Derillium mines were proximity space mines that were activated when an enemy ship approached. Derillium mines where deployed in limited numbers due to their destructive force. When a ship passed within a predetermined range, ranging anywhere from 0-100 meters, the mine would explode violently with enough force to destroy even the toughest starfighters, and cripple larger star ships. The Galactic Empire had planted such mines along the Arah asteroid belt in order to protect the Arah mining facility from intruders and spies.
Due to a minor programming bug, two mines laying next to each other, one could destroy the other if an experienced pilot quickly passed between them.