The thing about characters who are going to be constantly running hostile actions is just plain attrition. They hit retreat after retreat, and even if they run only 5% losses per engagement, they will be depleted in a manner of time, if they are 'recruiting and drafting' people in the interim, then it is just a matter of time before mini-darwinism puts the tough guys vying for positions of power in such a super aggressive group at each others throats before long as they fight to sort out their own pecking order.

Also realize that certain aspects of forensic knowledge and ability are never going to go away. Some social order will eventually be restored or built from scratch, and someone really rolling around doing human rights violations will probably either have to be in hiding or answer for it someday.

Likewise, someone who decides to engage in summary ambush and execution of refugees, even armed refugees might stand a better chance of longevity, but I think at some extent, some of us will be keeping track of which envoys and refugees heading into or across which areas are disappearing and which are not.