Call of Cthulhu, 1st Edition

“Fantasy Role-Playing in the Worlds of H.P. Lovecraft”

Copyright 1981, Chaosium

Author: Sandy Petersen
Co-Authors: William James Hamblin III, Steve Perrin, Greg Stafford, Anders Swenson, Lynn Willis.
Illustrations: Gene Day

Box cover

Box back


Physical Components:

Rulebook (96-pages, 8 1/2" x 11")
A Sourcebook For the 1920's ( 32-page 8 1/2" x 11" )
Call of Cthulhu Worldmap (22" x 34")
Box (9 1/4" x 12 1/4" x 1")

The Museum's copy is incomplete. The box originally also held the Basic Roleplaying Rules book, dice, a sheet of paper characters to cut out and stand up, and a character sheet.

Supporting products in the collection:

Rules and sourcebooks

Call of Cthulhu, 2nd edition. Sandy Petersen. Chaosium, 1983. Copy donated to the Museum by Louis La Mancusa.

Call of Cthulhu, Edition 5.2, Sandy Peterson & Lynn Willis. Chaosium, 1995.

Keeper's Compendium: Blasphemous Knowledge & Forbidden Secrets. Keith Herber, with Aniolowski, Ross, Clark, Jeffrey, Szachnowski, Geier. Chaosium, 1993

1990's Handbook. Gregory Rucka, with Earl Geier, Drashi Khendup, Kirk Wescom. Chaosium, 1995.

The Complete Dreamlands, 4th Edition. Chris Williams, Sandy Peterson, with Appel, Campbell, J. Clegg, S. Clegg, Frances, Herber, Hutchinson, Willis, Bayless, Carrick, Eckhardt, Gallachi, Geier, Ramos, Roland, Schultz-Savoy. Chaosium, 1997.

Delta Green. Dennis Detwiller, Adam Scott Glancy, John Tynes. Pagan Publishing, 1996.

Delta Green: Eyes Only Volume One Machinations of the Mi-Go. Dennis Detwiller, Pagan Publishing, 1998.

Delta Green Eyes Only Volume Two The Fate. Dennis Detwiller, Pagan Publishing, 1998.

Delta Green: Countdown. Dennis Detwiller, Adam Scott Glancy, John Tynes. Pagan Publishing, 1999.

Malleus Monstrorum: Creatures, Gods, & Forbidden Knowledge. Scott David Aniolowsky with Sandy Peterson & Lynn Willis. Chaosium, Inc., 2006.


The Unspeakable Oath, Issue 13. Pagan Publishing, 1995.

Keeper's Screen. Chaosium, 2010.


Adventures and campaigns

At Your Door, L.N. Isynwill, Herbert Hike, Mark Morrison, Barbara Manui, Chris Adams, Scott D. Aniolowski, Lee Gibbons, Earl Geier. Chaosium, 1990.

Fearful Passages. M. Anderson, P. Anderson, Bjørksten, Gillan, Hatherley, Jeffery, Kluskens, Love, Morrison, Routt, Rowland, Smith, Willis. Chaosium, 1992.

The Walker in the Wastes. John H. Crowe III. Pagan Publishing, 1994.

The Complete Masks of Nyarlathotep. Larry DiTillio, Lynn Willis, with Shannon Appel, Mike Blum, Jason Eckhardt, Lee Gibbons, Geoff Gillan, Penelope Love, Michael McDonald, Sandy Peterson, Thomas W. Phinney, Kevin A. Ross, Mark Schumann, Nick Smith, and Tom Sullivan. Chaosium, 1996.

The Compact Trail of Tsathoggua. Keith Herber. Chaosium, 1997

A Resection of Time: The Strange Case of Kyle Woodson. Sam Johnson, with Scott Baxa, Paul Carrick, Drashi Khendup. Chaosium, 1997.

Escape from Innsmouth, 2nd Edition. Kevin Ross, with Aniolowski, Behrendt, Herber, Kingrea, Morrison, and Szymanski. Chaosium, 1997.

The Realm of Shadows. John H. Crowe, III. Pagan Publishing, 1997.

No Man's Land: WWI Mythos Action with the Lost Battalion. Sam Johnson. Chaosium, 1998.

Before the Fall: Innsmouth Adventures Prior to the Great Raid of 1928. Ralph Dula, Michael Lay, Gary O'Connell, Gary Sumpter, Lucya Sazchnowski, Tom Sullivan, M. Wayne Miller & Dreshi Khendup. Chaosium, 1998.

