Genestealer cult discovered in Menthoteph

In late 11.018M42 the imperium still only had a tenuous hold on the outskirts of Praxis, but had found that a set of catacombs underneath the city led to Menthoteph. Having failed to deal with the chaos forces in the city ruins, the Grey Knights now turned their attention to the ruins of Menthoteph, where the imperium had already established a foothold. Their investigations of the ruins turned up an unexpected discovery, that genestealers of the foul Tyranid xenos strain were still present on Hexis, and the astartes began the important task of clearing the aliens. Despite their vicious assaults and tending claws, the xenos infestation was overcome, and the Grey Knights secured the centre of Menthoteph - only a small area still patrolled by the eldar now held out against the imperium. Below, the dark catacombs were still held by the awakening necrons, but through those a new path to the device room would be available for the all conquering imperium.