Dungeon World: Exodus
Many years ago a barbarian named Grond came to wage war against Exodus. Rather than face him in battle, one of the quints was abandoned to make room for him and his horde.
Officially the war still rages, but the barbarians and mercenaries have grown complacent with their position and comfortable with the taken amenities.
There is trade with the district, albeit fairly small. Many youths from this district get arrested for trying to raid their nearest neighbours.
The barbarian lord Grond is still alive and well, often seen patrolling the walls already installed and constructed by his people. He was human once but has grown a cracked red skin not unlike stone. He is a few hundred years, but hasn’t shared the secrets of his longevity.