Many centuries ago, the dwarven kingdom of Sarphil stretched out across the Galena Mountains east of the Moonsea. They dug for the precious metals hidden beneath the rocky terrain, and they established numerous cities and settlements to aid in their excavation and manufacturing efforts. This was during the early days of Myth Drannor, the elven kingdom in the forest of Cormanthor, and the dwarves and elves initially clashed as each sought resources and expanded their territories. Myth Drannor and Sarphil eventually settled their differences, and many dwarves moved into the elven city to offer their services and expand their knowledge. In the Galena Mountains, Sarphil continued to flourish. Unfortunately, these days of prosperity did not last long. The last great king of Sarphil was lost in the dwarven city of Mount Throndor, beneath the mountain peak of the same name, and Sarphil withered under bitter clan disputes since no single family could claim legitimate lineage over the fragmented kingdom. What happened under Mount Throndor has been a mystery for thousands of years. Many attempts have been made to reclaim the lost riches and legacy of the last Sarphilan king, but powerful wards have prevented intrusion under the mountain, wards erected by the dwarves of Sarphil. Were the wards built to keep outsiders from intruding – or to keep something inside from escaping? An enterprising dwarven leader wants to find out, but she is going to need some help from a band of heroes. Horrors of Mount Throndor is a Dungeons & Dragons adventure of exploration, darkness, and terror featuring a lost dwarven city overrun by forces from the Far Realm and the journey to cleanse it once and for all. The adventure is designed for a group of 11th-level characters, and successful completion of the adventure should put the characters at 16th level. Here There Be Monsters Mount Throndor has become infested with madness from the Far Realm. During their journey to penetrate the ward and through the city itself, the characters are going to face gibbering horrors, unpredictable slaadi, fanatic stone giant cultists, degenerate star spawn horrors, mutant derro, undead dwarves, and countless golems. The ancient breweries of Mount Throndor have produced alementals who slither in the darkness, and a great dwarven war juggernaut named Big Hans stomps through the city. Legendary Villains and Epic Moments Though it has been sealed, Mount Throndor is not empty. The characters have opportunities to meet, interact with, and (likely at least) combat against powerful foes within the legendary dwarf city. A dwarf lich, a Far Realm spider goddess, an iron-encased demilich, and a melted flesh derro warlock monstrosity all await, along with a mind-bending force - Great Cthulhu! The characters have a chance to face an avatar of Great Cthulhu in the dwarven depths in the final confrontation of the adventure to free Mount Throndor and rid Faerun of a Far Realm invasion! An Adventure of Exploration Mount Throndor is a big, sprawling complex, a dwarven city with two major strongholds, a bridge system spanning a massive underground lake, and a deep mining complex. The scale is difficult to grasp and convey. Previous examples of adventures featuring these elements have included maps - usually lots of them, great spawling maps connected at ends to make huge subterranean dungeons. It is the classic image of a D&D dungeon crawl, and the map is a key component to its visualization. However, in this adventure, the maps are handled differently. There are certain areas, ususally outside the dwarven city itself, that include maps that are suitable for use at the game table, either in theater of the mind style or grid-and-miniatures. Mount Throndor itself is presented with an abstract map, and exploring it utilizes the exploration procedure outlined in Appendix A. Characters traverse the huge subterranean system using this abstract system, and during their travels they are going to run into random encounters and sites with more interesting and complex encounters.

Part 2 of the "The Devil We Know" campaign arc. Cassomir's Locker is a Pathfinder Society Scenario designed for 1st to 7th level characters (Tiers: 1–2, 3–4, and 6–7). The Pathfinder Society dispatches you to the catacombs called Cassomir's Locker to find the source of a rat cult breeding monstrous vermin. After clearing Cassomir's dank sewers and delving into the dirty dungeons below, will you find the artifact that powers Cassomir's Locker or bring about the destruction of Taldor's most important port?