From the introduction: Ptolus is meant to be fantasy role-playing in microcosm. It embodies all that is fundamental to the genre, but it does so in the space of a single city. That means there are dungeons to explore as well as townsfolk to interact with. There are strange magical mysteries to discover, demons to fight, and even dragons. Ptolus is truly a city of adventure—player characters don’t have to leave it to embark on amazing adventures.