# Cthulhu Dark *Created:* 2026-01-18, *Modified:* 2026-11-02 ![[Cthulhu Dark - 2017 Full Edition (cover).jpg]] ![[Cthulhu Dark - 2010 Pamphlet (cover).jpg]] *Left: the 2017 full edition. Right: the 2010 four-page pamphlet, in full.* **Cthulhu Dark** is Graham Walmsley's four-page answer to the question of how little a Mythos game actually needs. The mechanics fit on a pamphlet: roll some d6, take the highest, and the only stat you own is how much you have seen. There is no combat system because fighting anything you meet kills you, no character advancement because there is nothing to advance toward, and no way to lose an investigation for want of a clue. What is left is the thing Lovecraft's stories are actually about — people learning more than they can carry. It is also the most honest adaptation of the source material the hobby has produced, and the least sentimental: where **[[Call of Cthulhu]]** lets investigators keep their feet under them with skills and luck, this game treats knowledge as an injury that occasionally makes you better at noticing what is about to eat you. ## Setting There is no house setting in the core rules. Cthulhu Dark is a procedure for cosmic-horror investigation in whatever period you drop it into, and the default register is the 1920s of the stories: scholars, journalists and the merely curious pulling at things that were not meant to be solved, in a universe that does not notice them doing it. The tone rule is the whole point — humans are powerless, the truth is not a weapon, and the ending is not a victory. The full edition supplies four worked settings, each with a scenario: - **London 1851 — *Screams of the Children*** — thieves, beggars and other slum dwellers investigating monsters inside the aristocracy. - **Arkham 1692 — *The Doors Beyond Time*** — Lovecraft's town in the era of the witch trials, where superstition is the local common sense. - **Jaiwo 2017 — *The Curse of the Zimba*** — a fictional West African nation in the present day. - **Mumbai 2037 — *Consume*** — cyberpunk India, two decades into a corporate future. ## Mechanics ### The Roll Say what you are doing and roll: - **one die** if the task is within human capabilities, - **one die** if it falls within your occupation's expertise — directly, or, for a highly specific occupation, plausibly adjacent: a florist may recognise a poisonous plant, a quantum physicist may sense patterns behind the universe, - **your Insight die** — green in this edition, the 2010 pamphlet's red Insanity die — if you are willing to risk your mind. You may add it to any roll, not only an obviously dangerous one; on something beyond human capability it may be the only die you roll, and then it is automatically the highest die. The highest die shows how well you do: - **1** — you barely do it. In the book's example you crash the car, but you still arrive in time. - **2** — you do it, although not well. - **3** — you do it adequately. - **4** — you do what you want, and do it well. - **5** — you do it well, and get something extra. - **6** — you do it brilliantly, and the extra may be more than you wanted. A 1, 2 or 3 is **never a failure** — only the **Failure Die** can make you fail. If the **Insight die** is the highest die you rolled, you also make an Insight roll. ### Insight Insight starts at 1. When you see something disturbing — or when your **Insight die** comes up highest — roll a die; if it beats your current Insight, add 1 and roleplay the fear. From 5 upward you can push it back down by suppressing Mythos knowledge: burn the book, break the ritual, impede the investigation, roll the die and drop a point if you roll under. At 6 you go incurably insane: play the character's last moments however you like, then make a new one or retire them. There is also a faster variant for quick play: treat adding the **Insight die** to any roll as an immediate Insight roll, rather than waiting to see whether it is the highest die. It is quicker at the table and it makes Insight climb faster. The mechanic runs backwards from what Mythos players expect, and deliberately. In **[[Call of Cthulhu]]** low Sanity makes further loss more likely; here high Insight makes further gain *less* likely, because you have already seen most of what there is to see. The full edition calls it Insight rather than Insanity for exactly that reason — you are accumulating understanding, not pathology — which also keeps the game off a clinical vocabulary it has no business using. ### Investigation An investigation never stalls for want of a clue. The highest die tells you how much you learn, and the upper bands are **cumulative** — each includes everything