Athonos

Athonos is a Tempestus civilised world whose dozens of rival families wage unending gang war through the streets and sewers of its hydroponic gardens, which is exactly why the tithe can raise Athonian Tunnel Rats. Those Guard are close-quarters hive and mine specialists, not line infantry from a parade world. Late M41 the Necron pirate-king Thaszar woke under the capital, lifted a tomb ship through it, levelled the city, failed to notice the humans were people, and left after swatting an Eldar listening post in orbit.