Building on fond memories of other random generators, what might a random Trail of Cthulhu adventure generator look like? The tables below generate a highly random Trail mystery. As with all random generators, the goal is to prompt the Keeper’s creativity in connecting disparate elements – don’t expect coherence from random rolls alone!
Adventure Hook (d12)
Why do the investigators get involved? (You can also use this as a way to determine the theme or atmosphere of the adventure if you’re not using pregenerated characters.)
- Artistic Sensitivity
- Bad Luck
- In the Blood
- Sudden Shock
- Thirst For Knowledge
(The drives Ennui and Follower aren’t used in the list above.)
Where does the adventure take place? The somewhat eclectic list of suggestions below is based on the locations discussed in the Trail of Cthulhu rulebook.)
- United States – Rural
- United States – Small Town
- United States – Urban
- United States – Lovecraft Country
- Abyssinia/ Belgian Congo
- Saudi Arabia
- Soviet Union
- Easter Island/South Pacific Mandate
Apparent Situation (roll 1d20)
What are the investigators doing here?
- Commercial interest – it’s related to the business of an investigator, like a real estate deal
- Investigate disappearance – of a friend, relative or other acquaintance. Or a strange, if the investigator is a police officer, detective or other specialist.
- Investigate untimely death – as above.
- Investigate cryptic events – lights in the sky, strange footprints, sinister letters.
- Investigate criminal activity – bootlegging, extortion, theft
- Investigate alleged supernatural event – ghosts, seances, vampire attacks, curses.
- Investigate medical mystery – strange disease, sudden madness
- Investigate prodigy – fallen meteorite, brilliant scientific discovery
- Carry out personal errand – execute a will, return a book borrowed years before
- Carry out mundane task – something connected to the investigator’s occupation
- Carry out official duties – as above, but a little more formal and significant
- Survey site – examine a location in detail, for commercial or archaeological reasons
- Report on story of interest – even if the investigator isn’t a reporter, they might be asked to look into a local mystery
- Research local history – as a hobby, out of antiquarian interest.
- Visit distant cousins or aged relative – haven’t seen them in years, I wonder what they’re up to
- Visit old friend or correspondent – as per Henry Akeley in Whisperer in Darkness
- Vacation or (recuperation after traumatic experience) – just what you need after that last nightmarish encounter
- Vehicle breakdown or travel delay – you’re stuck here for a while
- Drawn here by strange dreams – because you’re a Lovecraftian protagonist
- Seeking mysterious object or book – that has recently come to light
Horrible Truth (roll 1d12)
What’s really going on?
- The Apparent Situation is the true situation
- There’s a CULT here, and their activities may be exposed by the Apparent Situation
- There once was a CULT here; it’s mostly moribund, but some horror connected to the cult lies buried here and may be exposed by the Apparent Situation
- There’s an active and ambitious CULT here; the Apparent Situation is connected to some malign intent of theirs.
- There’s a CREATURE here, disinterested in humanity unless provoked.
- There’s a CREATURE here, preying on humanity.
- There’s a CREATURE here, slumbering – but it may be awoken by the Apparent Situation.
- The Apparent Situation was triggered by a TOME OR ARTEFACT
- Someone’s using the Mythos for personal gain using a TOME OR ARTEFACT
- There’s a GOD OR TITAN slumbering here, and its presence disturbs the world
- There’s an ancient ruin or tomb connected to a GOD OR TITAN here, guarded by a (1-3: CULT, 4-6: CREATURE)
- There’s a clash between two entities (roll 1d6 for each: 1-3: CULT, 4-5 CREATURE, 6 GOD OR TITAN).
Roll on the the Cult Size, Cult Status, Cult Intent and Blasphemous Rites tables.
Cult Size (roll d6)
- A single sorcerer
- A small cabal (a single family, a few locals)
- A congregation (two dozen or so)
- Endemic in the area (lots of people in the area are involved)
- Far-flung (only a small cabal here, but the cult is spread across the world)
- Great conspiracy (cult is world-wide and exceedingly well connected)
Cult Status (roll 1d6)
- Dead – no cultists left, only their works
- In decline – only a few left
- Secret – cult is hidden and mostly inactive, only performing rites on rare occasions
- Active – cult continues its sinister practices
- Recruiting – cult seeks new members
- On the verge of triumph! – cult is about to take a major step towards its goal
Cult Intent (roll 1d6)
- Worship of CREATURE with offerings, sacrifice
- Worship of GOD OR TITAN
- Study of TOME OR ARTEFACT
- Acquisition of power
- Keepers of CREATURE
- Summon GOD OR TITAN, end reign of humanity.
Blasphemous Rites Include (roll 1d10)
- Worship outdoors at ritual site
- Worship at hidden temple, cave or ruin
- Bizarre surgical experiments
- Congress with CREATURE
- Use of drugs or extracts
- Ritual initiation
- Travel through dreams or magical gateways
- Use of ritual magic
- Ritual sacrifice
Creature (roll 1d100)
5-6 Black Winged Ones
9-10 Colour Out of Space
11-15 Dark Young of Shub-Niggurath
16-20 Deep One
21-22 Dimensional Shambler
23-24 Elder Thing
25-26 Flying Polyp
27-28 Elder Thing
29-30 Formless Spawn
31-32 Gaseous Wraiths
41-42 Great Race of Yith
43-44 Hound of Tindalos
45-46 Hunting Horror
71-72 Serpent Folk
73-74 Servitor of the Outer Gods
81-82 Son of Yog-Sothoth
85-86 Star Vampire
87-88 Ultraviolet Devourer
91-92 Vampirish Vapour
Gods & Titans (roll 1d20)
- Chaugnar Faugn
- Quachil Uttaus
Tomes & Artefacts (roll 1d20)
1. Necronomicon, original
2. Necronomicon, modern
3. Cultes des Goules
4. De Vermis Mysteriis
5. King in Yellow
6. Book of Eibon
7. Pnakotic Manuscripts
8-9 Idol of GOD or TITAN
10-11 Idol of CREATURE
12-13 Relic or Mummy of CREATURE
14. Remains of ancient sorcerer or priest
15. Ancient Stone
16. Dust or Elixir
17. Cryptic Machine
18. Weapon or Tool
19. Enchanted Place
20. Gateway or portal
Structuring the Adventure
As a starting point, assume 3-5 core clues must be discovered and 1-3 hazards must be overcome to complete the investigation.
