Beneath the shadows of that ancient and dread place men call Castle Zagyg stands the fortified town of Yggsburgh. Its stout walls and cobbled ways give ample refuge to those bold and worthy adventurers who come to the Four Tors to plunder the dungeon deeps of the Mad Mage or die valiantly in the effort. Binding the walls, are the Urt and Nemo Rivers, whose tumbling waters stretch the length of the lands beyond the Four Tors, Castle Zagyg and Yggsburgh. In these hinterlands are marks of the Mage in such places as the Oldoaks Grove, Glittering Knobs, Uplands and the Lonely Valley. Enter the environs of that most dread of magi, test your metal and make ready for the heroes forge that is Castle Zagyg! Yggsburgh is an introductory setting for Castle Zagyg proper. Yggsburg is designed for 4-8 players of mid to low level. Beyond the town proper are detailed over 30 encounter areas. Yggsburgh comprises 1500 square miles of adventuring terrain, complete with all the information players and DMs need.