NPCs and the Cthulhu Mythos skill

[tendentious]

So I'm running a certain globe-spanning campaign. The Cthulhu Mythos skill of one of the players is rising surprisingly fast, thanks to a large supply of of the drug Liao that the party has acquired.

Out of curiosity, I flipped through the stats of the NPCs that might be encountered over the course of the campaign. To my surprise, most have relatively low Cthulhu Mythos scores - and some of these guys are immortal sorcerers dedicated body and soul to the Outer Gods. And all have 0 SAN, so the impact of CM on SAN is not a consideration.

I'm wondering whether the rationale here is the assumption that if you have a Cthulhu Mythos skill of - say - 95%, then you know 95% of all possible matters regarding the mythos: pre-human (and post-human) history, trans-dimensional horrors, spells, the works. So having CM of more than - for example - 50% suggests that the NPC is approaching god-like levels of awareness.

But surely the Cthulhu Mythos skill should be considered as other knowledge skills - relative to the available sum of knowledge for a particular time and place and people. An NPC in the 1920s with 95% Cthulhu Mythos skill is an expert in the sum total of information that is available to someone in the early 20th century. Most of this is drawn from mythos tomes; most of which are dated from the last thousand years or so, with fewer and fewer sources available the further back in time one goes. So the detail grows sketchier and sketchier with time and distance. And we know at least some of the information in the tomes is flat-out wrong; Abdul Alhazred denied that there were any shoggoths on earth! Shows what he knew!

And all this is still only a infinitesimal fraction of everything that is available to be known. And then of course there is everything that is totally beyond human comprehension!

Let's say you have a score of 95% in Cthulhu Mythos. Well, not you - but some immortal servant of the Outer Gods. You still have only a 19% chance of knowing anything about a subject that would be ruled to require an extreme success on a skill check - like a Historian inquiring after a piece of esoteric information in an period outside their expertise. And as for any knowledge relating to subjects that are hardly known at all in the present day - ancient Hyperborea; the civilisations of the serpent folk or the elder things or the great race; almost anything to do with the mi-go other than their colonies on earth and that one on Yuggoth - then your 95% CM score is going to do you far less good than a time gate spell, a space suit and some field research.

Now I am just talking about the NPCs, and of course I can give them whatever CM score I feel is appropriate. And it's difficult to remember a time when an adversary NPC ever had to make a CM roll. But when one of the PCs score in the skill is approaching that of a centuries-old servant of an Outer God - with a repertoire of spells that would choke a grimoire - I have to wonder about the bench mark when it comes to Cthulhu Mythos.

Side Note - if you use the optional rule for spontaneous use of Cthulhu Mythos to perform spells, then restricting CM would make more sense. A 95% chance to cast any spell you can think of? That might be a problem, except that we're talking about NPCs; they already have whatever spell they need (or that the Keeper feels they need) for the scenario. And it's a simple matter to simply change the requirement for spontaneous casting to making a hard or even an extreme CM success. Your regular success on the CM check means that you are aware of the spell and have some idea of how to cast it. But to actually perform the ritual successfully without practice? Like everything else, there is a large gap between academic understanding and practical execution.

 

Edited June 5, 2020 by tendentious

[EricW]

100% mythos skill does not mean you have enough power to challenge Nyarlathotep for mastery of the cosmos.

And you could make Liao trips a bit more hazardous, make the mythos gain unpredictable, include bouts of insanity, memory blanks - the player could suddenly find themselves in a nasty part of town, covered in blood, holding a knife, with no memory of what happened. Or the PC could suddenly manifest disturbing new skills, like Schwarzenegger in Total Recall, when he takes out an assassination squad after stirring up repressed memories of his dangerous alter-ego. Or maybe disturbing visions could start to manifest in waking life - if their body is saturated with Liao, maybe they are approaching the point they no longer need to take additional doses of the drug to experience its effects.

And of course there is a risk a malevolent person or entity being spied on by the player character could become aware of the PC, and do something dreadful - attack the PC, whisper blasphemous advice into their mind, even start to manifest in our time - the player maybe starts catching unexpected glimpses of this malevolent wizard in crowds, dark doorways, always just beyond reach.

Throw in a few of those memory losses and uncontrolled visions on top of a disturbing manifestation or two and I suspect your PC will panic and flush their remaining stocks of Liao.

 

Edited June 5, 2020 by EricW

[Lloyd Dupont]

I second that... while I have never played Cthulhu (oops, sorry) one has to remember this is an... *horror* RPG...
So, obviously it should not feel like the classical rise of power of other games... It should be descent into madness!  

[Dethstrok9]

1 hour ago, Lloyd Dupont said:

while I have never played Cthulhu

Hastur is coming to get you...

[Loïc]

2 hours ago, Lloyd Dupont said:

while I have never played Cthulhu

Never mind. Cthulhu's playing you since a long time...