Apocalypse World definitely hit me hard in terms of how it specifically structure the GM side of the game. Up until then, game texts were lots of rules and then some wishy washy advice about telling stories. AW said “nah, man, you do this shit and only this shit, and you do it like this”.

Microscope similarly showed me that players can be trusted to make up cool shit – something over a decade of GMing made me terrified of. Players ruin MY STORY, right?