below it: - **1** — the minimum useful information, and no more: a few words, an address, enough to continue. - **2** — the same, in brief: a sentence or two, essentially what you need. - **3** — most of it, but not all: two or three sentences. - **4** — everything a competent investigator would discover. - **5** — all of that, plus something more. - **6** — all of that, plus a glimpse beyond human knowledge; in the book's example you experience one of the visions yourself. Low rolls aren't failures here either. On a 1, 2 or 3 you get what you need, but not necessarily the way you wanted it: you find out where the quarry went, and draw attention to yourself doing it. That "you always find the clue" move is lifted, by the author's own account, from GUMSHOE — **[[Trail of Cthulhu]]** solves the same problem with point-spends; here it is one die. ### Failure, Rerolls, and Other People - **The Failure Die is the only way to fail.** Anyone at the table — player or Director — can call failure when they think the story would be more interesting for it: say how it might go wrong and roll a die. If it beats your highest die, you fail as described; **a tie is a success.** - **Failure has to be worth having.** Failing to read a manuscript is rarely more interesting than reading it, and getting caught picking a lock isn't automatically interesting either. When nobody is sure, talk it over as a group — and if you decide it isn't interesting, don't roll the **Failure Die** at all. - **Two different failures, two dice.** If different people have different failures in mind, both roll and the highest die decides which one happens. - **One die against a whole group.** When several Investigators attempt the same thing, roll a single **Failure Die** against all of them: equal or higher succeeds, lower fails. That is the usual way to handle a room full of Investigators fighting at once. - **Rerolling** — if your **Insight die** was in the roll you may reroll everything, and if it wasn't you may add it and reroll. The Insight-roll trigger still applies to the new result. - **Cooperating and competing** — cooperating, everyone rolls and the single highest die among you decides the outcome. Competing, highest wins; a tie goes to the higher Insight, and if that ties too, reroll. ### Combat The four-page rules are blunt: *"If you fight any creature you meet, you will die."* No hit points, no initiative, no order to lose — you roll to hide, to run, or to get out of the room, and the die tells you how much dignity you keep. The full edition keeps the spirit and sharpens the edge: fighting a supernatural creature *to defeat it* is still fatal, but fighting people, or a monster you only need to get past, is rolled like anything else. ## Editions - **Cthulhu Dark** (2010) — the four-page rules pamphlet: investigator, Insight, the roll, investigating, failure, rerolls, cooperation, suppression and going insane. Free, self-published, layout by Brennen Reece. *In the library.* - **Cthulhu Dark Tales** (2011) — companion booklet on the consequences of knowledge: what each die result buys you in information, and playing the other people whose letters and diaries you find. *In the library.* - **Cthulhu Dark (full edition)** (2017, Kickstarter) — the pamphlet grown into a 199-page book from **Thieves of Time**, by Graham Walmsley with **Kathryn Jenkins** and **Helen Gould**, who wrote Arkham 1692 and Jaiwo 2017 respectively, each with its scenario. It renames the Insanity die to the **Insight die**. *In the library.* - **Player's Section** — the rules, unchanged from the pamphlet. - **Director's Section** — cosmic horror and Insight; writing a mystery; running it; the threats of the Mythos. - **Four settings, four scenarios** — the settings above, each with a full scenario attached. - **Appendices and handouts** — hacking Cthulhu Dark, design notes, and the letters, confessions and diaries the scenarios hand out. - **Cthulhu Dark investigator sheet** (2012) — a one-page fan-made investigator sheet, unattributed. *In the library.* ## References - [The original rules (free PDF) - Catch Your Hare](http://catchyourhare.com/files/Cthulhu%20Dark.pdf) - [Cthulhu Dark (full edition) - DriveThruRPG](https://www.drivethrurpg.com/en/product/341997/cthulhu-dark) - [Cthulhu Dark - Graham Walmsley on the Kickstarter - Pelgrane Press](https://pelgranepress.com/2017/06/01/cthulhu-dark) - [Review of the game's mechanics and tone - The Indie Game Reading Club](https://www.indiegamereadingclub.com/indie-game-reading-club/cthulhu-dark/) - [Purchase the physical book - Indie Press Revolution](https://www.indiepressrevolution.com/xcart/Cthulhu-Dark-Print-PDF.html)