Call of Cthulhu

Call of Cthulhu
RPG published by Chaosium
Rule System	Basic Roleplaying System
Authors	Sandy Petersen
First Publication	1981

Call of Cthulhu is a roleplaying game based on the writings of H.P. Lovecraft, in which the player characters are more or less normal guys who might be able to fire a pistol without killing themselves. They try to find the truth of all existence. In the course of their investigations, the players might find themselves fighting horrors from beyond space, such as Cthulhu, who eats 1d3 investigators per round and is generally cranky after being woken from millennia of slumber.

System

Call of Cthulhu uses the Basic Roleplaying System (BRP), first used in Runequest and also for Stormbringer, Elfquest, and a variety of other games. It uses an array of D&D-style attributes (STR, DEX, INT, CON, POW, EDU, APP, SIZ) rated on the familiar 3-18 scale (since 7ed those are on %-scale), plus around 60 skills rated as percentiles.

Basics

To perform any action, roll d100 and try to get under your skill; rolling 1/5 of your skill is a critical success, or an 'impale' on an attack. Used skills are marked and at the end of the adventure may increase by 1-3 points if you succeed in rolling under the inverse of the skill. This leads to very gradual and organic character progression, and encourages players to use as many of their skills as possible at least once per adventure. Attributes are checked in exactly the same way, though are typically multiplied to make the check passable, typically by 5. Another option is comparing them to an opposing score on a resistance table, for every point of difference the check is 5 points easier or harder, and 10 points difference is either an automatic success or failure (for example, someone with 10 STR trying to bust a door in with 12 STR has a 40% chance of doing so). Damage is handled via hit points, which for PCs never advance beyond the region of 10-20, though if they can justify it to the keeper they can get armor.

Character Generation

Chargen is a relatively long process due to the number of skills and the percentile values, although the free program Byakhee is available to speed things up. You roll attributes, select a profession, gain a bunch of skill points to spend on your professional skills, (such as archeology or painting) then a bunch more to spend on your hobbies. For instance, firing Tommy-guns (which definitely ISN'T a total waste of points).

Gameplay

Investigators are typically unable to go toe-to-toe with the monsters in CoC, so most of the game consists of investigation, exploration and gathering clues, with the investigators typically finding something they can do to either destroy or banish the thing that has been ravaging the area. Imagine Scooby-Doo, except with eldritch, inter-dimensional horrors that will almost certainly kill you or drive you mad (so basically imagine the Scooby-Doo Mystery Incorporated finale), and who are impervious to most weapons humans can muster outside of a goddamn Howitzer (or a passenger ship, or everyone with a boomerang) to deal with (though, shotguns should work for anything roughly man-shaped), rather than Old Man Withers dressed up as a ghost to scare away the locals.

If you are lucky your investigations will allow you to reach any sort of confrontation armed with magic (which, you guessed it, drives you insane to use), a list of the creature's weaknesses, or at least a metric fuckton of dynamite. Spot Hidden and Library Use are two of the most commonly used skills and any player that thinks a gun is useful for anything other than intimidation will be having a fun time swimming inside a Shoggoth or using it on themselves to stop the voices.

One thing of note is the difference between pulp and purist play, each one supported by different rulesets as of 7th Edition. Purist is Call of Cthulhu "as God intended"; where investigative mystery comes first, witnesses and research are your main weapons and the real thrill comes from the intrigue and the sheer threat. Pulp is Call of Cthulhu as the Lovecraft-Lite action-adventure game, where the Mythos can be pushed back with judicious use of firepower and dynamite and humanity can prevail against the encroaching dark... at least for a time. Pulp stories tend to be more internationalist as opposed to being in one geographic location primarily, and the timeline is brought forward a bit to the Dirty Thirties - the Great Depression is in full swing, liberal democracy is under threat from a sweeping tide of authoritarianism, most Americans are dirt poor and/or unemployed, quick and cheap intercontinental air travel is now a thing, and movies no longer suck. Characters in pulp games have more HP and become quite a bit more likely to survive, but it arguably loses some of the horror and imminent danger that comes from purist play. There are merits to both styles so give 'em both a try!

Sanity

Sanity or SAN represents your mental stability. It is capped at the inverse of your Cthulhu Mythos skill; that is to say, you cannot know what is really going on and remain sane. When you experience something terrifying you make a SAN check; if you fail you lose a random amount of SAN, and often a small amount if you succeed as well. If you lose a substantial amount (five or more in one go) you can have a panic attack, flee or any other sort of madness, though you have to roll to repress the memory of the thing you see first. If you lose a very large amount (one fifth in a game hour) you can develop phobias, mental conditions, or go insane for months on end. If you run out entirely you become an NPC, who may go insane and gibber in a corner for the rest of his life, or he may go and join the bad guys. It's not all bad though, as going insane from something mythos-related actually gives you insight into the thing you have seen.

