Old-School Essentials
Old-School Essentials is classic B/X Dungeons & Dragons, rebuilt for the table: the same beloved 1981 rules, laid out so cleanly you can actually *find the thing you need* mid-game. It's the OSR community's go-to for elegant, no-friction old-school play — every procedure on its own tidy page.
Two lines share one core: OSE Classic Fantasy (pure B/X) and OSE Advanced Fantasy (which adds AD&D-style classes, races, and spells).
Where to get it
The rules are open; the presentation is the product:
- OSE SRD — the full ruleset, free online, to learn, reference, and build on.
- Necrotic Gnome — the gorgeous print + PDF books (also on DriveThruRPG and OSR retailers). The layout is the reason to buy.
The SRD is free and open. OSE publishes its rules as an open SRD you can reference and build tools on — like this one. The beautifully typeset books are the paid product; the rules themselves are open.
Classic or Advanced?
- Classic Fantasy — the pure B/X experience: four core classes, race-as-class, fast and clean.
- Advanced Fantasy — modular add-ons for separate races and classes, more spells, more options; bolt on as much or as little as you like.
Both run on the same engine, so you can start Classic and grow into Advanced.
Roll some tables
OSE runs on its tables — encounters, treasure, dungeon dressing. Roll on OSE's tables (and hundreds more) for free, no account needed, at the RPGsecrets tables app.
Build a character
We support OSE Classic and Advanced — roll abilities, pick a class (or a race and a class), buy gear, and keep a sheet that handles the bookkeeping, ready for play.