D&D Oracle & GM Emulator: How to Run Solo Games Without a DM
An oracle is the single most useful tool in solo tabletop gaming. It is a dice-based system that answers questions about the world so you don’t have to — which means it can stand in for a Game Master. Learn to use one and you can run D&D 5e, or almost any other RPG, entirely on your own.
This guide covers what an oracle is, how to build the simplest one in about thirty seconds, the major GM emulators worth knowing (including Mythic GME), and how to generate encounters and NPCs without a DM. For the wider picture of playing 5e without a group, see our solo D&D guide. New to solo tabletop gaming altogether? Start with the solo RPG guide.
What Is an Oracle?
In a normal game, the Game Master decides what the world does. Is the guard suspicious? Is the door locked? Does the merchant know anything useful? The GM answers, and the game moves on.
Playing alone, you have a problem: if you answer those questions yourself, you already know the answer. There is no surprise, and without surprise there is no game — only daydreaming with dice nearby.
An oracle solves this. It is a randomizer that answers your questions for you. You ask, you roll, and the result tells you what is true. The world pushes back. You are genuinely finding out what happens rather than deciding it.
That is the whole idea. Everything else — chaos factors, scene generators, meaning tables — is elaboration on top of that one move.
The Simplest D&D Oracle (Build It in 30 Seconds)
You do not need to buy anything to start. Take a d6. Before any moment where the outcome is uncertain, phrase a yes/no question, then roll:
- 1 — No, and something goes worse than expected
- 2 — No
- 3 — No, but there’s a small silver lining
- 4 — Yes, but with a complication
- 5 — Yes
- 6 — Yes, and something goes unexpectedly in your favour
That is a complete, working oracle. The “and” and “but” results are what make it feel alive — they stop the game from being a flat coin-flip and start generating consequences you would never have written yourself.
Adjusting the Odds
Not every question is a 50/50. Weight the roll to match how likely the answer plausibly is.
Asking “is this abandoned tower heavily guarded?” — unlikely. Roll a d6 and treat 1–4 as No. Asking “does the city watch notice a fire in the market district?” — very likely. Roll a d8 and treat only 1–2 as No.
This intuitive weighting is the skill of oracle play. You are not eliminating your judgement, you are using it to set the odds and then letting the dice decide within them.
Asking Better Questions
The quality of a solo session depends almost entirely on the quality of your questions. Two rules:
Ask about the world, not about yourself. “Do I want to open the door?” is not an oracle question — that’s your character’s choice, and it’s yours to make. “Is something waiting behind the door?” is an oracle question.
Ask questions you would genuinely like either answer to. If a “no” would stall the game dead, don’t ask it. Rephrase until both outcomes lead somewhere.
GM Emulators: The Bigger Tools
An oracle answers yes/no. A GM emulator does more — it generates scenes, tracks how chaotic the situation has become, introduces events you didn’t see coming, and manages the threads of an ongoing story. If the d6 oracle is a hand tool, a GM emulator is the workshop.
Mythic Game Master Emulator
Mythic GME is the best known and most widely used GM emulator, and for most players it is the natural next step after the basic d6 oracle. Its central innovation is the chaos factor — a number, typically 1 to 9, that tracks how far events have spiralled out of your character’s control.
The chaos factor does two things. It shifts the oracle’s odds (in a high-chaos game, unlikely bad things become likelier). And it drives random events — moments where Mythic interrupts your plan and injects something you didn’t ask for. A new NPC arrives. A thread you’d forgotten resurfaces. The situation changes under you.
Mythic also maintains two lists you keep as you play: a threads list (unresolved plot hooks) and a characters list (people in play). When a random event fires, Mythic rolls against those lists — so the surprises it generates are rooted in your actual story rather than pulled from nowhere.
It takes a session or two to internalise. The payoff is a solo campaign that genuinely surprises you.
Other GM Emulators Worth Knowing
One Page Solo Engine. A single page. Oracle, scene complications, NPC generator, plot hooks — all of it compressed into one sheet. Excellent if Mythic feels like too much bookkeeping.
UNE (Universal NPC Emulator). Focused entirely on NPCs. Generates a stranger’s mood, demeanour, and motivation, then drives conversations through a structured back-and-forth. Pairs well with any oracle.