Sanity loss is a source of both frustration and good roleplaying opportunities, as on the one hand playing out multiple personality disorder can be good fun. On the other hand being trapped in a hole with a monster is bad when one character has a darkness phobia and is curled up in the fetal position, one is claustrophobic and has fainted and one with a snake phobia who refuses to use the rope to climb out can be either frustrating or Fun for player and keeper alike.

Setting

CoC is set in the world of Lovecraft's Cthulhu Mythos but incorporates many of the inventions of later writers and the revisions of August Derleth. The historical setting is the 1920s, the era when Lovecraft wrote most of his work. However you have a plethora of other historical settings to choose from, so you can be jumping through time more than your average season of Doctor Who. Modern day adventures (specifically the 1990s, though nowadays even that decade is starting to veer into period piece territory, oof) are also possible and have had a healthy amount of official support over the years - traditionally sold as a side setting called "Cthulhu Now", but as of 7th Edition the modern setting is folded into the core rulebook so you can run modern adventures right away. However, while the modern day has the obvious advantage of being more relatable to the players, the Jazz/Classic era has several other advantages:

• The lack of readily available communications (no cellphones or internet for you!) makes it easier to isolate the investigators from outside help,
• The fact that parts of the world like the Amazon and the Himalayas were still unexplored,
• World War I was only a few years ago, which means any adult male in their twenties or thirties will plausibly have military experience and be confident in a scrap.

All in all, the 1920s was just more mysterious; it is harder to run games in modern eras because players will have all kinds of nifty technology to derail the adventure or circumvent the threat.

It should be noted of course that you shouldn't allow yourself to get worked up over historical accuracy, and feel free to take all kinds of liberties with events. Treat it like magic - "it's Lovecraftian horror, I don't need to explain it".

Some of the other more well-known historical settings are:

• Cthulhu Invictus: Set in the Antonine period (96AD - 180AD) of the Roman empire. The empire is (relatively) stable and the citizens are (mostly) content. Sounds great right? Except there's a shadow war going on where agents are running around the empire fighting the Mythos wherever it rears its ugly head. Inhuman races and fantastic and terrible creatures still have a strong presence in the world in times before modernity forced them underground, and all kinds of unspeakable cults lurk in everyday society. Roman society was extremely different from today; you live under a vast multinational military dictatorship built on centuries of slaughter and slavery, that controlled their citizens in ways that would make modern fascists blush. People tend to do things more for honour or personal glory than because it's right, and nobody will think you are crazy if you tell them you saw a satyr or that someone cast a spell on you (in fact some careers actually start with a spell or two). This is a setting that fits pulp or purist rules equally well, recently got a 7th Edition book, and definitely one you should at least give a try.
• Cthulhu Dark Ages: And just as you were starting to get used to Rome, it collapsed! The empire fell and Europe is now a patchwork quilt of squabbling barbarian kingdoms. But the Mythos is still out there, and it represents as grave a threat as it always did. The world is built on the ruins of ancient civilisations, not just Rome but Stygia, Hyperborea and Atlantis as well. Here, the horror comes not from the Mythos threatening humanity's (at this time lacking) understanding of the world, but its religious bedrock - you should strive to shake the faith of your PCs to their core and make them doubt their God even exists! And the medieval weapons and armour technology makes combat encounters especially lethal. Just recently received the 7th Edition treatment from Chaosium. Included in the book is details of an Anglo-Saxon community and a bestiary to throw at it.
• Mythic Iceland: It's the Cthulhu Mythos versus the Vikings. Nuff said. At a whopping 276 pages, it's less a campaign setting and more a mammoth almanac containing character creation rules, a special bestiary for Icelandic creatures, a full adventure, almost anything you would need to know about Icelander life (their religion, lifestyle, unique legal system and government, etc.), a new runic magic system, information about other lands, and even a supplement for Dark Ages and an adventure for that too! Brilliant, brilliant book. Grab it.
• Reign of Terror: Mon Dieu, it is ze French Revolution, the birthplace of modern democracy; a time of mass bloodshed, intrigue and social upheaval. In other words, the perfect setting for battles with the Mythos. More a pair of scenarios expanding on the campaign "Horror on the Orient Express" than a complete setting but it gives enough flavour and options for further expanding it into it's own thing, plus plot hooks for Keepers to expand on.
• Down Darker Trails: Strap on your six shooters and saddle up, cowboy, because you're taking on the Mythos in the days of the old American Wild West. Expansive book with lots of historical details and options to play entire campaigns in. Comes with both regular and "Pulp" rules to fit all tastes (and the increased focus on gunplay will probably see you going the Pulp route) and has at least one campaign book as of writing. Definitely worth a look.
• Cthulhu by Gaslight: Lovecraftian horror set in the Gay 90's, the 1890s that is! This is Cthulhu adventures in Victorian Britain, specifically - the zenith of the British empire, the time of Sherlock Holmes, Jack the Ripper and Penny Dreadful. It's very similar to the Jazz/Classic 1920's but with some key cultural differences, namely England's vast history (remember the saying, "in America a hundred years is a long time, in England a hundred miles is a long way" - isolation is going to be more of a problem, but you can take advantage of conspiracies and events going back to medieval or even pagan times), gross social inequality and class warfare, widespread interest in occult matters, less access to technology (no cars, telephones or repeating firearms here!) and lots and lots of fog. Enjoy!
• Pulp Cthulhu: This variation moves the setting forward to the pre-war 1930's (to accomodate air travel and globe-trotting adventures) and changes the tone of the game to two-fisted pulp flicks, like Hugo Gernsback's Amazing Stories. PCs in Pulp Cthulhu will be somewhat more capable in a scrap than usual and have access to gunplay, psychic powers, combat feats and weird science, perfect for punching out Nazis and dinosaurs and whatever else you end up against. There is even a mechanic for spending Luck points to bring a dead character back to life, suitably with a ridiculous story of how they "really" survived the circumstances of their death. Keep in mind though that Pulp characters can still lose SAN and go batshit like usual, and those extra HP can only take you so far.
• Achtung Cthulhu: It's World War II, but with the Mythos. Currently in limbo as the company making it, Modiphius, released a 7th edition PDF and were talking about their own rules version of the game but have gone quiet. Think commandos and OSS operations against Nazis who are probably being their usual twat selves and playing around with Mythos bullshit to give them an edge over the Allies. Has the advantage of having two major antagonists to blow away in a hail of bullets and tank fire. Definitely better used with pulp rules, as otherwise your PCs will probably be killed in a hail of gunfire before you can say "Oh shit, I forgot Nazis tend to have MP40s."
  • As an alternative there is also World War Cthulhu by British developer Cubicle 7, which focuses on World War II and covers a bit of the first decade of the the Cold War too.

