This core rulebook for Dungeons & Dragons features advice and rules for Dungeon Masters of all levels of experience, with a particular focus on running adventures and campaigns in the paragon tier (levels 11-20). It includes advanced encounter-building tools (including traps and skill challenges), storytelling tips to bring your game to life, new monster frameworks to help you craft the perfect villain, example campaign arcs, a comprehensive look at skill challenges, and a detailed 'home base' for Paragon-tier adventurers - the interplanar city of Sigil.