Call of Cthulhu Hack – PDFs

Lovecraft fan art "The call"

I’ve been working on a hack of Call of Cthulhu by Chaosium that is backward compatible but also simpler and a bit more reasonable than their 7th Edition system. Meaning no offence, there’s just some redundancy there. Then I decided to use a version of the Stress system from Mothership as a more interesting way to handle Sanity damage. A few more tweaks, and there you have it. I have a character sheet, a character creation worksheet, and a rules reference for the reworking of the rules. I’ve run it past one veteran CoC Keeper who liked it, and it’s what I’ll use next time I run Call of Cthulhu. Here you go! Enjoy. As always, comments welcome.

CoC Hack Character Creation Worksheet 0.3

CoC Hack Character Sheet 0.4

CoC Hack Rules Reference Sheet 0.4

These are unfinished, and not near publishable, even if I could publish them, but as notes you could use them to run a Call of Cthulhu game, including a published campaign almost exactly as written.

Horror Gaming

Call of Cthulhu (role-playing game) - Wikipedia

I think that the hardest kind of RPG experience to create at the table is horror – by a significant margin. I’ve been alarmed, worried, disgusted, and so on at the table, but very rarely frightened. The most frightened I remember being was in an Old World of Darkness game using Kult’s setting. The game that is always recommended is Dread, which is a great use of Jenga to create tension at a table whether you want it or not. It still requires more elements to approach horror.

I wonder – it’s pretty easy for a movie to scare the crap out of me. Why is it so much harder at a table?

Players Must Buy In/Session Zero

I’m pretty funny – I can coax someone into participating in a funny game. I can coax someone into participating in a heroic adventure game. I even know how to design specifically for either goal, among a few others. Horror, though – I don’t know how to coax someone into a horror game, and I can see ways that horror more than other genres would press against players’ lines and veils.

For this reason, a Session Zero for a horror game is necessary. The discussion of what you want kept out of the story needs to be had, because it will likely be the job of the GM in a horror game to suddenly introduce disturbing imagery and themes. It also occurs to me that a tool like the X-Card should be available, but in the context of a horror game, I can see that using it would potentially take people out of the moment – like pausing a horror DVD to answer the phone. And of course we shouldn’t harm each other for the sake of playing pretend, but if we can figure things out ahead of time, that is especially good in the context of a horror game.

Hope Must be Limited

The reason we sat down and designed Reckoning, a dice-less horror RPG, was because of the problem of dice. As long as you can roll dice to have a chance to triumph, horror is almost impossible. Our players would grin their way through horrific scenarios, or so we thought them, rolling dice all the way. My friend Jason says that a horror game can therefore never use dice, but I wouldn’t go that far. It’s just that dice can’t be an option for triumphing. Stakes have to be set carefully, perhaps.

Reckoning limits hope by having a scene count-down which will end with something horrific happening. Each time a card gets turned, you know something else bad is going to happen, all getting closer to the worst thing happening. I think that some kind of countdown, some kind of visibly growing threat, could be necessary. The proverbial ticking time-bomb that the players know about, even if the characters do not.

Doom Must be Foreshadowed

Continuing on with the previous thought – when you go to a horror movie, or pick up a horror novel, you know what kind of story it is. This has to be clear from the start with a horror game as well. Even if not from the literal beginning, there should be a big reveal at some point, early. Ideally, all of the players should think, “Oh crap, this is going to be deliciously bad.”

If possible there should be foreshadowing both in the fiction and outside of it – in the room where the game takes place. On the character sheet. On the pages of rules you reference during the game. On the art you use to represent what the characters see. In the music you have playing while you game.

A Strong GM Seems to be Necessary

I asked Twitter to let me know about any APs tweeps are aware of that represent a horror game that seemed to really foster fear and horror on the parts of the players. I enjoy APs, but they are generally what I end up doing when I run horror – some moments of squick and then dark humor the rest of the time, bordering on outright zaniness. Even for AP groups that focus on horror gaming, this seems to be where they max out as well. When done well, the squick is very squick-y and the dark humor is dark and funny, but would I call it horror? I’m not sure.

