I open-sourced Nat20, the rules engine behind the game I am building.

It is a host-agnostic Python library for D&D 5e SRD 5.2. Combat, skill checks, saves, effects, and grid or zone-graph movement run without a game host, network connection, or database. The engine code is MIT. The bundled SRD dataset is CC-BY-4.0.

I split it out because I did not want an LLM, a browser app, or a virtual-tabletop runtime deciding the rules. The model can narrate a goblin slipping in the rain. Nat20 should still answer the same way about cover, spell slots, and Sneak Attack.

The repo includes a small local demo and a clean-install smoke test. It implements much of SRD 5.2, not all of it, so there is a capability matrix in the docs before anyone depends on a specific mechanic.

Source: https://github.com/tapestria/nat20

I would like feedback from people who have built on open game rules: what makes a rules library actually useful outside the game that created it?

Roll or customize from 2+ billion combinations across 27 categories - each with a fresh stats, name, description, effects, abilities. If you play any fantasy TTRPG like AD&D, DnD 5e, Pathfinder 2e, you'll find inspiration. It's free. No ads. No accounts.
https://opendungeons.com/magic-item-generator

A weekly post to share rpg tables and tools used in RPG prep or games, with any examples that were surprising, useful or amusing.

I've been working on Mytharion, a tabletop RPG toolkit that I'm developing as a solo project.

The first major tool I'm releasing is Cartomancer, a web app for managing and organizing tabletop RPG campaigns and maps. You can keep track of locations, markers, points of interest, distances, and other campaign information in one place.

I'm also working on a VTT and additional tools for Game Masters and players.

The project is still in active development, so there may be bugs or unfinished features. Feedback, bug reports, and suggestions are very welcome and genuinely help shape the project.

I'm currently giving the first 50 users a 7-day trial with the code:

MYTH-P8N3-5TY2-52WP

Valid until September 28, 2026.

Try it here:
https://mytharion.app/redeem

I'd especially like to hear what RPG tools you currently use and what you feel is missing.

Recently came across Roll Ruin, a generator which creates one dungeon room at a time. It includes a description, room map and other details.

There's also a list of other tables to integrate into the room, such as door trap, treasure, npc and secret. There are filters for biome, room/passage/entrance and tier (although click on a filter removes it from the selection!)

It's based on tables created by Natural Peocock, the Roll 4 Ruin: Classic Dungeon Generator.

I've created a hex-fill procedure for my Sword & Sorcery setting (South-East Asia during the last Ice-Age). My blog post includes an example area of 19 hexes.

The procedure consist of tables for generating geographic features for different biomes as well as prompts for dangers,, natural hazards, ruins and settlements. The 7 tables for generating the 'Unusual / Weird / Sorcerous' are especially fun for creating the S&S aesthetic.

For example here are 7 results from those tables: 18: Tainted 1: Pyre 8: Talisman 4: Summon 8: Glimmer 9: Lurching 16: Crepuscular

The focus for this procedure is on the geographic information but I have many other tables/generators for cultures, cities, factions etc. on my blog. All with the same S&S theme.

Sword & Sorcery Hex-Fill Procedure

Edit: I’ve been experimenting with using AI tools to generate the dice rolls and present all the results for me. I’m not sure how random the results are? Google has an in built dice roller so I wonder if Gemini or NotebookLM has access to that. Anyone have experience with this? It saves having to roll and collect all the results manually.

I've been making random name generators on and off for quite a few years, and I've recently started building a new collection aimed more specifically at tabletop gaming and RPGs.

I've got three live at the moment:

• Warband Name Generator
• Gang Name Generator
• Faction Name Generator

They're all free, browser-based and system-neutral. Although they're hosted on the Thrackdown site, they're deliberately not tied to the game itself.

I've been thinking of them more as tools for things like naming rival factions, enemy groups, mercenary companies, cults, gangs, NPC-controlled warbands or anything else you need to come up with quickly during campaign prep.

I'm planning to keep expanding the collection, so I'd be interested in any feedback on the current generators, particularly where the results feel repetitive or where additional themes/categories would be useful.

HewnHero.app is a free D&D 5e and 5.5e Character builder that uses a GitHub-hosted, JSON-based, SRD-only (5.1 and 5.2) database that you can clone and add your own material.

Check it out if you will. It's still in the works so shout out if you find any bugs, won't you?