Ironsworn’s oracles. Ironsworn is a full RPG, but its oracle tables are free and system-agnostic. Many D&D players lift them wholesale — they’re among the best-designed tables available at any price.
CRGE (Conjectural Roleplaying GM Emulator). Tracks narrative “expectation” and deliberately builds toward reversals. Best for players who want story shape rather than pure randomness.
Random Encounter Generators for Solo Play
An oracle tells you whether something happens. An encounter generator tells you what.
The 5e Dungeon Master’s Guide includes encounter tables by environment and tier, and they work perfectly well solo — with one critical adjustment. Those tables assume a party of four to five characters. A solo character walking into a standard encounter will die, quickly and often.
Scale down hard. As a rule of thumb, a solo character handles encounters built for roughly a quarter of a full party’s strength. Halve monster counts, drop the challenge rating, or give your character an NPC ally to absorb some damage.
Or sidestep the arithmetic entirely by using a game that is already balanced for one player — which is what the next section is about.
Or Skip the Oracle Entirely
Oracles are powerful, but they ask something of you. You are simultaneously the player, the referee, and the world-builder. Some evenings that is exactly what you want. Other evenings you just want to play, and the setup cost is more than you feel like paying.
For those evenings, a purpose-built solo game does the Game Master’s job for you — the structure and the tables are the oracle, already tuned and already balanced for one player.
Deep Delving is a solo dungeon crawler using full 5e mechanics. The dungeon generates itself as you explore, encounters are already scaled for a single character, and 8,000+ boss combinations mean no two runs repeat. No oracle to configure, no chaos factor to track.
Mindscourge goes further still — one player, one d20, no Game Master and no prep at all. Your warband is dead, and the things waiting in the dark are wearing their faces. Four levels down, no way back up.
Want to try the format before spending anything? The Silent Cathedral is a free 5e solo one-shot that teaches every mechanic as it comes up, and Half-Pint runs free in your browser with no dice at all.
Common Oracle Mistakes
Asking questions you’ve already answered. If you know what you want to happen, you’re not consulting the oracle — you’re looking for permission. Roll only on things you genuinely don’t know.
Overriding results you don’t like. The oracle’s whole value is that it isn’t you. If you reroll every unwelcome answer, you’ve built an elaborate machine for agreeing with yourself.
Refusing to interpret. Sometimes a result makes no literal sense in context. That is not a failure — that’s the interesting part. “Unexpected ally appears” in an empty crypt doesn’t mean a person walks in. Maybe it’s a name carved in the wall. Maybe it’s the realisation that the thing chasing you has an enemy. Interpretation is the craft.
Planning the whole adventure first. If you’ve plotted the arc in advance, the oracle has nothing to do. Leave the ending genuinely open.
Quitting after one awkward session. The first oracle session almost always feels mechanical and thin. Session two is usually markedly better. The tools become invisible surprisingly fast.
Frequently Asked Questions
What is a D&D oracle?
A dice-based tool that answers yes/no questions about the world so you don’t have to decide them yourself. It replaces the Dungeon Master’s job of telling you what happens, which is what makes solo play possible. The simplest version is a single d6.
What is a GM emulator?
A more complete system that does everything an oracle does and adds scene generation, random events, and narrative thread tracking. Mythic GME is the best known. Think of an oracle as one tool and a GM emulator as a full toolkit.
Is Mythic GME worth it?
If you want long-running solo campaigns with genuine surprises, yes — the chaos factor and random event system produce story turns you would never have invented. If you mostly want to play tonight without setup, a purpose-built solo game like Deep Delving gets you there faster.
Can you use an oracle with D&D 5e?
Yes. Oracles are system-agnostic — they replace the DM’s role, not the game’s rules. You still roll attacks, cast spells, and track hit points exactly as written. The oracle only answers questions about the world. The one adjustment you must make is encounter scaling: 5e encounters assume a full party, so scale down significantly for a solo character.
How do you handle NPCs without a DM?
Ask the oracle. Before a conversation, roll on whether the NPC is friendly, what they want, and whether they’re telling the truth. UNE (Universal NPC Emulator) automates this with dedicated tables for mood, demeanour, and motivation.
Do I need to buy an oracle?
No. The d6 oracle at the top of this page is complete and free, and Ironsworn’s oracle tables are a free download. Buy Mythic GME only once you know you want a deeper system.