Why ICRPG Works Alone
Index Card RPG is written for a GM and a table of players, and its core book has no solo chapter. But few games are easier to run by yourself. Every room has one Target, so you never juggle difficulty tables. Effort turns every obstacle into a countdown you can see. And timers do much of a GM's job for you: once a timer is ticking, the room pushes back whether or not anyone is running it.
What's left is answering questions and building rooms you don't already know. For that you need an oracle, and this guide's D.E.W. checklist (Danger, Energy, Wonder) makes a perfect room generator.
The Index Card Is Your GM
At a table, the GM flips over an index card and describes the room. Solo, you write the card yourself, then let the dice fill in what you don't know. One card, one Target, one timer, and a few rolls to surprise you: that's a whole scene.
What You'll Find in This Part
- A yes/no oracle built on ICRPG's own Target, EASY and HARD, with exact odds
- Room checks and D.E.W. sparks for building rooms on the fly
- How to run monsters, timers and loot when you're also the GM
- A step-by-step routine and a worked example for your first solo session
Your Solo Kit
- Your dice (d4 to d20), or the dice roller.
- Index cards for rooms, monsters and loot. The fillable cards work too.
- One hero, built with character creation or picked from the ready-made characters.
- The rules. ICRPG Master Edition has everything; the Quick Reference covers the basics.
- A journal to remember threads between sessions.
đź’ˇ Tip: General-purpose GM emulators such as Mythic Game Master Emulator (Word Mill Games) work with ICRPG too. This part sticks to dice and tables built from ICRPG's own ideas. For solo play in general, see Ray's Solo RPG Mastery guide.
The Target Oracle
Treat a question like a roll against a room Target. Ask a yes/no question you genuinely don't know the answer to, and pick how likely "yes" is. A toss-up is Target 11. Making it EASY or HARD shifts it by 3, just like any attempt:
- Very likely (EASY twice): 5 or higher
- Likely (EASY): 8 or higher
- Toss-up: 11 or higher
- Unlikely (HARD): 14 or higher
- Very unlikely (HARD twice): 17 or higher
Roll a d20 with no bonuses, then read it:
- Natural 20 → Yes, and… Yes, plus something extra in your favor.
- Target +2 or more → Yes.
- Exactly the Target, or 1 over → Yes, but… Yes, with a complication or cost.
- 1 or 2 under the Target → No, but… No, with a consolation or an opening.
- Further under → No.
- Natural 1 → No, and… No, and things get worse.
The Odds
Every face of a d20 is equally likely (5%), so these odds are exact:
| Likelihood (Target) | No, and… | No | No, but… | Yes, but… | Yes | Yes, and… | Any yes |
|---|---|---|---|---|---|---|---|
| Very likely (5+) | 5% | 5% | 10% | 10% | 65% | 5% | 80% |
| Likely (8+) | 5% | 20% | 10% | 10% | 50% | 5% | 65% |
| Toss-up (11+) | 5% | 35% | 10% | 10% | 35% | 5% | 50% |
| Unlikely (14+) | 5% | 50% | 10% | 10% | 20% | 5% | 35% |
| Very unlikely (17+) | 5% | 65% | 10% | 10% | 5% | 5% | 20% |
The table mirrors itself: "Likely" says yes exactly as often as "Unlikely" says no, and a toss-up is a true coin flip. The "but" answers sit right next to the Target, so close calls bring a twist instead of a flat answer.
Building Rooms Solo
An ICRPG adventure is a chain of rooms. Solo, you build each one as you reach it.
The Room Check
As you enter a room, decide what you expect to find, then roll a d6. This is a simple house rule, not an ICRPG rule:
- 1 (about 17%): Interrupted. Something else is here. Roll a D.E.W. spark and build the room around it.
- 2–3 (about 33%): Altered. The room is what you expected, but one detail is different.
- 4–6 (50%): As expected. Write the room as you imagined it.
The D.E.W. Spark
When you need ideas, roll a d6 on each of these tables to give the room some Danger, Energy and Wonder, this guide's room checklist from Room Design. They're this guide's tables, not official ones; swap in your own as your world grows.
Danger (d6)
- A pit or a collapsing floor
- A monster lying in wait
- Poison gas or choking smoke
- A trap guarding the way out
- A rival crew after the same prize
- The room itself is flooding or burning
Energy (d6)
- A timer is already ticking (d4 rounds)
- Enemies arrive in d4 rounds
- Something is chasing you in
- The only exit is closing
- Someone needs help right now
- The light is going out
Wonder (d6)
- A statue that moves when unwatched
- An ancient, humming mechanism
- A glowing pool with something at the bottom
- An object that talks
- A window onto somewhere else
- Treasure that isn't what it seems
One Target, One Timer
Set the room's Target before you roll anything, and write it on the card: around 10 for a simple room, 12 for most, 13 or 14 for a dangerous one, 15 or more for a deadly one (this guide's rule of thumb). Then give the room a timer whenever something is coming, from a d4 for "any moment now" to a d6 or a fixed number of rounds. A ticking timer is the best way to keep a solo scene honest: you can't dawdle when the water is rising.