Hello — I’m Elias Oakhaven, curator of The Oakhaven Archive. I create compact, system-neutral narrative tables (CSV + PDF) meant to drop straight into GM prep or a dev content pipeline.

Free sample (10-item inventory — CSV-ready)

• LOCKET — Unknowable Locket — A silver locket with no hinge; fused shut. Smells of rain. — Weight: 0
• CUP — Historian’s Tea Cup — A bone-white cup with a jagged, story-filled chip. — Weight: 0.5
• MIRROR — Cruel Looking-Glass — A mirror in blackened oak that shows the user's happiest day. — Weight: 4
• BOOK — The Author’s Debt — A manuscript that ends mid-sentence. Pages hum with energy. — Weight: 1
• POTION — Cellar Tincture — A thick liquid that tastes like silence; causes hallucinations. — Weight: 0.2
• BELL — The Silent Bell — A handbell with no clapper. It rings only in the user's mind. — Weight: 0.8
• LEDGER — Moth-Eaten Ledger — A business book where the numbers shift when unobserved. — Weight: 2
• KEY — The Key to Nowhere — A heavy iron key that fits no lock in the known world. — Weight: 0.3
• MAP — The Faded Map — A detailed map of a vast city that was never actually built. — Weight: 0.1
• THIMBLE — Widow’s Thimble — Protects from needles, but not from the sting of memory. — Weight: 0

Why this is useful

• Clean CSV schema (ID, Category, Item_Name, Description_Text, Weight) for import into spreadsheets, engines, or table tools.
• Short, evocative descriptions that function as hooks rather than exhaustive lore.
• Easy to filter, sort, or expand with extra columns (Hook, Plot_Tag, Mechanic).

Questions for the sub

• Which file format do you actually use most for prep or imports? (CSV, JSON, Google Sheet, or card images?)
• Would you prefer an extra column for a single-line mechanical hint or a short plot tag?
• Are there any naming, column, or formatting conventions you find essential for engine ingestion?

If you want the actual CSV file or a pasted CSV block, say which format you prefer and I’ll drop it in a comment. I’ll follow subreddit rules on linking or self-promo — this post is primarily to share a practical sample and gather format feedback. If you're curious, you can take a look in Itch.io

— Elias / The Oakhaven Archive

A weekly post to share rpg tables and tools used in RPG prep or games, with any examples that were surprising, useful or amusing.

Bonjour, je suis en cours de réalisation d'un site pour générer des fichiers de personnages (format PDF à la sortie). Alors forcément je propose en premier les jeux pour lesquels j'ai les livres. Certains pourraient-ils tester et de me faire des remontées ? Améliorations, bugs, offrandes aux fisc à ma place etc ^^

Voici la liste des jeux FR :

- Appel de Cthulhu V7

- Bloodlust (pas la métal)

- Donjons & Chatons

- Fading suns V1

- Mage l'ascension

- Star Marx

- Star Wars (D6)

- Star Wars : Force et Destinée

- Warhammer V1 (en cours)

C'est un site amateur je rappelle : https://decados.fr/

Merci pour vos retours constructifs !

I'm a solo dev and I've been building this for a while: a pocket toolkit for running tabletop games with no GM, or for prepping one if you are the GM.

The core is an oracle. Ask a yes or no question at any odds and get an answer back, sometimes with an "and" or "but" twist, while a Chaos factor decides how wild things are and how often random events crash your scene. It tracks your open plot threads and your NPCs, and events target them by name, so the story builds on itself instead of drifting. There are two other oracles too: a tarot engine, and one where you bind a cursed artifact and play out the tug of war for control.

Behind that sit 43 generators: NPCs, quest hooks, rumors, encounters, mysteries, magic items, an original-creature bestiary, dungeons, maps (continents, hex crawls, towns, treasure maps, sci-fi star charts), factions, realms, faiths, and a world engine that simulates several kingdoms into one shared history. Anything you roll can be saved, sorted into folders, pinned to a campaign board or a timeline, and exported as PDF, text, Markdown or an image.

Free, works fully offline, no account, no ads, and no AI anywhere in it. Every result comes from handwritten tables and procedural rules running on your phone.

https://play.google.com/store/apps/details?id=com.avaton.fantasynamegenerator

Happy to hear what's missing. Most of the last few releases came straight from user suggestions.