Game RPG BRP:Main Page
The Basic Roleplaying System is the flagship system of Chaosium Inc., one of the oldest role-playing game companies still in operation. It had its germ as the system behind the fantasy roleplaying game RuneQuest, published in 1978, and was first spun off into its own generic system in 1980, when a BRP standalone booklet was included in the boxed set of RuneQuest's second edition. Most (though not all) of Chaosium's games since have run on some variant of the Basic Roleplaying System, including Call of Cthulhu, Pendragon, StormBringer, and most recently Rivers of London.
In 2020 Chaosium announced that the system would be released under an open license. While its initial attempt at an open license was, while no doubt well intentioned, very poorly implemented, in 2023 a new version of the Basic Roleplaying Game was released under a genuinely open license (namely the ORC). The intellectual property associated with the various Chaosium games based on the system is not of course covered by the license, though Chaosium does participate in two community content programs—The Jonstown Compendium and the Miskatonic Repository—that allow people to publish their own material for RuneQuest and Call of Cthulhu, respectively, subject to certain conditions and restrictions.
Basic Roleplaying and the various derivative systems it spawned are often collectively called "d100 systems", because the core resolution system involves rolling a number from 1 to 100 on "percentile dice" and comparing the result to some skill, attribute, or other value, or some multiple or fraction thereof. Other types of dice may, however, be used to determine damage and for some other purposes. If you want to give Basic Roleplaying a try without spending money on it before you know if you like it, there's plenty of free material on the Chaosium site including adventures and "QuickStarts" for both RuneQuest and Call of Cthulhu.
You can use BRP statistics for Wongery materials if you'd like to incorporate Wongery creatures and other content into a Call of Cthulhu or RuneQuest game—or, of course, if you're just a fan of the Basic Roleplaying System and want to use the system for a campaign set on some Wongery world. It shouldn't be too hard to adapt them to other BRP-inspired, d100-based systems such as Mythras, OpenQuest, and Legend, though the Wongery may later add Game pages specifically for some of those systems.
Note that the statistics here include some characteristics, such as hit locations and SAN scores, which pertain to optional subsystems of the BRP rules. This doesn't, of course, mean that you have to use these systems if you're using this material; we just thought it was better to include this optional information, so those who don't need it can simply ignore it, than to omit it, and require those who do need it to work it out themselves.
With the exception of this initial page, all pages in the Game:RPG:BRP subspace are published under the Open RPG Creative License, links to which are included at the bottom of each applicable page.