Small ships that attack in swarms, considered disposable by most commanders. They are usually armed with lasers, missiles and a dust shield. For long range attack a fleet will launch from a destroyer at long distance from the target, and maneuver to launch attacks from several angles. When in position, they fire small missiles that are difficult to detect and intercept. The swarm ships will follow the missiles and engage in short range attack after the missile wave. Short range attacks usually involve firing everything as fast as possible and then attempting to ram the target.

Swarm ships are never manned during an attack and are usually built as small and simple as possible. Some of the larger designs do have a passenger cabin, and can be used as scout ships or light transport. Most designs are a simple spherical ship, typically twenty to forty metres across, though other designs are used, both smaller and larger.

Swarm ships are widely used for defence. Fleets can be place in orbits around stars and planets, along expected attack trajectories. Operating in low power mode, these fleets can orbit for many years "waiting" for an attack. Swarm ships are also used for defence on habitats. Fleets are stationed on the habitat, ready to launch when needed.