Why GURPS Works Alone
The GURPS Basic Set is written for a Game Master and a group of players, and it has no chapter on solo play. Yet GURPS is a surprisingly good solo system. Its rules are a consistent "physics engine": once you know a character's skill and the situation's modifiers, the dice tell you what happens, with no GM judgment required. It also comes with two tools that solo players usually have to invent: the Reaction Table, which tells you how an NPC feels about you, and self-control rolls, which tell you when your own disadvantages take over. What's left is something to answer the questions a GM would normally answer. That's an oracle.
The Flight Simulator
Earlier parts compared GURPS to a precision toolkit. Playing solo, it works like a flight simulator: you're the pilot, but you don't get to decide the weather. The rules handle the physics, the oracle handles the weather, and your job is to fly the plane as your character would.
What You'll Find in This Part
- A yes/no oracle built on GURPS's own 3d6 roll, with the exact odds
- Scene checks that stop you writing a story you already know
- How to run NPCs and combat fairly when you're also the GM
- How reaction rolls and self-control rolls do a GM's job for you
- A step-by-step routine and a worked example for your first solo session
Your Solo Kit
You don't need anything GURPS doesn't already use:
- Three six-sided dice (or the dice roller). They run your success rolls, the oracle and the reaction rolls.
- The rules. GURPS Lite, the free summary from Steve Jackson Games, is plenty to start. The Basic Set adds the full options when you want them.
- One character, built with character creation. Advice on solo builds follows below.
- A notes file or index cards for NPCs, locations, open questions and threads.
- A journal. Writing the story down is half the fun of solo play, and it's how you remember threads between sessions.
💡 Tip: General-purpose GM emulators such as Mythic Game Master Emulator (Word Mill Games) work with GURPS too. This part sticks to an oracle built from GURPS's own 3d6 roll, so you can start without buying anything. For solo play in general, see Ray's Solo RPG Mastery guide.
The 3d6 Oracle
The oracle is just a success roll. Ask a yes/no question you genuinely don't know the answer to, decide how likely "yes" is, and treat that as an effective skill. Roll 3d6: at or under the target means yes, over it means no. Then read the margin the way you'd read any GURPS roll:
- Made it by 5 or more, or rolled 3–4 → Yes, and… Yes, plus something extra in your favor.
- Made it by 1–4 → Yes.
- Rolled exactly the target → Yes, but… Yes, with a complication or cost.
- Missed by exactly 1 → No, but… No, with a consolation or an opening.
- Missed by 2–5 → No.
- Missed by 6 or more, or rolled 17–18 → No, and… No, and things get worse.
Setting the Odds
Pick the target from how likely the answer seems in the fiction. These are the exact odds with 3d6, worked out from all 216 possible rolls (rounded to one decimal place):
| Likelihood (target) | No, and… | No | No, but… | Yes, but… | Yes | Yes, and… | Any yes |
|---|---|---|---|---|---|---|---|
| Very likely (14) | 1.9% | 2.8% | 4.6% | 6.9% | 46.3% | 37.5% | 90.7% |
| Likely (12) | 1.9% | 14.4% | 9.7% | 11.6% | 46.3% | 16.2% | 74.1% |
| Toss-up (10) | 4.6% | 32.9% | 12.5% | 12.5% | 32.9% | 4.6% | 50.0% |
| Unlikely (8) | 16.2% | 46.3% | 11.6% | 9.7% | 14.4% | 1.9% | 25.9% |
| Very unlikely (6) | 37.5% | 46.3% | 6.9% | 4.6% | 2.8% | 1.9% | 9.3% |
A toss-up at 10 is a true coin flip, because exactly half of all 3d6 rolls are 10 or less, and its outcomes mirror each other perfectly. The "but" answers sit right on the edge of the target, so close calls produce complications rather than flat answers. That keeps a solo story moving.
🎲 Try the Solo Tools
NPC Reaction
Self-Control Roll
Session Log
- Your rolls will appear here.
Running Scenes Solo
A solo session is a chain of scenes. Each one starts with what you expect to happen and ends when its question is answered.
The Scene Check
Before each scene, decide what you expect to happen, then roll 3d6 once. This is a simple house rule inspired by GM emulators, not a GURPS rule:
- 3–6 (9.3%): Interrupted. Something different happens. Use a random spark or one of your disadvantages for inspiration.
