In Shadowdark the torch burns while you look things up.

What the shadowdark system is already counting

The light first, because it is the reason this system feels different from everything else on Foundry. A tracker in your world ticks the world clock forward one second per real second and takes that time off every burning light. When one runs out it says so in chat by name, switches the token light off and removes the item. There is a GM window listing who has how long left, open by default, with a button to douse any of them. A torch dropped on the floor keeps burning as an actor of its own and can be picked back up.

The rest of the counting is quieter and just as settled. Gear slots are added up from what a character carries and go red when the total passes what they can hold. A failed casting marks the spell lost without being asked, and a scroll goes away entirely. Luck is tracked and spent from the sheet. Ammunition comes off on a hit. Armour class comes off the equipped armour. There is a character generator, an importer for characters built on Shadowdarklings, statblock importers for monsters and spells, and a starter dungeon packed in with the system.

None of that leaves much arithmetic to want help with, which is why this page is not about arithmetic. What is left is everything the game asks you to have at hand while a clock is running: what your own notes say, what somebody was promised, who this creature is now that the reaction roll went the wrong way, and what any of it was called.

And it comes out of your world or it does not come out at all. The compendium packs installed there, the dungeon key you wrote, last session notes. The starter dungeon that arrives with the system counts too, which is a better standing start than most new Foundry worlds get.

• The name of somebody the party met two sessions ago, off your own page, before anyone starts guessing
• A monster out of your own compendium, brought up while the party is still deciding whether to open the door
• A voice for the thing that turned out to want to talk, with one want it holds for the whole conversation
• Scene darkness set where you say, and a torch-coloured light placed where you want one
• The session note written down while the session is still going, onto a page you can open next week

• What has to be in the world before you askNothing gets read back that nobody laid in there first.

What a fast game still leaves you holding

Shadowdark GMs say in print that this is an easy game to run, and they are right. The book took out the things that slow a table down, and the system took out most of what was left. So this is not a list of burdens anybody built for you.

It is a list of two shapes. Things that cost seconds you are paying for in light, and things that only exist between sessions, where this game has a problem most do not: characters die here, and what they were carrying for the campaign dies with them.

• A quest the party took on from someone who is now three characters ago, and nobody left holding the thread
• What a faction was actually promised, and by whom, in a session two of the current players were not at
• The dungeon key you wrote yourself, and the half minute it takes to find the right room on it
• A wandering monster that comes up wanting to bargain instead of fight, needing a name and a want immediately
• The write-up that would make next week easier, which does not get made, because making it means stopping the game

One ask, with the torch already well down

The party has doubled back to a room they cleared last session and nobody can agree what was in it. So the question goes in the way it would be said out loud, while they argue. "What did they leave in the shrine, and who did they promise it to?"

The answer comes off pages in your world and from nowhere else: the key you wrote for that level, the notes from the night it happened, whatever anyone put down about the priest. Where a thing was never written, the reply says that instead of inventing something, which is what the starter below asks for in as many words.

The priest is two rooms away and, going by what is written about him, would rather bargain over it than fight about it. So the next line is a voice. He turns up wanting one thing, he does not drift off it while the conversation runs, and the thing he wants was on your page before anybody asked.

What gets said back goes onto the same key while the scene is still running, so it is a little more complete than it was five minutes ago.

All the way through, the light is doing exactly what it was doing before, on your system's clock and not on anybody else's. The order in the tracker has not moved either.

The starter tells it to be dangerous, and that is the unusual instruction

An assistant arrives soft. Left alone it will warn twice, pull a punch, offer an exit, and generally behave as though the point is for everyone to be all right. At this table that is not a small mismatch in tone, it is the wrong game, and the starter Familiar offers a Shadowdark world says so directly rather than hoping it gets picked up from context.

Read what it actually asks for. Play traps and monsters as truly lethal, but telegraph the danger so a careful party can avoid it. Not every creature wants a fight: let them flee or bargain, and let players sneak or talk past. Reward how the players describe searching and solving problems. Those are instructions about how to be a danger fairly, and none of them is the sort of thing that comes as standard.

It also opens by naming the vocabulary your table uses, which matters here for a reason that is easy to miss: nobody in this game sees in the dark. Not one ancestry in the system carries it. So darkness is not a lighting note in this game, it is the thing the party is spending resources against, and terms like the light timer, gear slots and Luck are all names for the same pressure.

What none of that touches is the call itself. Where something is genuinely in doubt, the starter sends the question back to you and the lookups go to the compendium and journals in your own world.

One line in there does more work than the rest, and it is the one about rolling only when the outcome is actually in doubt. Without it a model reaches for a check on every sentence, which is the fastest way to turn a crawl into a queue of dice.

Where the rules engine stops

On Shadowdark, Familiar runs everything around the rules, and the rules are the one thing it does not touch.

