Currently, rampaging monsters heading to settlements that are on regions above your own civ level spawn at the level of the region. I am level 15, but dared to nab a settlement in a level 24 region, leading to rather... challenging rampaging groups. After dieing to one of them once and not feeling too big on dealing with the vengeful spirit as well, I paid them off.
But paying them off, while causing them to stop moving, still lets them stay in that region tile.
And for some reason, for that settlement, they all approach from the same direction too.
I'm now up to 12 bosses (8 amoebas, 1 vengeful spirit, 3 espers), 11 of which are 9 levels above my civ level in the attached screenshot. Just look at that minimap.
Having to go to strategic map every time I advance a turn to make sure that I don't miss another group spawning and advancing on that same location is getting a bit silly.
What do I do about this? D: