Solo FRPEvery solo game reaches the same moment: your hero puts a hand on a door, and you realise you do not know what is behind it, and that only you could say. A solo RPG oracle answers that moment for you. You ask a yes-or-no question, say how likely the answer seems, roll, and accept what comes. This guide explains how a yes/no oracle works, how to choose its odds, how to read answers that arrive with a twist, what the chaos factor from 1 to 9 does, and why some scenes refuse to go as planned.
What a solo RPG oracle does when there is no Game Master
What is an oracle in a solo RPG?
An oracle is a table or a rule that answers questions by chance. It stands in for what a Game Master has and you lack: knowledge of the world not shaped by what you want. It keeps you honest, since you cannot unbar a door because it suits you, and it surprises you, which is the reason to play at all.
Oracles come in two kinds. A yes/no oracle answers closed questions: is the door barred, is the innkeeper lying. An open oracle gives you words to interpret, such as an action and a subject, for questions yes and no cannot answer. Many solo roleplaying oracles pair the two; this guide is about the first.
An oracle does not decide whether your hero succeeds: “Do I pick the lock?” is a job for an ability check against a DC. The oracle tells you what is true about the world; the check tells you what your hero manages.
Asking a question the oracle can answer
How do you use a yes/no oracle?
- Ask a closed question. “Is the crypt door barred?”, not “What is on the crypt door?”
- Set the odds from what the story has already established.
- Roll.
- Read the answer in the light of the scene, taking the first sensible meaning.
- Write it down. It is now true, and later questions build on it.
A few habits make the answers better. Ask questions whose two answers would both be interesting. Phrase them so that yes means something happens (“Is someone following me?”, not “Am I alone?”), which keeps the chaos factor, below, pointing the right way. Do not ask the same question twice unless the situation has changed, and do not ask what you already know.
Setting the odds before you roll
How do you choose the likelihood of an answer?
Judge from the facts in the story, not from what you hope: what would a fair Game Master think, given everything established so far? An inn at night likely has a fire in the hearth; a crypt sealed for centuries is unlikely to have a living guard. When nothing points either way, call it 50/50. Set the odds before you picture the answer, never after.
If you want an oracle to use tonight, here is a simple d100 scheme. Roll two ten-sided dice, one for tens and one for units, and an answer at or under the chance is a yes.
| Likelihood | Chance of yes |
|---|---|
| Very unlikely | 10% |
| Unlikely | 25% |
| 50/50 | 50% |
| Likely | 75% |
| Very likely | 90% |
If you have only six-sided dice, roll one: 1 is no, and; 2 is no; 3 is no, but; 4 is yes, but; 5 is yes; 6 is yes, and. For a likely answer roll two dice and keep the higher, and for an unlikely one keep the lower.
Reading the answer: yes, and; no, but
A bare yes or no is often enough, but many oracles give more, and the shades are worth learning even if yours does not:
- Yes, and: yes, and more besides. The door is barred from the inside, and something is breathing behind it.
- Yes, but: yes, at a cost. It is barred, but the bar is old wood; force it and it gives, loudly.
- No, but: no, with a consolation. It is not barred, but the hinges will scream when it opens.
- No, and: no, and worse. The bar lies snapped on the flagstones. Whatever was kept in has already left.
Some oracles mark rare answers as exceptional. In Solo FRP’s Mythic-style oracle, which rolls a hundred-sided die against the odds, a roll of doubles at or under the chaos factor (11, 22, 33 and so on) turns the answer exceptional: Yes, and… or No, and…. Here is one, at the foot of the crypt stairs in The Whispering Crypt of Valdrath:
Scene. The bottom of the stairs below the abbey of Valdrath. The lantern’s flame flickers green, then gold.
You ask: Is the crypt door barred? Nothing you know points either way, so you call it 50/50. The chaos factor stands at 5.
