Main plot hook : Landslide in a mountain pass has revealed the ruins of an ancient city of some kind, but due to remote location a caravan is being set to establish a base camp for explorations into the ruins. Player characters would not only be the man exploration team, but would have jobs in the newly established settlement, too. GMs/DMs would need to create at least a rough map of the underground city, and then try to keep up with a constantly changing map for the settlement that grows from the community supporting the exploration while also adding details to the ruined city map as it's explored.