Hyades is a jungle world in the Segmentum Obscurus not far from the death world of Fenris that is a holding of the Navigator House Belisarius and is protected by the Space Wolves Chapter of Space Marines because of the ancient alliance between those two Imperial factions. Hyades is unusually rich in naturally-occurring promethium, which is why the wealthy House Belisarius invested heavily in the exploitation of the fuel on Hyades and sponsored the settlement of an Imperial colony on the planet. Hyades is a hostile planet with large predators and an indigenous reptilian Xenos species called "Reptos" by the Imperial settlers. The jungles also grow at an exceptional rate, requiring that they be burnt or cut back at all times to avoid them encroaching on the human settlements. Even so, Hyades