Danger Beyond the Stars
Feral World at the mouth of a stable Warp Corridor
Ar-Niggurath is a craggy feral world that looks like something that belongs in a pulp novel.
Ar-Niggurath is at the head of a stable Warp Corridor. Control Ar-Niggurath and you control the warplane. This makes it a high-priority, given the circumstances.
Despite the relative primitivity of the inhabitants they can and often do, make suprisingly large scale war and build rather large temples to Emp-Rar.
No discernible Imperial Presence other than a few automated monitoring stations in orbit tasked with looking out for xenos.