The Nasgul are a species that is actually comprised of six different races. The different Nasgul species were extremely similar in their functionally-important DNA, sharing over 99.5% despite the apparent physical differences. All the Nasgul species shared distinctive ridges on their cheekbones and foreheads. Their lungs are also capable of adapting to the atmospheres of any planet or ship. For One Thousand years after the destruction of their homeworld due to a thermonuclear chain reaction deep within the planet's unstable core, they have lived in large starships. Hope came when they sent a ship to several worlds that would be fit for colonization. However, one of the ship Unities teenagers, a young insectoid, accidentally sent the ship into a wormhole, killing most of the crew until there were only the Twenty teenagers left. They now live on the Earth Ship, the Columbia.