The oldest and most influential sci-fi TTRPG of all time meets the world’s most popular roleplaying game, with a complete 5e conversion by World’s Largest RPGs.

Through 2025, Nat19 has created quarterly splash books for 5th Edition, featuring new options for players and GMs—now we're funding physical copies in both soft and hardcover formats!

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!