Sorcerer is a tabletop roleplaying game by Ron Edwards. It is an explicit precursor to Apocalypse World, being mentioned in those rules several times (and by extension, all of the Powered by the Apocalypse games).

This is a version of the rules fully annotated by the Edwards 10-15 years after the initial publication of the game. It’s super interesting and a real source of thoughts about how Sorcerer should be GMed/played but also how roleplaying should be done generally. Especially for people like me, who are interested in the collaborative storytelling potential of tabletop roleplaying games (that’s what they excel at IMO).