Beyond the Mountains of Madness: An Epic Antarctic Campaign & Sourcebook. Charles and Janyce Engan, with Michael Blum, John Goodrich, Mike Lay, and friends. John T. Snyder. Paul Carrick, and M. Wayne Miller. Chaosium, 1999.

H.P. Lovecraft's Arkham. Keith Herber, Mark Morrison, Richard Watts, & Mervyn Boyd. Chaosium, 2003.

Ripples from Carcosa. Oscar Rios. Chaosium Monograph, 2005.

Tatters of the King. Tim Wiseman. Chaosium, 2006.

Arkham Now: Revisiting the Legend-Haunted City . Brian Courtemanche and Matt Sanborn.. Chaosium, 2009.

Age of Cthulhu: Shadows of Leningrad. Mike Ferguson, Goodman Games, 2010.

Age of Cthulhu: Horrors from Yuggoth. Adrian Pommier, Goodman Games, 2010.

Back to the Horror Wing
Back to the main lobby

The year is 1923. A small band of antiquarians, historians, and dilettantes slowly uncover the awful truth: the safe, understandable universe gradually being uncovered by rational science is really only a tiny fragment of a much larger reality that has no place for humans. Worse, reality is filled with gods and godly beings known to no sane religion. These beings have no concern for humanity at all, except perhaps as an occasional snack. The universe is cold, empty, and meaningless. The few who discover this reality either go mad or are eliminated in horrible nameless ways. What's more, a few demented souls are in touch with this reality, striving to bring their horrible masters to Earth. It is inevitable that these beings will take over the Earth "when the stars are right." All is hopeless despair.

Sound like fun? Oddly enough, this is the setting of Call of Cthulhu. Undoubtably one of the great classic role playing games, CoC (as it is abbreviated) is still going strong after twenty two years. It has evolved over time, but the basic game mechanisms remain the same, a tribute to the strength and flexibility of Chaosium's Basic Role Playing (BRP) game engine.

In fact, the preservation of the basic game mechanisms is what makes this review possible: our copy of the first edition of CoC is incomplete, lacking the BRP rulebook among other items. But the 2nd edition rules allow us to fill in many of the gaps.


The Setting

Many gamers are familiar with the works of H.P. Lovecraft (1890 - 1937). Lovecraft wrote a series of horror stories revolving around the concept of the Great Old Ones, terrible beings and gods to whom humanity was either beneath notice or served as prey. Lovecraft's themes include the ideas that the more we probe into the mysteries of the universe, the more we will discover that the universe is at best indifferent to us, and probably hostile; that our minds will not be able to cope with the truths outside of our comfortable corner of space; and that there are higher orders of beings to whom humans are irrelevant. The stories involve powerful gods and beings with unpronounceable names, ancient books that drive their readers mad, crazed and depraved cultists seeking to let the Great Old Ones loose upon us, and clueless protagonists that stumble upon all of this, whose knowledge marks them for madness and death. In short, an ideal background for role playing.

Lovecraft's creation tempted others to contribute, and his friends added more creatures, gods, and insane books. The whole construction became known as the Cthulhu Mythos, named after Lovecraft's Great Old One, Cthulhu, who lies "not dead, but dreaming" at the bottom of the Pacific Ocean in his dead city of R'lyeh. Nearly eighty years after Lovecraft's death, the Cthulhu Mythos is still being churned with new stories for avid readers.

Since virtually all of the protagonists in the stories who discover the Mythos go insane or die, the game must likewise assume player characters ultimately fail. While the enemy can be set back, there can be no real victory. Having one's character foredoomed can lead to fascinating role playing, completely opposite from the traditional heroic fantasy mode. Characters in CoC investigate mysterious goings on, but must take care because they rarely have the strength to take on their opponents directly—in fact, even seeing some of their opponents will drive the player characters mad! CoC players must be subtle and crafty to defeat their crazed opponents' plans to remake the world in blood and madness.

Central to this concept is the Sanity characteristic. Player characters begin with a sanity score, and this is steadily eroded during play. As sanity drops, characters sometimes gain insight into the Mythos, the truth underlying the universe. (The higher one's Mythos score, the lower one's sanity must be.) Eventually the character is driven completely insane, and is retired from the game.


The Game

Call of Cthulhu was based on the logical and effective Basic Role Playing rules, themselves evolved from Runequest. BRP removed some of Runequest's chrome, while retaining the strengths of the system. Ultimately, however, CoC was never about rules: it was about the setting. Any referee or player who had read a few of the Cthulhu Mythos books was ready to begin playing. The main task of the game was to translate the books into game statistics, and to provide materials for players to recreate the world of the 1920's. In case players did not know about Lovecraft, the rules provided a list of some key stories, and recommended players and Keepers (CoC's term for the referee) read at least some of them.