One thing I’ve noticed is that horror gaming, even the squick/dark humor kind, seems to demand a strong GM. I would love to see an attempt at a GM-less (or GM-full) game that does horror consistently well. My guess would be that if it does, it is simply a game (like many GM-less/full games) that attracts a bunch of GMs as players. I think horror gaming will simply depend on GM skill + player buy-in, full stop. I don’t see a way around that, and I don’t see any game that gets around that, though I’d be happy to be proven wrong by some genius game design. As I sit here, that game design is beyond me as a designer.

It’s Cthulhu and Footnotes

The last thought I have about horror gaming is that Call of Cthulhu dominates horror gaming the way D&D dominates fantasy adventure gaming. Clearly, there are other popular horror games, like All Flesh Must Be Eaten back in the day, or Bluebeard’s Bride; various Worlds of Darkness, or of course the often-mentioned Dread. There is also Monsters and Other Childish things, perhaps, or Clockwork: Dominion. But Call of Cthulhu looms over all of these, and when horror gaming comes up, CoC will almost invariably come up as well.

What is the difference here? What makes Call of Cthulhu stand out, despite being temporarily supplanted by Vampire the Masquerade for example? I think one difference is that many of those other games are also about adventure and the chance to triumph. Not Bluebeard’s Bride, and mostly not Dread perhaps, but otherwise, those games listed above can be played as adventure or comedy pretty easily. Really, the one that would be hard to play that way would be Bluebeard’s Bride – I think one could easily hack Dread to tell a Fiasco-style story, as an example.

I think that the key appeal of Call of Cthulhu for horror gaming might be that it is common knowledge that CoC is not about triumphing, or even in many cases surviving, a horror story. It is about going insane and/or dying horribly. The worst things you’ll encounter you cannot possibly overcome no matter what you do. So the game is about progressively learning what those awful things are, and then having a good time on the way down after that. This, even more than the Mythos, is what keeps Call of Cthulhu in that top slot, I think. At least, when I look at horror APs and talk to people about horror gaming.

What Did I Miss?

These are just my thoughts, neither exhaustive nor meant to be so. What did I miss? What has been your experience of horror gaming?

RPG Mechanics Round-Up #13: Call of Cthulhu

Start With A Bang

A house rule for Call of Cthulhu – at character creation, you can reduce your starting Sanity to increase your starting Cthulhu Mythos rating. Maybe 2 Sanity for 1 Cthulhu Mythos, and definitely for a limited amount. But in listening to APs, I feel like rolling against a 5% Mythos rating is less interesting than, say, 15% or 20%.

You could even have a situation where an investigator thinks of themselves as something of an expert. Of course, this will just invite greater disaster. They might become more likely to seek out elements of the Mythos because it is slightly more likely, though still not very likely, that they will understand what they find. Which, of course, is horrifying.

Brush With the Occult

One thing I liked about character creation in Kult (in a previous edition, anyway) was that part of it was describing a brush with the occult. This is a chance for the player to be evocative, and also a chance to add details or threads to the world that could grow into something greater. Leaving little gifts for the Keeper.

Driven By Need

I has occurred to me, running Call of Cthulhu and playing a bit and listening to APs, that investigators so often lack the motivation to do what they do. Sure, they’re curious to an unhealthy degree, but at a certain point, running away and ditching the case is what almost anyone would do.

So what I thought is that in designing a Call of Cthulhu character, a player should name something that the character desperately needs. Money is an easy one Рand Mythos lore and artifacts would of course be incredibly valuable out in the world. Or perhaps the seek a way to resurrect a dead loved one, or get revenge on someone otherwise unreachable. It has to be something  you need so much that continuing on even as you learn of greater horror will seem like a reasonable choice.

OSR Call of Cthulhu

I’ve been thinking about the OSR, and how that design mentality could be applied to games that aren’t D&D. Other older games also had different sensibilities from more modern games, or even more modern incarnations of those games.

