I've been creating Call of Cthulhu larps since 1997, first as a part of Serious Moonlight, then with the troupe Chuckling Cthulhu. Following some requests I have received from visitors to Unsolicited but Useful Advice For LARPers, here are some of my tips for running a Call of Cthulhu live-action event. Please note that I'm not going to discuss the specific variants - such as Delta Green, or Cthulhu By Gaslight. In the future, I might put together variant-specific guides, but for the moment, let's take a look at The Big Picture.
The First Rule
Keep your priorities straight. Say it with me: Plot first, props second. Plot first, monsters second. No-one is going to care about your carefully wrought flock of Mi-Go if no-one understands why they have manifested on the scene in the first place. Monsters and props are cool and fun, but the plot is the most important aspect of your game. Plotting can get frustrating some times, and the idea of making cool creatures (or, in my case, costuming) can be an easy escape from that stressor. A little bit of escapism is fine, but crafting that Deep One at the expense of your plot is a bad decision and you will regret it.
About Your Plot
-- Keep the plot low-mythos, unless no-one cares if their characters live or die - which might be the case if you're running a one-shot event. The monsters of the Cthulhu mythos are bad news, and they will kill player characters with shocking ease. That doesn't mean you can't have any mythos elements in the game - far from it. But you must keep the antagonists in scale with your protagonists. Generally speaking, it is beyond the realm of plausibility that a group could survive the return of Ry'leh - but they could certainly have a blast dealing with a gaggle of Deep Ones, or a cult of Shub-Niggarauth worshippers.
-- The effects of the Cthulhu mythos on a human mind is quite potent. Do not go by the published SAN system in the Cthulhu Live rules. I have discovered that, by those rules, SAN losses quickly snowball. For example: Mr. Jones sees a flesh-rotted zombie shambling across the croquet lawn. Blowing his SAN check, Mr. Jones gouges out his eyes, preferring blindness to the horrific vision that is heading towards the tea tent. Miss Smith witnesses this horrific act and, in turn, she loses sanity and does something equally awful right next to the town constable... You see how it goes. Create your own system for dealing with character sanity. In my case, I tend to handle it rather arbitrarily, myself - and run with that.
-- Put human elements into your plot, rather than relying on the mythos to provide the horror. The player-characters are human beings and as such, they are more likely to respond to - and be horrified by - other human beings. I have always maintained that the notion of a bunch of cultists eating the still-beating heart of a sacrificial victims will frighten your players far more than the notion of a Dimensional Shambler trashing the vicinity. If you're skeptical, go read Hannibal or American Psycho. Personally, I found those books far more disturbing than things like, oh, Steven King's early work which tended to feature A Horrifying Whatsit, rather than Horrifying People.
-- You don't need to be an expert on the mythos, but don't ignore your source material. Read Lovecraft, Derleth et al, to remind yourself of the original feel of early 20th Century gothic horror. It's a little campy, a lot creepy and usually centered around a hapless and/or arrogant men and women getting into things they shouldn't have. Keep that in mind whilst crafting your plot and creating characters. Those stories were character-centric, as well as driven by action - both elements contribute to a successful game.
-- Timing is (almost) everything. Give suspense time to build, and mysteries a chance to churn and bubble. Don't be throwing mysterious monsters and knife-waving cultists at your players thirty-minutes into the game unless you've planned to run a very short event - or you love running combat scenes. I'm not keen on either of those scenarios, myself, so I tend to hold back the heavy-hitters for at least the first sixty minutes when running a four hour event. If you're planning to run something longer than that, you might want to consider holding off the SAN-bashing stuff for several hours, but you don't want to hold off for too long. Your players are going to be expecting some sort of spooky and/or horrifying occurrence. Give them what they want - but you don't have to give it to them in a manner they're expecting. Surprise 'em!
-- Lulls in the first half of the game are okay. That is going to happen as the PCs get to know each other, and sort out the factors in the mystery of the moment. By the time your second half begins, things will be jumping! Use that quieter first-half to lay down your subtle clues and foreshadowing - because when the characters are running in terror from The Bad Guy (or Thing), they aren't going to be inclined to notice that little symbol that has been etched onto the doorframe...
-- Every time I've run an event, the players always manage to romp through my plot in about half the time I anticipate. So, pile it on! They'll probably get around to it, I assure you!