As noted above, our copy is missing the Basic Role Playing rules booklet. This would contain the basic rules on character generation, combat, and using experience to improve a character's skills. Luckily, the second edition rules are complete. There are three core mechanics: roll below one's skill with percentile dice to succeed; roll against a multiplied characteristic to succeed (usually a characteristic times five, to turn the 3 - 18 characteristic into a 15 - 90% chance of success); and compare your characteristic to an opponent's on the Resistance Table to determine a percent chance of success, then roll percentile dice. To improve skills, players note on their character sheet each time they successfully use a skill, and at the end of the adventure, and if they roll higher than the current value of the skill on percentile dice, the skill improves by 1d6 points.

Because Call of Cthulhu is not set in a typical fantasy universe, some adjustments needed to be made to BRP, and these are found in the main rule book. This book consists of rules to modify character generation, including a new skill list; rules on sanity, a quick description of the universe of the Mythos, descriptions and game statistics for many of the beings of the Mythos, rules on how magic works in the game, a list of spells, and three pages of advice on how to run the game. The book also includes three scenarios, a map of the city of Arkham, and some fascinating appendices: some scholarly notes on the dread Necronomicon; notes on cultists, their behavior, and what monetary treasures are likely to be found if they are defeated in their lair; some notes on libraries, along with a list of libraries known to hold occult materials of value to Investigators; and some scenario fragments to help beginning referees along.

Character Generation

Call of Cthulhu characters, or Investigators, are mainly generated as described in the (missing) BRP book, with only two modifications. Players roll 3d6 each and record the totals for Strength, Constitution, Dexterity, Appearance, and Power. Players roll 2d6+6 for Intelligence and Size. One of the modifications is the need for an Education score, generated by a roll of 3d6+3, with each point roughly equal to a year of schooling. The second is the Sanity score, which is calculated as Power times five. As in other BRP games, no modifications of scores is permitted at character generation. Hit points are the average of one's Constitution and Size statistics.

Players then choose an occupation for their character. This will influence what skills the player knows at the start of the game. Choices permitted here are journalist, parapsychologist, professor, historian/antiquarian, author, private investigator, or dilettante. Players may also negotiate with the Keeper if they desire other occupations. Players get education (EDU) times ten points to spend on skills from the occupation's short skills list. After spending these points, the player may have intelligence (INT) times five points to buy any skills allowed in the game, all neatly listed on the one-page character sheet.


True to the heritage of BRP, CoC has a moderately detailed combat system, one hardly necessary for a game where the focus is on investigation instead of combat. Simply put, characters attack in order of their dexterity, from high to low. A player tries to roll below her skill score for a particular weapon on d100, and if successful, damage is determined by rolling the appropriate damage dice for the weapon. All characters and creatures also get a damage bonus added to this, based on their strength and size, if they are large and/or strong enough. Damage is subtracted from the defender's hit points total. Armor (and few Investigators will have any), subtracts from the damage done. Instead of critical hits, a particularly successful hit (a roll of less than one-fifth of the character's skill score) is an "impale." An impale means rolling for damage, adding the maximum damage possible for that kind of attack (so damage can be up to double), and the weapon remains stuck in the victim until attacker or victim pulls it free. Not all weapons can impale.

Firearm combat uses the same mechanics as for melee combat, with minor differences. Guns usually permit multiple attacks, with the first shot happening before any melee attacks are permitted. Guns are also ranged weapons, but they can be used at point-blank range, doubling the attacker's chance of success. Bullets may impale, doing additional damage. The disadvantage to guns is that they take time to reload, and automatic weapons have a small chance to jam.

Combat is much simplified from the parent game Runequest. Strike Rank is no longer calculated (Runequest measured who went when in combat by a function of dexterity, size, surprise, and weapon length), the hit location system has been removed, armor is rarely a consideration, parrying has been greatly simplified, and critical hits and fumbles appear to have been removed. As a result, combat goes much more quickly in CoC. Since many Investigators and their foes can be expected to have guns, combat tends to be faster and deadlier. Unlike most fantasy role playing games, one does not enter combat in CoC casually.


