In one of the dimensions of the multiverse one of the Great Races decided to simply destroy the inhabitants of Earth, even if it meant the planet was rendered inhabitable. This has since been lamented, as the energy from the blast was channeled by certain individuals and a new breed of terrans was created. there was only 10,000 of them, but with the powers they possessed no one saw it as a good move to attack them on the worldship (not actually the size of a world, but world as in it was built to be a permanent habitat) they live on.