There are also these much less used settings:

• Convicts & Cthulhu: G'day, mate! You lot are heading to Australia!... As in Australia, the 1800s penal colony. It's literally on the other side of the world from the "civilised" world, claustrophobic and remote, so it is a great setting for horror. Aboriginals, criminals and goalers who are not so different from the crims come together in the embrace of madness.
• Dreamlands: Beyond the veil of sleep lies an ethereal and haunting alternate dimension which resembles a more fantastical version of Earth's past, where the gods themselves play and all kinds of bizarre alien races and civilisations live. Maybe you came here by descending down the Seventy Steps of Light Slumber, maybe you saw the White Ship and decided to hop on and see where it takes you, or maybe you entered through one of the many gateways in the waking world, like the one in Germany's Black Forest, the California redwoods, or Roanoke Island. Whatever the case, welcome to the Dreamlands, Lovecraft's foray into Alice in Wonderland-style fantasy, and it can be your foray too! It is a world of incredible wonder and danger in equal measure, and death in the Dreamlands induces dream death, causing you to go insane or die in your sleep. What fun!
• Cthulhu End Times: End Times is a post-apocalyptic horror setting in the 22nd Century. The stars finally came right, the Great Old Ones returned and the world screamed when they did. Most of humanity died immediately in the madness or the atomic fire (they were the lucky ones), and the few left are mostly enslaved by the alien gods or wandering deranged, but a few live in isolated primitive states and fewer still exist as small warbands taking the fight to the cults wherever and whenever they can. The only free and sane humans left are on two tiny colonies on Mars, numbering about 1000, and with no contact with Earth (as anybody who just looks at it through a telescope loses their minds). One thing of note is the End Times: The Reaping setting in Through The Ages (described below) is deliberately vague on the lore, allowing post-apocalyptic adventures can be set in the modern day, the future or even the past (say the investigators of 1927 failed to stop R'lyeh from rising from the ocean floor and the world failed its collective SAN roll when a psionic alien god reached out and crushed the minds of every person in the western hemisphere). You can even go against the intended use and run zombie apocalypse games in End Times completely independent of the Mythos, the lethal combat lends itself very well there.
• CthulhuTech: For when regular Lovecraftian horror no longer cuts the mustard. This is a heady cocktail of Lovecraftian horror, cyberpunk sci-fi and space opera, with a dash of Shadowrun, Neon Genesis Evangelion and Macross for flavour. Set in 2085 AD, this setting adds rules for cybernetics, virtual reality, psionics, superhuman abilities, directed energy weapons, and motherfucking robots. But even with all their cool toys, humanity is fighting a losing war against the Mythos and everyone on some level knows they're doomed, so most people live in denial, use drugs to escape or hold their weapons fast and fight to the bitter end. It's Awesome.
• Cthulhu Sverige: Very new setting book, fresh from Kickstarter, centred on adventures in Sweden in the 1920s. Currently only available in Swedish and no current plans for an English translation, but might still be of interest for collector's value.

