The Wurm planned to take over the home planet of the peaceful Valnaxi which, due to its position, would allow them to conquer the rest of the galaxy. The resulting war grew to span the seventeen systems of the Wurm Empire. Through the Tenth Doctor's intervention, King Ottak was killed and the Valnaxi ship was sent into space by a volcanic eruption so the fighting would leave Earth. The male and female stayed behind. (PROSE: The Art of Destruction)