Let's get this going.

What's your favorite OSR?

Ones I have, * means played.

OD&D * AD&D * Basic Fantasy * Castles & Crusaders Old School Essentials (OSE) Hyperboria OSRIC Advanced Labyrinth Lord Swords & Wizardry * Pathfinder 2e Dungeon Crawl Classic Tunnels & Trolls

My go to is AD&D...