The Ouroboros is a fighter ship discovered by the survivors of the Terran Union's massacre that uses both positive and negative energy polarities allowing for the ship to not only absorb energy, but drain it from enemy fighters before overloading their engines.
The legendary energy polarity tech (deriving from the yin/yang polarity theory) came from the Edenians, an ancient race that existed in the Old Kingdoms but was said to have been eradicated by the Cythas Incident.
The ship is now piloted by The Child of Eden who uses it to fight against various mechs, drones and battleships that are used by the Terran Union.