That being said, Call of Cthulhu hasn’t changed that much over time. It is still, in some ways, an old school game. I think the design goals of OSR could be applied to Call of Cthulhu, however, as it is a game that would benefit from some simplification, some rulings over rules, and even a clearer focus on player challenge in addition to character challenge.

I have a few thoughts sketched out which I would like to expand later, but here we go:

  • Spend Sanity to push a roll, in contrast to the Pulp Cthulhu mechanic. This should also drive characters to be on track to die or go insane at around the same time. The justification is you do crazy things to avoid dying, pushing yourself closer to the horrors of the Mythos.
  • Combine Strength, Constitution, and Size into something like Body or Fortitude. Then you just need Dexterity, Luck, Psyche (to replace Power), and Education. Leave out Intelligence because you’ll be relying on the player’s intelligence more, while the character can still know things the player doesn’t know, or have skills the player doesn’t have (Education).
    • Magic points, if you are using them, are Psyche/5
  • A shorter and simplified skill list. A problem I see with Call of Cthulhu in every variation I’ve played is that overlap between skills is ignored and the skills given are highly specific, easily leading to characters who should be experts appearing less so because they don’t have one particular skill.
  • Antiquity, Athletics, Charm, Coercion, Credit Rating, Dodge, Fighting, Firearms, Languages, Occult, Physical Sciences, Profession (Art, Drive, Repair, Pilot, Law, Photography…), Psychoanalysis, Social Sciences, Streetsmarts, Weird Science
  • Use a stress system similar to that used in Mothership. Separate insanity and mental illness. In brief, you take Stress, and then make periodic Panic checks instead of Sanity checks. I prefer this, just to avoid the language of sanity/insanity in describing what happens in a CoC game, which tends to overlap mental illness in problematic ways
  • Hit Points are equal to Body/5


RPG Mechanics Round-Up #11

Out of Combat Advantage

The scene is that your adventurers are taking a break from danger, hanging out in town. There is some kind of local festival happening, and they decide to enter the various contests. The ranger joins an archery contest. It doesn’t make sense to me that the ranger would roll the same thing that she would when she is in a life-or-death combat situation – I think of studies showing that the most accurate police officers, the NYPD, still miss 2/3 of the time when they use their weapons. These are people who know what they are in for, train regularly, etc., who probably do great when they are at the gun range. So it occurred to me that in a situation where a D&D-style adventurer is using an adventuring skill in a safe environment such as a local fair, she should roll with advantage. This is also a way to let PCs shine in comparison to locals who only shoot at stationary targets and the occasional rabbit or deer.

Fixing Call of Cthulhu Sanity (Again)

There are obviously problems with Call of Cthulhu’s Sanity system: all of the problems of any hit points style system for modeling trauma; it can be problematic with regard to real-world mental health; it is hard to get players to act against themselves when suffering a bout of madness; the madness that you suffer might come from a list or a table, and therefore feel arbitrary.

As a way to address three out of these four concerns, I thought that it would be interesting to just treat Sanity as hit points. When you run out you can’t play anymore. But when you lose Sanity, take Sanity ‘damage’, you can choose to ‘soak’ some of that damage by taking on a bout of madness. The player chooses the madness that makes sense, maybe from a list the Keeper provides. This way players who want to power through and keep control of their characters can do so, but they will take big hits to Sanity (and for this rule, I would basically double Sanity damage as written). Otherwise, players get a say in what happens, which hopefully gives them buy-in, which hopefully makes them more likely to actually play the insanity to the hilt.

In systems other than Call of Cthulhu, even like D&D, the idea I would use is to provide XP when a character suffering from madness acts against their own best interests.

This also makes me take a moment to consider my house rule for Hold Person type spells. Hmm…

Social Abilities and Hierarchy

I like the idea that social skills function differently when interacting across a social hierarchy (it’s why I designed Parsec that way). Taking D&D’s social proficiencies as an example (Deception, Intimidation, Persuasion), I might say that all three work best with someone who shares your place in the hierarchy; Deception works when dealing with someone higher than you (“Of course, m’lord”); while Intimidation is the default when dealing with someone beneath you (“You address me as ‘Your Grace'”). If you are using those social skills in other ways, you roll with disadvantage (a pauper Intimidating a Prince, a Prince trying to Persuade a pauper, etc.). I also like what this says about how differences in power shape (corrupt) all social interactions, even when the people in those interactions don’t mean to.