The roll: 33. At or under 50, so yes; and doubles at or under the chaos factor, so the answer is exceptional. Yes, and…
You read it: Barred, from the inside. And the bar is new wood, still pale. Someone down there has been busy, and does not want company.
When an answer puzzles you, take the first reading that fits the scene. If it still makes no sense, ask a follow-up question rather than overruling the first.
The chaos factor, from 1 to 9
What is the chaos factor in a solo RPG?
The chaos factor is a number from 1 to 9 that measures how far the story has slipped out of the hero’s hands. Low, from 1 to 3, the world is calm and you shape it. In the middle, from 4 to 6, things go awry. High, from 7 to 9, the unexpected looms. In oracles built on the idea, the chaos factor shifts the odds: the higher it climbs, the more often fate says yes to the things you fear, and the more often surprises break in.
To add a chaos factor to the d100 scheme above, start at 5, and move the chance of a yes up by five points for every step above 5 and down by five for every step below it, never past 5% or 95%. At chaos 7, a likely answer comes up yes 85 times in a hundred.
When should the chaos factor go up or down?
At the end of each scene, look back. If the hero was in control, with plans that worked and their pick of where to go next, lower the chaos factor by one. If events drove the hero, through ambushes, failed plans or a scene that got away, raise it by one. Keep it between 1 and 9, and note it in your log for the next session.
Scenes that do not go as planned
What is a scene interrupt?
A new scene usually begins with one in mind: “I go to the abbey and search Father Cern’s room.” A scene check tests whether it goes that way. The Mythic Game Master Emulator checks each expected scene against the chaos factor, and a low enough roll either alters it, a twist on what you expected, or interrupts it, so something else happens entirely. A simple home rule works too: roll a d10 as each scene opens, and on a 1 or a 2 the scene is interrupted.
Say you set out across the square for the abbey, and the pale boy is standing in the rain ahead of you, one finger raised to his lips. Treat the interruption as the new scene, play it through, and return to your plan afterwards if it still makes sense. Interrupted scenes are where a solo story stops feeling like your outline and starts feeling like a world.
An oracle beside an AI Game Master
Can you use an oracle with an AI game master?
Yes, and they pair well. The AI narrates and plays the world; the oracle settles the questions you want settled by chance rather than by a narrator. Any narrator, human or AI, leans toward drama, a tidy plot or pleasing you. An oracle leans nowhere. Use it for questions you would rather not leave to the narrator, such as “Has anyone followed me from the vale?”, above all those a narrator might answer yes because yes is exciting.
With a general chatbot, roll the oracle yourself and give the answer to the AI as an established fact. Solo FRP keeps its oracle on the play screen: ask a yes-or-no question, choose how likely the answer seems, and it answers against the chaos factor, with every answer shown, odds and all. Scenes there can be interrupted too, and the tale turns somewhere new. The AI Game Master guide covers the rest of what to look for.
If you want a solo RPG oracle online to try right now, the Oracle chapter on the first page of this site is a working one: type a question, choose the odds, set the chaos factor and roll.
Where the idea comes from: Mythic and other oracles
What is the Mythic GM Emulator?
The Mythic Game Master Emulator, by Tana Pigeon and published by Word Mill Games, is a long-standing GM emulator for playing any roleplaying game without a Game Master, now in its second edition. Its Fate Chart crosses the odds of a question with the chaos factor to give a chance of yes; its chaos factor changes the tempo of an adventure as you play; its scenes are checked against that factor and can be altered or interrupted; and random events and lists of open threads and characters keep the story moving. Two of its ideas, the chaos factor and the altered or interrupted scene, are now common words among solo players.
Other oracles take simpler paths: the d6 ladder above, oracles printed inside solo games, word tables that pair an action with a theme. They all do the same work. Solo FRP’s oracle is Mythic-style, after the Mythic Game Master Emulator, and like every oracle it answers only what you ask.
For where the oracle fits in a whole session, read how to play a solo RPG, and for questions asked on the road, the solo hexcrawl guide. The oracle and the chaos factor are also on the How it works page.