots can fly them. Darts are primarily used for scouting missions, but can be used for quick strikes against beat down units or buildings. Another tactic is to have numerous (20 or more) Darts swarm a slow moving ship such as a transport or siege ship. Usually ships equipped for sieging cities cannot shoot fast enough to pose a threat.