As mentioned above, the sanity mechanic is one of CoC's best-known innovations. Calculated at character generation as the character's Power times five, the player must roll their sanity or less on percentile dice whenever they confront the horrors of the Mythos, or when they face other strong psychological shocks, such as seeing a mutilated corpse. Failure means the loss of sanity points, the exact amount depending on the kind of shock the character receives. Even a successful sanity roll usuallly means the loss of one point. If a character loses five or more sanity points at once, he goes temporarily insane. The referee rolls for a random insanity on a table. The authors wisely limit the options to common literary insanities—catatonia, amnesia, stupefaction, paranoia, or a wide variety of phobias—rather than trying to duplicate authentic psychological disorders. For temporary insanity, this lasts for a random period of time and the character will recover without assistance. If the character loses 20% or more of her sanity in an hour's time, she is "permanently insane." Keepers are encouraged to select an appropriate infirmity based on the stress the character has undergone.

Permanent insanity is perhaps a misnomer, as it can be cured via psychoanalysis. Characters in therapy commonly recover one point of sanity for each week of therapy. Characters may also be institutionalized, where they roll for a cure every 1 - 6 months. Notice that an institutional cure does not boost sanity points, only cures the insanity. Sanity points can be recovered without psychoanalysis, although this is something of an in-game reward, with the points being granted as a result of defeating opponents. Sanity may also be gained by improving a skill to 90%, a result of the boost in self confidence from becoming an expert.

When a character's sanity reaches zero, they are incurably insane, and no longer available as player-characters.


Magic in the universe of CoC is probably better left to villains. It erodes sanity to learn and use it, and the spells detailed in the rules are mainly for summoning monsters of the Mythos, although knowledge of the spells can sometimes be used to dismiss Mythos fiends. No characters begin the game as spell-casters; spells are commonly learned in play through the discovery of obscure and horrifying books. Mythos books are noted in terms of the language they are written in (not always English!), the amount they add to a character's knowledge of the Mythos skill, how much sanity is lost by reading them, and a "spell multiplier," which players multiply their character's intelligence score by to find the probability of learning a spell from the book. Keepers decide in advance how many spells can be found in the book, and in what order they are learned.

Should a character learn a spell and wish to cast it, they will always pay in sanity and power points to do so. Some spells also require physical adjuncts, such as blood, an enchanted whistle, or even a field of nine boulders or menhirs arranged in a V pattern. The spell list is brief and simplistic, nearly all dedicated to contacting the beings of the Mythos. They are broadly classified into Summon spells (used to call up the minor extradimensional servants of the Mythos gods), Binding spells used on the same, Contact spells (used to get in touch with the servant races found on or below Earth), Call spells (used to summon and dismiss the Mythos deities), and Contact spells (used to speak with the Mythos deities, usually without summoning them bodily). There is a small grab-bag of additional spells. There are only two combat spells in the game that might be used against mortal opponents, and one spell that can be used to bar an opening or path against the beings of the Mythos, much as a crucifix is said to repel vampires.


These rules, plus information about the creatures and beings of the Mythos, takes sixty-nine pages of the rulebook. Five more pages are used to give guidance to Keepers in how to structure adventures and run a campaign. Three short, ready to play scenarios are included ("The Haunted House," "The Madman," "The Brockford House"), which the rulebook says are best used as a models for how to construct a scenario rather than run as-is. There are ten pages of appendices, some of which are background material (a supposed scholar of Arabic describes the derivation of various terms from the Necronomicon; a list of libraries containing significant occult tomes), some of which are useful for Keepers (monetary reward for successful Investigators; notes on cultist groups and how they worship; sages; scenario seeds; skills for sailing, boating, and shiphandling), and a few historical notes: a very brief timeline for H.P. Lovecraft's life, and a map of major rail and steamship lines in New England. The game closes with a short catalog of books sold by Arkham House, publisher of Lovecraftian fiction, and the inside back cover has errata and additions to the rules dated October 1982. (Our copy is a second printing of the first edition.)


The Sourcebook for the 1920s included in the boxed set is rather brief, at 31 pages, but has some very useful information. It can be divided into history (timelines, including natural disasters and Fortean paranormal incidents; thumbnail biographies of period celebrities and others who will become famous later; notes on gangsters and prohibition), material directly useful for Keepers (price lists; information on travelling in the 1920's including how long travel usually takes, and how much tickets cost for rail, ship, and air; notes on law enforcement; diagrams of rail cars and a dirigible), additional goodies for Basic Role Playing (a short list of animal and traditional monster stats; weapons, such as machine guns and farm implements), and some diagrams of famous archaeological sites (such as Nan Madol in Ponape; Scara Brae in Orkney; Teotihuacán in Mexico). There is an alternate character generation system, more detailed than the one in the main rulebook. This system builds a character up through her past experience, so that they are more detailed and their skills are more directly related to this character's specific life history. Most interestingly, there is a chart that breaks the world up into eleven zones, with a brief table for each zone that shows what typical weapons NPCs in that zone would be armed with.