I would highly recommend you pick up the Cthulhu Through The Ages book which acts as a delicious smorgasbord for many of these settings. Weighing in at a lightweight 81 pages, it contains barebones rules for Invictus, Dark Ages, Mythic Iceland, Gaslight, Dreamlands, End Times and Icarus (claustrophobic survival horror set on a spaceship, think Alien or Event Horizon), as well as investigator occupations and organisations, idea seeds for adventures, and period equipment lists (plasma weapons for the futuristic settings and medieval weapons and armour for the pre-gunpowder settings... and the post-apocalyptic one too, for that matter).

The premise of Lovecraft's world is that we live in a small circle of firelight and sanity created by human civilization, and beyond that circle the universe is dark, uncaring, and full of things with tentacles and too many eyes. There is no God, all our religion and spirituality is just a fake comfort blanket, and our science doesn't properly describe the universe either. We are unimportant but also unfortunately we are not alone; there are many aliens that inhabit our reality and the parallel dimensions we cannot (usually) perceive, and when we do perceive them, it usually ends badly. These aliens aren't like Star Trek or Warhammer 40000 baddies where we can reason with them or simply remove them with force if we can't. They are more like demons or gods - ancient beyond reckoning and able to manipulate time, matter and space with ease. We also cannot comprehend their intelligence or their technology, and communication between us and them is only on a crude level (often using their psychic powers to influence our dreams). The prevailing theory is that our species was created 300,000 years ago by an elder race who ruled Earth in the time of the dinosaurs, then they either left to go fight a war with one of their other creations gone rogue, or they just created us as amusing fools and then forgot all about us when the novelty of the joke wore off. Problem is, they probably haven't forgot us, and they want their planet back. Even their lowly servants are often beyond our ability to defeat, and the best we can manage is temporary victories that push the doomsday clock back a decade or two and allow us to carry on just a little longer. But we will fail, eventually.

In terms of physical location, the (fortunately) fictional city of Arkham, Massachusetts is a common setting. Arkham is an amalgamation of several New England towns and contains all the massive libraries, decaying colonial houses, faux-gothic estates and inbred lunatics that one could want for an American horror setting. There is also Arkham's Miskatonic University, an organization with a worse safety record than the fucking Umbrella Corporation. If your character is a professor, he likely teaches at Miskatonic, and will therefore surely die.

CoC on /tg/

This joke is older than most of you assholes reading this page.

Call of Cthulhu is consistently popular among gamers. "Roll for SAN loss" has inevitably become a meme, used in place of "ARGH, MY EYES" or sometimes "MAN THE HARPOONS".

See Also

• Trail of Cthulhu, an updated version of the game using the GUMSHOE system.
• Delta Green, a modern-day campaign setting for the game, in which the player characters are various military or government employees. Think X-Files with a dash of SCP Foundation and you have a good idea.
• Old Man Henderson, the only man crazy enough to ever defeat the Great Old Ones at their own game.
• Gunslinger Rick, he shot Cthulhu back to R'lyeh. Then left to smoke a cigar. He didn't win, not on the scale of Old Man Henderson, but he did give humanity another couple of million years

External Links

• Byakhee Character Generator (Sourceforge)
• Dhole's House Character Generator includes useful tools like handout generator and supports Pulp Cthulhu
• Chaosium Inc, publishers of Call of Cthulhu
• Basic Rules
• Basic Roleplaying, the system it's based on
• Chaosium's page

Published Editions

• 

  First Edition

• 

  Second Edition

• 

  GW Third Edition

• 

  Fourth Edition

• 

  Fifth Edition

• 

  5.5-5.6 Edition

• 

  Seventh Edition

• 

  D20 Edition

• 

  Japanese D20 Edition