@akula2ssnI wouldn't say that it was a hasbeen world. Instead, id say it should be fairly wealthy, which only raises the stakes. So that everyone's trying to get to it... which breeds paranoia.
Due to the local area being destabilized with the death of Cadia, our planet has been sent a few regiments of foreign imperial guard. The locals dont like these foreign intruders, but the Planetary Governors propaganda says they are there for security. They are infact there as a staging area for a counter-attack on the forces flooding out of the eye of terror, meanwhile the indomitus crusades is no where to be seen... this is worrying because everyone is wondering where they are...
One such regiment is the 50th Havelock Brutalists.
Their special issue gear is urban chemilioline great coats with sewn in flak armour. They also get close support by sentinel powerlifters per squad armed with the power lifter of course but also an underslung chainsword. The best way to describe how they employ these is brutality. They use the power lifters for counter charges and on any of the imperiums more melee oriented enemies. They are grenadiers and have just been relocated after a victorious battle fighting Orks. This Regiment is known for taking battle trophies from their foes, such as horns and fangs. Infact the squad leader is usually selected based on how many fangs they have collected. They are selected from the planets warrior caste.