Game systems
Play any campaign, on any Foundry system
Foundry lists more than 450 game systems, and the campaign you bought runs here whichever one it was written for. Familiar reads the world you imported and runs the story around your system's own rules. One part stays D&D 5e only, and this page draws that line exactly, before you pay for anything.
Two answers, and yours is one of them
"Does it work with my system" has two answers, and both are real.
D&D 5e (2024)
Everything, including the rules engine. Familiar checks each action against the 2024 rules and refuses the ones that break them.
Every other Foundry system
Everything except the rules engine, which means four jobs: refereeing combat, resolving spells, levelling a character up, and rolling initiative. Familiar still names your system in its first reply, looks rules up in your own compendium and journals instead of quoting D&D at you, and reads your characters the way your system stores them. A native read of your system's own sheet fields is on the roadmap, Pathfinder 2e first; until then they come through untranslated.
Where the line falls
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.
| What you are asking for | D&D 5e (2024) | Every other Foundry system |
|---|---|---|
| Story, NPCs, scenes, lighting, weather, audio, voices, images, transcription, journals, campaign memory, your own compendia | Yes | Yes |
| Reading your characters | Abilities, hit points, AC, saves, spell slots, and inventory, plus who the character is: alignment, size, class levels, and the pronouns their sheet carries rather than a guess. Ask and it reads the biography, skills, languages, and resistances too, or the party sheet's roster with levels, HP and AC. | Your system's own sheet, passed through untranslated, with hit points where the sheet keeps a pool Familiar recognises |
| Refereeing combat | Every action checked against the 2024 rules | No. Your system resolves it, the way it already does |
Verified on real Pathfinder 2e, Dragonbane and Troika worlds, the first two on Foundry v14.
Systems with their own page
- Pathfinder 2eThe encounter budget is done and the road it happens on is still four empty squares. Familiar sets that road, imports the creatures for it out of your own compendium, and voices whatever the party stops to talk to.
- LANCERMech combat is the part of this game that already looks after itself. Familiar sits with the campaign those missions belong to: the briefing room, the downtime, and the people who keep turning up in both.
- Pathfinder 1eSix volumes of an Adventure Path, with the sheet arithmetic already handled by the pf1 system. What Familiar takes is the part that was only ever in your head: the voices, the scenes, and the rulings you have to keep.
- Warhammer Fantasy 4eThe ninth coaching inn of a long Empire campaign still has to smell of something. Familiar dresses it, fills it with tired and badly paid people, and has them sound the same the next time the party stops there.
- Call of Cthulhu 7eA published Call of Cthulhu campaign ships dozens of clue handouts, and the one the table needs now is never the one you have open. Ask for it and the page comes back in your own wording, with a voice for whoever is meant to be handing it over.
- Cyberpunk REDGigs come in, the crew burns bridges, and next week there is another one. The cyberpunk-red-core system keeps the dice and the armour; Familiar keeps the district, the voices, and who owes whom.
- DaggerheartDaggerheart has no turn order, so a GM here is talking almost without a break and nothing the table invents mid-scene gets written down. Familiar does the writing while you keep talking.
- Savage WorldsOne set of rules and a shelf of worlds to run them in. SWADE keeps the trait dice, the action deck and the wound maths; Familiar takes the world they happen in.
- ShadowdarkThe shadowdark system counts the torch down in real minutes, and it does not stop while you look something up. Familiar is what you ask instead of leaving the table.
- DragonbaneOn Dragonbane the rules arrive as journal pages in your own world. Familiar reads those pages, voices what is written on them, and is honest about what is not.
Your system probably has a starter waiting
Familiar carries a Table Rules field per world, and it offers a starter template written for the table culture of the ten most-played Foundry systems. Yours is offered first when Familiar sees your world. Anything outside that ten gets the generic starter with your system's name already filled in.
It is not a ruleset. It sets the terms your table uses and leaves room for your setting, your tone, and your house rules.
Your system has no page of its own
Then the second answer above is yours, and it is a real answer rather than a hedge. Dragonbane is the worked version of it: no starter written for that system, nothing configured on the world, and every claim on its page above checked against a run on a real one. Read that page and you are reading what the second answer gets you.
A page here has to earn itself: a system gets one when there is something true about it that is not already true of one listed above. If you play something not listed and want it covered, the Discord is the fastest route to me.
- TroikaVerified live on a real Troika world at Familiar v2.25.0, with no starter of its own. Familiar's two NPC sheet buttons reach its older-style actor sheets too.
Fourteen days free, and no key needed if you already pay for Claude, ChatGPT, Gemini, or SuperGrok. Try it on the campaign you already own.