Deeper

The Deeper are a type of Mutant, that dwells in the depths of Necromunda's Hive Primus.

They are originally descended from foolish holesteaders, who tried to make a life in the fungal depths of the Hive's bottom. Centuries later, that environment changed them so that the Deeper now have hairless ratlike skulls, skin the color of pus, black eyes that look like lumen globes and are also both taller and thinner than other Mutants. They have since become a stable-strain of mutation, but are not yet classified by the Imperium as being Abhumans.

They kind of sound like Rat People, which, given the Rat God of the Ratskins dwells on Necromunda...