- 7–9 (28.2%): Altered. The scene happens, but one detail is different: someone extra is there, the location has changed, or the timing is off.
- 10–18 (62.5%): As expected. Play it as you imagined.
Use Only the Rules You Need
Solo, you're running both sides of every roll, so rules detail costs you twice. Start with the core rules from GURPS Lite: success rolls, Quick Contests, simple combat. Add optional rules (hit locations, detailed encumbrance, the tactical map) only when a scene really benefits from them. Part 11's advice on taming complexity applies double here.
Running the Opposition
The hardest part of solo play is staying fair to the other side. GURPS makes this easier than most systems, because nearly everything is a number you can set before you roll.
Set Modifiers Before You Roll
Decide the modifier for a task from the situation, using the same scale a GM would: a bonus for easy or well-prepared tasks, nothing for routine ones under pressure, and growing penalties for hard ones. Write the number down before you roll, and don't change it after. If you can't decide between two modifiers, let the oracle choose: "Is the lock a cheap one?"
Let NPCs Roll for Themselves
When an NPC actively opposes you, roll for them exactly as a GM would: their defenses against your attacks, their Will against your Intimidation, a Quick Contest of Stealth against your Perception. A few rough skill levels make quick NPCs easy (a rule of thumb, not an official table):
- Mooks (thugs, guards): key skills around 10–12, Dodge 8, nothing fancy.
- Professionals (veteran soldiers, skilled rivals): key skills around 13–15.
- Masters and bosses: key skills 16 or more, built like a full character.
The Reaction Table Is a Built-In Oracle
Whenever you're unsure how an NPC feels about you, don't decide: make a reaction roll. Roll 3d6, add your Appearance, Charisma, Reputation and situation modifiers, and read the Reaction Table: 0 or less Disastrous, 1–3 Very Bad, 4–6 Bad, 7–9 Poor, 10–12 Neutral, 13–15 Good, 16–18 Very Good, 19+ Excellent. It's the same table a GM uses, so it's perfectly fair. Use the oracle for specific questions after that: "Does the Poor-reacting clerk at least point me to the records room?"
Combat and Morale
Run fights exactly as written: both sides choose maneuvers, roll attacks and active defenses, and take real damage. To decide what an enemy does, pick the move that fits their goals and skill, or ask the oracle ("Does the second thug run for help?"). GURPS has no core morale rule, so here's a useful house rule: when a group loses its leader or half its number, roll against their Will (10 for ordinary mooks). On a failure they flee or surrender.
Disadvantages with One Player
At a table, the GM and other players remind you to play your disadvantages. Solo, the rules do it for you.
- Self-control rolls. Many mental disadvantages (Curious, Greed, Bad Temper, Overconfidence and others) have a self-control number. When the disadvantage is triggered, roll 3d6 against it. Succeed and you resist; fail and you act as the disadvantage demands. Odds: 6 = 9.3%, 9 = 37.5%, 12 = 74.1%, 15 = 95.4%.
- Ask the oracle about triggers. If you aren't sure a situation should trigger a disadvantage, ask: "Does this sealed crate count as a mystery worth investigating?"
- Play your quirks. They're only worth a point each, so they're easy to forget. Mention one every scene.
- Award character points honestly. A GM usually gives a few points per session. Solo, pick a modest, fixed award (for example 2 points) before you play, plus 1 extra when you played your disadvantages even though they hurt. This is a house rule; the point is to decide it before you know how the session goes.
⚠️ Watch out: The most common solo mistake is skipping self-control rolls when they're inconvenient. If your disadvantages never cost you anything, they were free points.
Building a Character for Solo Play
A lone hero has no one to drag them out of trouble, so build with that in mind.
- Give yourself more points, or a friend. 150 points works for gritty stories; 200–250 gives a lone character more room to survive. Alternatively, buy an Ally, an NPC companion you control in play, so you have someone to talk to and someone to cover your back.
- Cover the basics. A solo character needs some way to fight or flee, some way to talk, and some way to find things out. Gaps hurt more without a party to fill them.
- Survival advantages earn their keep. Luck [15], Combat Reflexes [15], High Pain Threshold [10] and Danger Sense [15] all matter more when nobody else is watching your back.