🎲 Try the Solo Tools
Session Log
- Your rolls will appear here.
Running Monsters and Loot
Monsters Roll for Themselves
Monsters in ICRPG attack by rolling d20 plus their bonus against your Defense. Solo, roll for them exactly as a GM would, and track their hearts on their card. To decide what a monster does on its turn, pick the move that fits it, or ask the oracle: "Does the wolf go for the weakest target?"
Let the Oracle Speak for NPCs
When you're not sure how someone reacts, ask: "Does the gatekeeper believe me?" Set the likelihood from what they want and what your hero has done. If your hero actively tries to convince them, that's an attempt like any other: d20 + CHA against the room's Target.
Loot Is Your Reward
Loot is how ICRPG heroes grow, and solo is no different. When you beat a boss, finish a hard room or reach a goal, roll on the Loot Generator or your world's loot tables, and write the item on a card. Hand out milestone rewards when a big goal is met, just as a GM would.
Building a Hero for Solo Play
- Cover the basics. A lone hero needs a way to fight, a way to get past locks and traps, and a way to talk.
- Defense matters more. With no one else to draw attacks, armor and a shield buy you time.
- Consider a companion. A loyal follower, a pet or a hireling gives you someone to talk to and someone to watch your back. Run them as a simple NPC card.
- Pick a goal that starts stories. A hero chasing something specific always knows which door to open next.
🛠️ How To: Your First Solo Session
New to the game? Play Your First Adventure first: a ready-made ten-card solo game on the page that teaches the rules as you go. Then come back and build your own.
- Make one hero, or pick one from the ready-made characters.
- Write a one-line goal. "Recover my family's stolen sword from the goblin warren." That's the session's question.
- Picture the first room and make a room check.
- Write the room card: one Target, a timer if anything's coming, and a D.E.W. spark if you need ideas.
- Play. Make attempts against the Target, roll Effort, roll for monsters, and ask the oracle about everything you don't know.
- Take the loot and note any new threads, then move to the next room.
- Stop when the goal is met or at a good cliffhanger, and write a short journal entry.
Example of Play
Vera "Ironwall" Stone, the fighter from Character Examples (STR +3, 1 heart, Defense 13, Weapons Effort d6), is hunting the goblins who stole her family's sword.
Room check: Vera expects an empty guard post. She rolls a 2 on the d6: Altered. She decides the post isn't empty: a single goblin sentry (a Standard foe with 1 heart, tougher than the usual goblin minion) is dozing by a brazier.
Room card: Target 12. Energy: if the sentry wakes, the rest of the warband arrives on a d4 timer.
Question: "Is the goblin chief nearby?" It's a toss-up (11+). She rolls 10, one under: No, but… The chief isn't here, but the sword's scabbard hangs on the wall.
Attack: Vera strikes the sentry: d20 + STR 3. She rolls 11, for 14 against Target 12: a hit. Weapons Effort: she rolls a 5 on the d6, and the sentry drops to 5 of its 10 HP.
Monster turn: The goblin swings back: d20 + 2 against her Defense 13. It rolls 9, for 11: a miss. But it shrieks, so the d4 timer starts: Vera rolls a 3. In three rounds the warband is here.
Common Questions
Isn't it boring to know everything already?
You won't. Room checks, D.E.W. sparks, the oracle and the monsters' own rolls answer the questions you'd normally leave to a GM, so you discover the dungeon as you go.
What if the oracle gives an answer that makes no sense?
Reinterpret it before you roll again. 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 hero or a whole party?
ICRPG characters fit on one card, so two or three heroes are very manageable solo. Start with one, add a companion, and grow from there.
How do I avoid fudging for my hero?
Write the Target and timer on the room card before rolling, roll monsters' attacks in the open, and let timers run out. When in doubt, ask the oracle rather than choosing.
Key Takeaways
- ICRPG's one Target per room and visible timers make it unusually easy to run alone.
- The Target oracle uses Toss-up 11, with EASY and HARD shifting it by 3, and "but" answers right at the Target.
- Room checks and D.E.W. sparks build rooms you didn't plan.
- Roll for monsters as a GM would, and keep loot flowing as your reward.
đź““ Journal Prompts
After your first solo session, jot down:
- Which room surprised you most, and what made it?
- Did a timer run out? What did it change?
- Were your Targets too easy or too hard?
- What loot and threads will you follow next time?