Principia Apocrypha: Principles of Old School RPGs, or, A New OSR Primer

Principia Apocrypha is a new, free Primer for OSR and other Old School Style RPG Gaming in the form of a collection of Apocalypse World-style GM (and player) Principles with text from Ben MiltonSteven Lumpkin, and David Perry (myself).

Principia Apocrypha, a New OSR Primer

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If you'd like to leave comments or suggestions about Principia Apocrypha, you can do so here!

A note on translations: PA is provided under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. Accordingly, you are free to translate it into any language and to provide it in any form for free. I'd be happy to include links to translations on this page; make a comment here and I will add it.

Further Reading & Recommendations


My curated selections for next steps if Principia Apocrypha is your introduction to the Old School Style Play, as of September 2018.

Other Old School Primers


Examples, Examinations, & Extollations of Old School Style Play


In increasing order of time investment:
  • Why I Like OSR – Emmy Allen explains what she values from this style of play and the culture surrounding it.
  • On Romantic Fantasy and OSR D&D – Joseph Manola on how old school D&D favors communication over violence as a default to problem solving.
  • Thursdays in Thracia – Series of session reports and thoughts on running B/X D&D from a GM new to old school play.

Some Games/Rulesets For Your Consideration


Retroclones & Refinements of B/X D&D


B/X is arguably but widely revered as the edition of the Original Fantasy Roleplaying Game best suited for old school play. It consists of two books originally published in 1981: Tom Moldvay's Basic D&D and Dave Cook's Expert D&D. Other editions and flavors of D&D are available. 
  • Old School Essentials (Free text-only version) from Gavin Norman – Hewing very closely to the original rules, OSE combines and reorganizes B/X into more easily usable chunks, clarifies  ambiguities, and builds in the option for the simpler Ascending style Armor Class.
  • Labyrinth Lord (Free no-art version) – The first and still perfectly respectable retroclone of B/X.
  • Lamentations of the Flame Princess – Features some simplifications and alternate mechanics, widely considered great improvements on B/X, also oriented to more gritty, low-fantasy setting assumptions. [I no longer support LotFP as a publisher, so this link goes to the free version of the rules]
  • Quintessential BX – Built on OSE's Core Rules, with some tweaks from myself and taken from LotFP, and some favorite common house rules.
  • 5E D&D – It isn't the worst edition for old school play, certainly the best since 2E, and many versions of "O5R" hacks can be found, but I have not dug into them. Here's a start.


Newer, Lightweight Rulesets


Many folks consider OD&D and B/X to already be rules-light (usually compared to 1st/2nd edition Advanced D&D), but over the years, many rulesets have popped up that pare it down even further to emphasize core old school principles. Here are a few I recommend for newcomers:
  • The Black Hack (Free web version) from David Black – A popular modernized version of OD&D. An expanded second edition is in the works.
  • Into the Odd (Free edition) from Chris McDowall – Tight rules for delving in steampunky dungeons. Three attributes, no to-hit rolls; in combat everyone just deals their damage. That will teach you to charge in headlong.
  • Maze Rats from Ben Milton – Simple and quick, takes many cues from Into the Odd. The source of much of Principia Apocrypha, and host to an incredible collection of random tables. Roll on'em er'y day.
  • Knave from Ben Milton – Hot off the presses as of this writing, a cutting-edge, feather-light, but highly old-school compatible ruleset. Might be my next choice for running a game.

More Narrative-Style Rulesets


These are less concretely Old School, but evoke and/or permit aspects of it in their design and play. Beware of folks telling you that these rulesets are antithetical to old school style play – you have permission from both me and their designers to do whatever you want with them. All are Powered by the Apocalypse-ish. Presented in order of increasing rules-weight:
  • World of Dungeons (free) from John Harper – Very lightweight version of Dungeon World. No guidance on running, so plan on assimilating both DW and Principia Apocrypha.
  • Dungeon Rats – My mostly-finished hybrid of Maze Rats and World of Dungeons aiming for greater compatibility with old school material. Ditto above.
  • Vagabonds of Dyfed from Ben Dutter – Designed with the goals of combining PbtA and old school sensibilities, and compatibility with old school material.
  • Freebooters on the Frontier from Jason Lutes – A hack of Dungeon World for a more old school feel; a second edition is the works.

Outstanding Introductory Old School Adventures


Modern & Recent


Timeless Classics

  • The Keep on the Borderlands – Boxed with Basic D&D, many old school gamers cut their teeth on this open, sandbox-style dungeon of competing factions.
  • Caverns of Thracia – Exemplar of megadungeons, designed by Jennell Jaquays.