- Contacts are your party. Contacts and Patrons give you NPCs to ask for information and help, and the reaction and oracle rolls decide how helpful they are today.
- Pick disadvantages that drive stories. Curious, Sense of Duty, Code of Honor, Enemies and Obsession all push your character into scenes. Disadvantages that only make you sit at home are dull solo.
🛠️ How To: Your First Solo Session
- Build one character with GURPS Lite or the Basic Set, using the solo advice above.
- Write a one-line problem. "Someone is stealing artifacts using my research." That's the session's question.
- Frame the opening scene. Where are you, what do you want right now, and what's in the way?
- Make a scene check. Adjust the scene if it's altered or interrupted.
- Play. Roll skills for actions, Quick Contests against NPCs, reaction rolls for strangers, and the oracle for everything you don't know.
- Close the scene when its question is answered. Note new NPCs, clues and open questions.
- Repeat until the problem is resolved or you reach a good cliffhanger. Then award your character points and write a short journal entry.
Example of Play
Dr. Rita Anderson (IQ 14, Will 14, Diplomacy 14, and both Curious (12) and Honesty (12) among her disadvantages) is chasing whoever is using her research to find artifacts.
Scene: Rita expects to search a rival's office after hours. Scene check: 8, Altered. She decides the office isn't empty: a security guard is making his rounds.
Reaction: The guard doesn't know her. Rita has no Appearance or Reputation modifiers here, but she's in a building where she gave talks last year, so she takes +1. Roll: 9 + 1 = 10, a Neutral reaction. He's not hostile, just doing his job.
Action: Rita's Honesty means she won't sneak or lie, so she tells the guard the truth: her stolen research may be in that office, and she'd like him to watch while she looks. Diplomacy is an Influence roll, a Quick Contest against the guard's Will 10. She rolls 9 (made it by 5); he rolls 12 (missed by 2). Rita wins, and the guard unlocks the door.
Question: "Is there anything here about my stolen research?" It's her rival's office, so Rita sets it as Likely (12). Roll: 12, exactly the target: Yes, but… Her stolen notes are here, but they're in a crate that's been sealed for shipping.
Self-control: The smart move is to leave and call the police. But a sealed crate full of her own research is exactly the kind of mystery her Curious (12) can't resist. She rolls against 12 and gets a 14: she fails. She won't break the seal (that would trigger her Honesty), but she stays to copy every shipping label and customs form she can find. She's still reading when the guard's radio crackles: her rival is on his way up.
Common Questions
Isn't it boring to know everything already?
You won't. The oracle, scene checks, reaction rolls and NPC rolls answer the questions you'd normally leave to a GM, so you're discovering the story as you play. Only decide what you would decide as a player.
What if the oracle gives an answer that makes no sense?
Reinterpret it before you reroll. A "yes" that seems impossible often hides a twist. If it truly breaks the story, treat it as a "but" answer or ask a smaller question.
Should I play one character or a group?
Start with one, perhaps with an Ally. A whole party works, but GURPS characters carry a lot of detail, and every extra sheet adds bookkeeping.
How do I avoid fudging for my character?
Set modifiers and NPC skills before you roll, roll in the open (even if only you can see), and honor self-control rolls and injuries. When in doubt, ask the oracle rather than choosing.
Is GURPS too detailed for solo play?
Only if you use every rule. With the core rules from GURPS Lite and the tools on this page, a solo scene moves quickly, and the detail is there when a fight or a climb really matters.
Key Takeaways
- GURPS has no solo chapter, but its consistent rules make it easy to play alone with a simple oracle.
- The 3d6 oracle is a success roll: set a target from how likely "yes" is, then read the margin, with "but" answers on close calls.
- Scene checks and random sparks stop you from writing a story you already know.
- The Reaction Table and self-control rolls already do a GM's job: use them instead of deciding.
- Set modifiers and NPC skills before rolling, and keep the rules as light as the scene allows.
📓 Journal Prompts
After your first solo session, jot down:
- Which oracle answer surprised you most, and what did it change?
- Did a self-control roll go against you? How did it shape the story?
- Were any modifiers or NPC skills too easy or too hard?
- What open questions or threads do you want to pick up next time?