-- However, don't over-plot your event. By that, I mean 'don't try to anticipate every twist and turn the plot will take, or what your players will do every moment'. Create the setting, the NPCs, the conflict and a mental list of "Victory/Defeat" conditions, and let your players go at it from there. The more you try to manage the progression of the plot, the more quickly it will go off on a tangent. Players are sensitive to feeling rail-roaded, so leave everything as open as you can. Be flexible! Your players will come up with ways to tackle your plot that you never anticipated - ask me about the "First Osage Milita" during Pandora's Carnival some time...
-- There is such a thing as too much horror. Don't be afraid to poll your players while you're putting your event together, and sound them out about possible taboos. For example, I once introduced a plot that featured a child molester and murderer. One of my players - a mother of a young daughter - was deeply upset by this plot. It's one thing to give a player the creeps. It's another thing entirely to reduce them to tears, out-of-character, and make them want to leave the game for good - which was what happened in that particular case.
That doesn't mean you have to avoid those plot elements entirely, but take special care to ensure that your sensitive players and those taboos don't intersect. If you're not sure about the situation, it's best to err on the side of caution. In the example I cited above, the GMs agreed not to feature child-abusive plots while the young mother remained with the troupe. It was a little thing for us, and a big deal for her - so it all worked out for the best.
That said, once you've polled your players for taboos, go nuts with what remains. If no-one has an issue with eyeballs, reach for the peeled grapes and ketchup, pronto! If no-one has mentioned a fear of cephalopods in particular, head over to Ernie's Fish Emporium for twenty pounds of calamari, etc.
Crafting Characters, Props and Other Things
-- I'll say it again: Plot first, everything else second. Once your plot is reasonably set, now you can go nuts with all those delightful other things, such as trying to figure out how you're going to create half a dozen deep-ones on a budget that makes an episode of Dr. Who seem lavishly well-funded.
-- If you are pre-generating the PCs, allow for some redundancy in skills, when crafting your PC stats - if you're going with a stat-based system, that is. If your plot is going to depend upon someone knowing about archeology, try to arrange matters so that more than one PC has that skill.
-- If you are letting your players create their own characters, encourage them to develop the character as fully as possible. The more effort a player puts into their character concept, the stronger a vested interest they have in keeping that character alive. Sometimes in CoC, the temptation to do the suicidal thing can get a bit strong, so do what you can to discourage players from pursuing that course until it's absolutely appropriate for them.
-- We've all been influenced by television and movies and the (usually) high production values therein. Unless you have a vast budget, or some talented friends, you are not going to be able to craft Hollywood-quality props and monsters. There's nothing wrong with that. Plot is the core of the game and, with that in mind, your players are prepared to use their imaginations and accept that the guy in khaki-jumpsuit and a Halloween mask is actually a slime-dripping Deep One. By the time something like that manifests, your players should be so into the plot that incidental things like home-made monsters will be...incidental.
During the Serious Moonlight event, Temple of Terror, our mythos-beastie was six bed sheets dyed unwholesome shades of brown and green, sewn together into one long strip, with some big eyes and home-made fabric tentacles sewn onto the front. Imagine an incredibly cheesy Chinese dragon operated by a couple of game-masters, and you're pretty close to Frederick the Fabric Fiend (he was our attempt at a Lloigor, btw). By the time the game's climax came around and Frederick was summoned, the players were so over-amped on fear and suspense that they were actually shocked by the monster's appearance. Sure, he was home-made, and looked it, but the players were so into the game by then, that it didn't matter. Granted, there was a lot of giggling afterwards, and that's just fine. Do your best, and take pride in that.
-- Make atmospherics work for you. I suggest you check out Creating an Ambiance for Your LARP. It's another one of my larp-advice columns, featuring tips for a wide range of budgets, from dirt-poor to blank-check.It's easier to get your players into the mood of a dark spooky mansion if they're in a setting that at least tries to evoke that, rather than a brightly lit cafeteria.
-- Subscribe to the Cthulhu Live list at Yahoo. Some very smart guys are on this list, and they are always willing to share great ideas about props, plots, the best place to buy biohazard stickers, you name it. They've saved my butt more than once!
-- Use the web. There is so much useful information out there. Research ancient sun-worshipping cults. Read about symptoms of obscure diseases. Find lots of tips on construction props and beasties. The web is a great tool, use it to improve your game!
Alright, I think I've covered all the basics. As usual, I want you to have fun
while you're running your game, but I also want to see more kick-ass Cthulhu
larps out there. After all, I want to play sometime! Good luck and have fun!