Back in the 1970s, a new role-playing game built a foundation that would stand for years to come, a foundation of accessibility, hackability, and ease of use. Am I talking about D&D? Absolutely not! I’m talking about RuneQuest, a game which, in 1978, not only became a quick second place finisher to D&D in the fantasy genre but also established many RPG conventions we still see today. In 1980, the RuneQuest second edition box included a little 16-page booklet titled Basic Role-Playing, and from there it was off to the races. Basic Role-Playing (later Basic Roleplaying, also called BRP) would form the basis of every game released by RuneQuest’s publisher, Chaosium. As that esteemed publication history includes none other than Call of Cthulhu, BRP is likely the bestselling house system in the history of role-playing games.

Thanks to RuneQuest and Call of Cthulhu, BRP forms the cornerstone of how gamers expect d100 systems to work. In short, your attributes and skills give you percentile values which are equal to the probability of rolling under them on a d100 roll. Look at your sheet, you know how likely you are to succeed at a baseline roll. In addition to BRP itself, this mode of d100 mechanics saw widespread adoption in games as varied as Warhammer Fantasy Roleplay and Eclipse Phase. Now, Chaosium is staking the future of BRP on its utility as a platform. The new edition of Basic Roleplaying is here, and it’s being marketed to game designers as much if not more than game masters.