Sanctum - Heart: The City Beneath RPG

Sanctum - Heart: The City Beneath RPG - Rules of Play says:

SANCTUM is a sourcebook for the Heart RPG. Inside, you’ll find a guide to building havens with your group to create the basis for an exciting campaign. You’ll also find advice on running haven-based campaigns, special fallout results that reflect your settlement’s trials and tribulations and ways to create and reinforce bonds with the people within.