If you don’t buy the Deception rule – when was the last time you were honest with your boss? If you don’t buy the Intimidation rule – how do you feel when a cop pulls you over and starts asking you questions with a hand on his gun?

Passive and Active Perception (The Investigation vs Perception Problem)

D&D, even RAW, has an Investigation and Perception problem. The problem is that they are used inconsistently in the rules text. It isn’t clear what it means to use Investigation as compared to Perception. Both have a passive score on the character sheet. Both are used for searching. Perception is the far more useful of the two, honestly. In most games, there isn’t much reason to take either Insight or Investigation compared to Perception.

For my own games, if you are actively looking for something, I use Investigation, and when we are rolling to see whether you happen to notice something, it’s Perception. Investigation is something like active senses, and Perception is something like passive senses.

I had the idea to clarify this someday with abilities in a game. For active perception, I’d use Attention, and for passive perception, I’d use Sensitivity.

RPG Mechanic Round-Up #7


Progress and Drama

In the game text, instead of listing the result of a passed test in a resolution mechanic as “success”, describe it as “progress.” That is, progress is made toward whatever your goal was, or toward winning what was at stake. In parallel, instead of listing a failed test in your resolution mechanic as “failure”, call it “drama”, in that the dramatic tension increases in the scene or in the story. This could almost be the only change in how a system is written, but I think it opens up results in interesting ways.

Let’s say your D&D player does the classic thing and makes an absurd proficiency check – then they roll a 20, and even though there isn’t a “natural 20” rule in 5E for proficiency checks, they still expect something big from their absurd plan (seduce the dragon, pick the lock with mage hand, lie to the Inevitable’s face, etc.). So if passing the test equals “progress” rather than “success”, you can just describe how their absurd plan gets them closer to their goal. Similarly, for all of those proficiency checks where failure just means the story stops, if it is “drama” (or “tension” perhaps, or “threat”) instead of “failure” for a failed test, the attempt can be technically successful, moving things ahead, but they are now worse than they were.

Theme Music

Each player chooses a theme song for their character and queue’s it up on their phone. At any time during the session, they can hit play for the song, play a bit of it, and their character automatically succeeds on whatever it is they are doing. Maybe instead of Inspiration, players can gain bonus uses of their theme music during the session. Similarly, the DM can queue up theme songs for any Big Bads they’ll face, and those enable them to use a legendary save ability to choose to save on a failed saving throw, or to resist death for a round after being reduced to 0 hit points, etc.

Big and Small Advantages with Percentile Dice

This is a layer of complexity that one might not choose, but it occurred to me while listening (and enjoying) another How We Roll actual play of Call of Cthulhu 7th Edition. In CoC 7E there is an advantage mechanic, where you roll the 10s digit die more than once and take the worse of the two rolls. I thought that this made sense for big advantages and disadvantages, but for smaller advantages and disadvantages it would make sense to roll the 1s digit die twice and take the better or worse of the two rolls. This gives you an approximately 1 in 10 change of barely making, or barely missing, the roll, and isn’t a big deal, but could be an interesting tweak, maybe for when the player thinks they should have advantage but the Keeper disagrees. “Yes, but…”

Percentile Auto-Success

Rolling is not always fun. Games usually have some kind of hand-wavey rule about “only roll when it is interesting” or “only roll when there is danger involved” but even in games where that is spelled out enforcement is sporadic. It occurred to me, in particular in a percentile system, that it could be simpler and also more interesting to give each character a number of auto-successes equal to the tens digit of the applicable skill. So, again looking at Call of Cthulhu, your investigator with a Credit Rating of 57 could just have 5 automatic successes on Credit Rating rolls during the scenario (intended to be more than one session). The downside is that you don’t get any chance to advance when using one of these auto-successes, nor can you get a critical success of any kind. Maybe one could ignore this rule in combat, and of course the Keeper would be able to say that it doesn’t apply in a certain situation (like a Sanity roll, or a situation where the danger of failure is really interesting), but I like it as a rule.