Random Core Clues
- Art History
- Cthulhu Mythos
- Library Use
- Roll again, but it’s an impossibility
- Roll again, but it’s a personal connection
- Roll again, but it’s a terrible revelation
An Impossibility: This rock is older than the universe! This painting is moving! This library is carnivorous!
A Personal Connection: Your Medicine can’t tell you anything about this condition – but you do know a retired physician, Doctor Black, who lives nearby. Maybe he can help.
A Terrible Revelation: Oops! I just correlated hitherto disassociated fragments of knowledge. Rookie mistake.
- Assess Honesty
- Cop Talk
- Credit Rating
- Oral History
- Roll again, but it attracts the attention of sinister forces
Sinister forces: It’s not wise to ask questions about certain topics.
- Evidence Collection
- Roll again, but it’s an impossibility
- Roll again, but it exposes the investigator to something toxic or hazardous
Exposure: You see a strange light as you look through the telescope; you pick the lock, but discover the door’s a twist in space and time…
- Athletics – a chase scene, a physical obstacle
- Conceal – a hidden trap
- Disguise – you must infiltrate a group
- Driving – dangerous conditions or a car chase
- Electrical Repair/Mechanical Repair – a piece of equipment is vitally needed
- Explosives – it’s the only way to be sure
- Filch – you must steal something
- Firearms – a combat scene at range!
- First Aid – someone’s dying or badly injured
- Health – exposed to a toxin
- Piloting – we’re on a boat
- Riding – we’re on a horse
- Stability – keep it together, man!
- Scuffling – a combat scene, up close!
- Sense Trouble – there’s something out there.
- Shadowing – quick, after them!
- Stealth – you must infiltrate a place
- Weapons – a combat scene, with sharp bits
- Roll again twice
- It’s a combat scene, with a complication. Roll again for the second ability involved, other than a combat ability. For example, Riding implies a shoot-out on horseback; Stealth implies an assassination attempt.
Putting It All Together
Let’s roll up a random adventure and see what comes of it!
Our initial hook is SCHOLARSHIP, and our location is ANTARCTICA. Clearly, we’re on a scientific expedition – maybe the Starkweather-Moore expedition promised at the end of At The Mountains of Madness. It’s hardly worth rolling an Apparent Situation in this case. The Horrible Truth is that there’s a CREATURE preying on people – specifically, a BLACK WINGED ONE, the assassins of the Cthulhu cult.
Our key clues are: BUREAUCRACY, ART and OUTDOORSMAN, and our random hazards are FILCH and RIDING.
So… the expedition to the Antarctic includes a secret worshipper of Cthulhu. He summons up a Black Winged One to kill other members of the expedition, for he seeks to get to the glacier where Cthulhu slumbers. Bureaucracy reveals that someone infiltrated the expedition under an assumed name, Art (plus Filch) means the investigators steal the cultist’s sketchbook and see his crazed scribblings of a buried god, and Outdoorsman & Riding imply a desperate sleigh-dog chase scene across the frozen wastes!
Another random attempt yields:
ARROGANCE for our hook, SPAIN for our location, VACATION for our Apparent Situation. That sounds like a bunch of idealists charging off to volunteer in the Spanish civil war. The horrible truth is that there’s a clash between two Cults.
The first Cult is a lone sorcerer who’s on the verge of triumph – he seeks to acquire power, and his blasphemous rites include Ritual Initiation.
He’s opposed by a second cult that Endemic in the Area, highly Secret, and worships… hmm. The Tcho-Tcho. Their rites include congress with a creature – rather an involving a second race, let’s assume it’s congress with Tcho-Tcho. Presumably, there’s a connection between the Plateau of Leng and the Meseta Central.
Obviously, if it’s the Spanish civil war, then the two cults are on opposite sides. A Communist sorcerer? Fascist Tcho-tchos? Or the other way around?
Our core clues are INTIMIDATION (Interrogating a prisoner, maybe?), OCCULT and COP TALK; hazards are Piloting and Sense Trouble.
So – the investigators are volunteers on the Republican side. Interrogating a prisoner, they learn of a fascist plot to bomb mountain villages. (Time to do some research on aerial bombardment and air power during the Spanish civil war; Guernica can be a touchstone here). OCCULT discovers the villages are being targeted because of their connection to the Tcho-Tcho cult; the investigators need to use Piloting and a borrowed biplane to shoot one bomber down before it commits the mass sacrifice needed a portal to Leng and the triumph of the Nazi sorcerer behind the bombing plan. Cop Talk and Sense Trouble warn the investigators that their Tcho-Tcho-worshipping allies will turn on them after the fighting’s done, and they should head back to the safely of the lowlands if they hope to survive…
Trail of Cthulhu is an award-winning 1930s horror roleplaying game by Kenneth Hite, produced under license from Chaosium. Whether you’re playing in two-fisted Pulp mode or sanity-shredding Purist mode, its GUMSHOE system enables taut, thrilling investigative adventures where the challenge is in interpreting clues, not finding them. Purchase Trail of Cthulhu, and its many supplements and adventures, in print and PDF at the Pelgrane Shop.