Game Changer

The forge of fantasy role playing, Gary Gygax's legendary dungeon and its environs. Here begins the journey into depths never before reached.

The World's Largest Dungeon is a 1,600+ page, four-book behemoth megadungeon. Experience the Guinness World Record-winning dungeon crawl like never before - fully updated to 5E of the Worlds Most Popular Roleplaying Game!

A mega-dungeon that supports a full-year campaign. A legendary adventure considered by many to be one of the greatest of all time! Explore a thousand-year-old dungeon mystery waiting to be solved...

Whether you’re a group of local heroes sent to investigate mysterious goings-on in the nearby haunted wood, or famous mercenaries plotting and scheming in the big city, the MCDM RPG makes building adventures and fighting monsters fun.