Refereeing the rules is D&D 5e (2024) only. In combat the tracker, the turns, and the tokens still work; the rulings stay yours.

One setting to change: turn the combat auto-pilot off in Familiar's settings. It drives NPC turns through the 5e engine, so it does not know your system; the monsters' turns stay yours to run. Playing solo, that is the part you will feel.

This table is read from Shadowdark's own data model and Familiar's shipped code. It has not yet been run at a live Shadowdark table, so nothing here is described as observed.

The starter your table begins from

Familiar carries a Table Rules field per world, under Settings, System Rules. Whatever you put there is appended to every request, and it reaches your MCP client too.

Shadowdark has its own starter, offered first when Familiar sees your world. It is a starting point rather than a ruleset: the terms, the table culture, and slots for your setting, your tone, and your house rules. Paste it, then cut what does not match your table.

We play Shadowdark RPG, old-school d20 play. Use Shadowdark terms: torch and light timers, gear slots, spellcasting checks with spells lost on a failure, Luck Tokens, Talents, and no default darkvision. Look rules, spells, and monsters up in this world's compendium and journals, and defer every rules call to the GM.
The system tracks gear slots, light timers, and checks itself, so let it.
Standing guidance:
- Keep the light timer running and let the dark close in. Warn the party when a torch is guttering.
- Play traps and monsters as truly lethal, but telegraph the danger so a careful party can avoid it.
- Not every creature wants a fight. Let monsters flee or bargain, and let players sneak or talk past.
- Reward how players describe searching and solving problems. Roll only when the outcome is in doubt.
- Recall names, maps, and treasure from the written notes, not memory, and admit what was never recorded.
Setting: [your world or the dungeon you are running].
Tone: [old-school and deadly: darkness matters, treasure over combat].
House rules:
- [rule]
Never speak or decide for the player characters.

Nothing here is watching the clock

Everything down to here is what a read of a Shadowdark sheet reaches. What follows is what it does not, beginning with the one that costs this game the most.

• There is no clock inside Familiar, and there is no version of this where there is one. It does something when you ask it to and nothing at all in between: it will not count down, will not interrupt you at the fifty-fifth minute, and does not find out that a light went out. Your system does all of that on its own. Read the first line of standing guidance in the starter below with this in mind, because it is easy to read the other way: it is about how the dark gets described once you have said where the light stands, not a hand on the timer.
• The pool does travel further here than it usually gets to, because your system happens to keep it exactly where the scene listings, the token listings and the GM screen already look. That makes the honest warning the opposite one. Every one of those is a reading taken at the moment you asked, and on a crawl the thing you want to know is what changed while nobody was looking. The bars on your own tokens are the live copy.
• A figure from outside never goes into that pool, and not because it would bounce. Your sheet keeps its pool in the shape Familiar knows, so one pushed in would land. It stays out because your system has its own way of taking a character to zero, and on a game where that happens as often as it does here, walking around that is the wrong kind of help.
• Foundry's own status markers flip from chat, and the reply says which ones actually stuck. Shadowdark's own conditions are a separate thing: Afraid, Blind, Cursed and the rest are items in the system's pack and carry no status id at all, so a toggle has nothing there to reach for. Putting one of those on is still something you do on the sheet itself.
• The refusal on initiative is cheap here and still a refusal. Your system has an order of its own and your tracker already knows how to get it, so what you lose is a step, not an answer.

Three things this game counts and Familiar keeps score of none of them: the light, the gear slots, and Luck. All three live in your system, all three are where a Shadowdark session is won or lost, and not one of them travels with a character.

This system already ships a way to play it by yourself

Shadowdark is one of the few systems on Foundry that comes with solo play in the box. The oracle and its rules are packed in with the system, and so is a starter dungeon, which means a brand new world already has something in it to crawl.

That oracle and Familiar are not the same offer, and the difference is worth being exact about. An oracle answers a question nobody at the table has decided yet: yes, no, yes but. Familiar runs the side of the table you would otherwise be running yourself, out of material that already exists, which is the whole reason it works on a dungeon somebody wrote and not on a blank page.

So they stack rather than compete. Keep the oracle for what the fiction has not settled. Hand the prepped rooms, the creatures in them and the people worth talking to across to the thing that can read your world.

• Running a published dungeon on your ownWhat has to be prepped, and which half of the evening stays yours.

The parts that are the same everywhere

Connecting an AI, choosing a model, and what it costs do not change with your game system.

• Everything Familiar can doThe full tool reference. Everything outside combat refereeing runs on your system too.
• Connect Claude, ChatGPT, or GeminiThe connection steps, identical on every game system.
• Choosing an AI modelWhich model, and how much thinking headroom a hard scene needs.
• AI voices for your NPCsTTS setup and voice pinning, the same on every game system.
• Campaign memoryThe record and the recall, unchanged by your game system.