Letter + A4 PDFs, plus markdown sources
GM Codex — System-Neutral Random Tables & Prep Worksheets
40 random tables and 10 printable worksheets for game masters — no stat blocks, no conversion, works with any tabletop RPG.
Look inside
Real pages and screens from the files you download.
About
GM Codex is a working tool, not a lore book. Forty random tables and ten printable worksheets, all system-neutral, so nothing needs converting to whatever game your table plays.
Every table is d20 or d12, and every entry is a full sentence with a hook already inside it — a name and the debt attached to it, a rumour and the person who benefits from it being believed, weather that forces a choice. No one-word results you still have to invent around. Roll one line and a stalled scene moves.
Inside: four invented cultures with 20 names each, plus NPC wants, secrets, quirks and trades. Tavern and road rumours, jobs with a catch, overheard fragments. Mid-scene complications, twists, fight complications. Weather, hard weather, overland events, landmarks. Settlement features, problems, locals. Room dressing, doors, sounds and smells, traces of former occupants. Mundane curios, minor wonders, hoard flavour, gifts that cost something. Faction goals, methods, assets, weaknesses. Rewards that aren't coin, consequences of losing and of winning. Downtime events and entanglements.
Ten worksheets to print and write on: session prep, NPC card, faction tracker, encounter builder, travel log, settlement sheet, mystery and clue web, campaign arc planner, player-hooks tracker, session debrief.
Letter and A4 PDFs, an offline HTML roller (every table, plus quick NPC, settlement, site, faction, journey and job generators; open it in any browser, no install), and the markdown sources so you can paste tables straight into your notes app.
What's inside
- 40 tables (d20 / d12), 712 entries, every one a usable sentence — not a word list
- 4 invented cultures with 20 names each, and NPC wants, secrets, quirks, trades
- Rumours, jobs with a catch, mid-scene complications, twists, fight complications
- Travel, weather, settlements, site dressing, treasure, factions, consequences, downtime
- 10 print-and-write worksheets: prep, NPC card, faction clock, arc planner, debrief
- Letter + A4 PDFs, page numbers and contents, plus markdown sources for your notes app
- GM-Codex-Roller.html: an offline roller for every table with six quick generators and a roll log — one file, any browser, nothing sent anywhere
FAQ
Which system is it for? Any. There are no numbers, no stat blocks and no page references — only prompts you read in your own words.
Do I need a d20? No. Roll bigger and reroll high results, or just pick the entry that makes the most trouble. Picking is not cheating.
Can I use it in a stream or a paid game I run? Yes, including monetised streams and recordings. You just can't resell or redistribute the files.
Can I paste the tables into Obsidian or Notion? Yes — the zip includes all 50 markdown source files.
Is it printer-friendly? Yes. Black text on white, no full-page art, no coloured backgrounds to drink your ink. Letter and A4 both included.
AI disclosure
All content is original and system-neutral. The text was produced with substantial AI assistance and checked for originality, tone and usability at the table; no third-party game text, item names, creature names or trademarks are used.
Licence
Personal use. Print it, write on it, use it in your home games and in games you stream or record, including monetised ones. Do not resell or redistribute the files.