Call of Cthulhu was a revolutionary game. It was one of the first based on an outside, licensed property. It pioneered the idea that a role playing game was about telling a story, not just hacking up a random assortment of monsters. We quote from the rulebook, page 72: "Charts for random encounters ... are the bane of Call of Cthulhu. In this game, each adventure should be carefully crafted to give the players the maximum amount of thrills and chills." While the first edition needed better organization, it is instructive to look at some of the changes between the first and fifth edition to see how little needed to be adjusted to keep the game fresh.


Changes in the fifth edition

Most immediately noticeable is that the fifth edition is packaged as one book. While still using the BRP engine, fifth edition considers itself a stand-alone RPG, not an adaptation of BRP. Fifth edition has more art, most of it highly stylized black and white works with patterns of eyeballs, tentacles, and fanged mouths. Compared to the first edition, it mainly has more: more mythos creatures, more spells, more occupations and skills for player characters, more scenarios, a bit more background information. In the fifth edition, there are rules for expanding the setting to different eras: not just Lovecraft's original 1920's settings (which, after all, were contemporary for him), but also the 1990s (contemporary for fifth edition) and the 1890s. It is better organized, too.

There are a few noticeable changes in the rules. There is a flowchart to clarify the character generation process. All firearms have a malfunction value, not just automatics (roll too high on your attack roll, and your gun will jam or misfire). Characters have skills for types of firearms (handguns, machine guns, shotguns, and submachine guns), and may also obtain skills in individual weapons (such as 9mm automatics), so that they are particularly skilled with one gun, but can also use others. A major change in the play of the game is in spell names. In the first edition, spell names were simple and functional: "Summon/Bind Byakhee," for example. In the fifth edition, these are still the names listed in the rules, but Keepers are told to never refer to spells by these names. Instead, when investigators find spells, they are to be given period flavor names, such as "Speak with ye most ancient foulness," leaving Investigators to determine exactly what the spell does. On the whole, there are remarkably few changes for a game system after eleven years; this is a sign of how well thought out and adaptable the BRP system is.



We strongly believe Call of Cthulhu represents a product that was done right the first time, demonstrated by the small changes in our later edition. The game has consistently been a presence at gaming conventions, and continues to draw in new fans. Chaosium even released a d20 version. (You can reach Chaosium's webpage at CoC was quietly revolutionary when it first came out, and remains fresh twenty years after its introduction.

Call of Cthulhu also presents interesting role playing challenges. Player characters, while heroes, can rarely afford to be heroic. Madness and death await those who learn too much too soon, and the background of the game, whatever era it is set in, includes a mundane world of laws and authorities who will hinder trigger-happy characters. One can rarely afford to confront the bad guys, guns blazing. The villains hardly suffer from such constraints themselves. Investigators barely enjoy the fruits of their successes, knowing that each one is temporary until the stars finally come right and the Great Old Ones must rise again, wiping humanity from the earth. The Investigators may be depressed, but for players, it can be a thumping good time.

The problem for players is keeping it fresh: the basic idea is that Investigators are ignorant of the Mythos. The more experienced a player is, the harder it must become to generate yet another neophyte Investigator. This gives the game a limited lifespan for a group of players. It is difficult to conceive of playing CoC for ten years at a stretch, the way we used to play AD&D. One way around this limitation is the epic campaign, currently represented by the magnum opus Beyond the Mountains of Madness. This 438 page tome (nearly double the thickness of our fifth edition rulebook) has seventeen chapters, each one detailing a new phase of the investigation. The problems of running such a beast are manifest, but what a beauty of a campaign it would be! A second option is a change in the game's orientation: the excellent Delta Green sourcebook put out by Pagan Publishing shows a completely different take on Call of Cthulhu, where the ability of players to quote Lovecraft from memory would do them little good in this shadowy conspiracy game where not much is what it seems to be. Dennis Detwiller has managed to beautifully merge Lovecraft's pessimism with modern conspiracy theory to create a grim game setting indeed.


Personal Note from the Curator

I have longed to play this game ever since I discovered it existed. Oddly, I have only played it three times, at gaming conventions. While I remember next to nothing of the first two games, the third chilled me to the bone—although this was more due to the setting of the scenario, in the trenches of the Great War, than to Cthulhoid monsters. Nevertheless, I am a big fan, and I truly do hope to uncork some of those epic campaigns someday.




Back to the Horror Wing
Back to the main lobby