Final Fantasy Action Selector

Remember old school Final Fantasy where you had the action selector when each character’s turn came up? It looked something vaguely like this:

  • Fight / Run
  • Magic
  • Drink
  • Item

I was thinking about something like this for new players. Frequently, players at my table forget all of the various things their character can do when it is their turn, especially at higher levels. What if new players had something like this, printed up by the DM, with their abilities on it? Something for a Druid might look like this:

  • Melee Attack
  • Missile Attack
  • Shapechange

And one for a Rogue more like this:

  • Melee Attack
  • Missile Attack
  • Dash
  • Disengage
  • Hide

Of course, the player can put whatever is interesting on the selector, and can always do things not listed, but it might be helpful to just have that at a glance. I’ve seen a lot of new players stare glassy-eyed at their complex character sheet when their turn comes when really they only have two or three viable and interesting options. The problem is that it takes significant system mastery for one to know what those few viable and interesting options are.


Ken Hite, Tim Powers, and the Great Old One Himself

Image: Bruce Timm’s rendition of Lovecraft, c/o Dark Forces Book Group

I was having a conversation with a friend and colleague today about a number of things, among them Tim Powers and H. P. Lovecraft. Feel free to check out more about both of these authors if you’re interested via Wikipedia. Whoever is reading this blog probably knows who Lovecraft is and may or may not know who Tim Powers is (he’s an award-winning fantasy author who focuses on secret histories).

I was reflecting on a quote from Lovecraft, and something occurred to me – the fact that along one axis at least, Powers and Lovecraft are mirror images of each other. The Lovecraft quote is this:

The most merciful thing in the world, I think, is the inability of the human mind to correlate all its contents. This quote is the first line from Lovecraft’s most famous tale, The Call of Cthulhu. What Lovecraft seems to be alluding to here, as well as in other works, is that if one were to understand the totality of existence, one would fall into madness and despair, and that our inability to fully comprehend is our salvation as a species. As long as we are in the dark, we are ok. When the truth is revealed to us, it shatters us.

I compared this to Tim Powers. What Tim Powers is good at is writing fantasy that takes place in the lives of known, historical figures and events. He takes the supernatural and intersperses it into history almost seamlessly, so that you come away from the story thinking “For all I know, that’s how it went.” He does this by doing a tremendous amount of research both on the ‘official’ history of people like Romantic poets or famous pirates or Cold Warriors and then finds the spaces between what is recorded them and inserts the fantastic.

What Tim Powers does, in other words, is he skillfully correlates the contents of his mind. Because he is able to do this, he is able to put together truly amazing stories that do not have to shatter our accepted history, but only embellish it, like a virtuoso soloist in a jazz ensemble. The soloist isn’t breaking the music, s/he’s making it even more beautiful and evocative.

Where Lovecraft saw horror and insanity, Powers sees beauty and stories worth telling, and both of them take their jumping-off place, in part, from correlation. Lovecraft looks at the immensity of experience and thinks “Behind all this is some kind of seething, infinite darkness which means us ill.” Powers looks at the same immensity and complexity and interconnectedness and thinks “I bet I can tell a story about Lord Byron the vampire hunter, or the Cold War fought by means of genies, or Texas Hold ’em players fighting for control of a Tarot-throne in Las Vegas.”

In the final analysis, while Lovecraft has had a far greater impact on our culture than Powers, I prefer Powers’ view. It is another kind of genius. Rather than fear, Powers tends to offer wonder. Both writers are awe-ful in their own way, however, and very much worth reading.


I only mentioned Ken Hite in this post because he is the author of many superb books on the Lovecraft Mythos, the most recent of which is Cthulhu 101. Look for it wherever games or comics are sold.