The Chaosium was founded by visionary game designer Greg Stafford in 1975. For more than forty years, Chaosium has captivated gamers, readers and mythic adventurers worldwide. Its award-winning roleplaying games, board games and fiction have been acclaimed as some of the most engaging and innovative of all time. Our RPG lines use the d100 Basic Role Playing system (BRP). Once you’ve learned to play one of these games, you’ve learned to play the others.