Thought exercise: Dungeon Fantasy/1920s Cthulhu Mythos crossover

[Jürgen Hubert]

Background: Paizo has recently released the final installment of their "Strange Aeons" Adventure Path for the Pathfinder role-playing games. And in there usual "Continuing the campaign" chapter, they have an intriguing suggestion - instead of the "standard" campaign ending, the PCs end up as "spirit essences" stuck in the minds of 1920s Cthulhu Mythos investigators. These investigators would then be created by the Call of Cthulhu rules, though they get some boosts from the spirit essences lurking in their subconscious.

Of course, if I ever were to run this Adventure Path, I would run it with GURPS - and GURPS makes crossover games far easier, so transporting the characters directly should not represent a rules challenge as such.

A bigger problem is the overall mood - while the abilities of D&Desque characters might not be too out of place in Ancient Hyperborea, their abilities as written don't really fit the early 20th century. If magic is an ability that can be learned and used by anyone with Magical Aptitude without significant consequences, then the PCs might find themselves at the center of a magical-industrial revolution. Which would be an interesting game, but it does not really fit the "secret occultism" vibe of the Mythos.


So here is the thought exercise: How would you change how the abilities of Dungeon Fantasy* characters work so that they fit the general mood of a 1920s setting without changing the characters themselves?

Martial-minded characters will already be challenged by the different weapon paradigms of the time (guns!), so spellcasters should likely experience some hindrances - hindrances that encourage them to limit their spellcasting and keep it subtle, but without taking their learned spells away...



*While Dungeon Fantasy does not follow all the same paradigms as the Pathfinder RPG, it's close enough for our purposes.

[Proteus]

Change the system for spending Fatigue such that PCs need to "gather" it from the surroundings (a la Ritual Magic) rather than tapping their own reserves?

A wizard will still be of immense help in leisurely, investigative sequences, and might be able to "pre-load" an offensive spell if combat seems likely, but won't be firing off as many large spells in melee.

If FP reductions due to high skill are common, maybe increase FP costs across the board? That might encourage wizards to increase skill levels yet further, while the fighters are having to master entirely new weapon skills for firearms.

I'm not sure what you'd do in this situation with Power Reserves; making them useless seems like stealing already-paid points from PCs.

Or, on the other hand, maybe large chunks of the 1920s setting have no or very low mana? "Places of power" become valuable to both sides, and can be fought over with full abilities, but magic becomes much more constrained elsewhere.

[Jürgen Hubert]

Originally Posted by Proteus

Change the system for spending Fatigue such that PCs need to "gather" it from the surroundings (a la Ritual Magic) rather than tapping their own reserves?

That sounds good - do you have any specific system in mind?

If FP reductions due to high skill are common, maybe increase FP costs across the board? That might encourage wizards to increase skill levels yet further, while the fighters are having to master entirely new weapon skills for firearms.

I do not like encouraging ultra-high spell skill levels - even if the impact of FP reduction is limited, it is hard to balance resisted spells with them.

I'm not sure what you'd do in this situation with Power Reserves; making them useless seems like stealing already-paid points from PCs.

Maybe modify them with limitations, such as requiring special rituals to recharge. Blood sacrifices, tantric magic, whatever. However, the PCs will still have the same number of character points they have spent on their energy reserves - which will mean that they get larger.

Or, on the other hand, maybe large chunks of the 1920s setting have no or very low mana? "Places of power" become valuable to both sides, and can be fought over with full abilities, but magic becomes much more constrained elsewhere.

The modifiers from GURPS Cabal could also be useful to them - to make spells effective, you have to cast them under the right circumstances (although the flavor of decanic magic doesn't quite fit...).

[sir_pudding]

Mentalists, scholars and incantors are probably better fits than wizards. You could restrict clerics to elder clerics and chaos druids, too.

[Stone Dog]

The Arkham Horror set of games has gotten me thinking along these lines lately. It is probably more an Action setting than DF or Monster Hunters, though pulling inspiration from those two lines is basically mandatory.

[zedlopez]

Maybe working with mana is inherently traumatic in a Call of Cthulhu world as it risks opening your mind to how things really are. Roll a Fright Check at +Cost. (Cultists have some advantage/disadvantage combination that lets them use magic without the Fright Checks but at some other horrible cost.)

[Andreas]

Originally Posted by Jürgen Hubert

If magic is an ability that can be learned and used by anyone with Magical Aptitude without significant consequences, then the PCs might find themselves at the center of a magical-industrial revolution. Which would be an interesting game, but it does not really fit the "secret occultism" vibe of the Mythos.

That would not be a problem if Magery and high mana levels are extremely rare. In that case there would not be many who the DF characters could teach to cast spells. This does not necessarily mean that almost no other characters would be able to use magic, just that they would be using another magic system than the GURPS default one (which probably don't fit a Cthulhu Mythos setting anyway).

So here is the thought exercise: How would you change how the abilities of Dungeon Fantasy* characters work so that they fit the general mood of a 1920s setting without changing the characters themselves?

Martial-minded characters will already be challenged by the different weapon paradigms of the time (guns!), so spellcasters should likely experience some hindrances - hindrances that encourage them to limit their spellcasting and keep it subtle, but without taking their learned spells away...

To some extent the presense of guns could challange mages as well. Missile spells for example are less impressive when they compete with guns. It is true that other spells would still offer large advantages though. Especially if such effects are very rare in the setting.

Keeping it subtle without taking spells away might be difficult. Some spells are inherently flashy. Perhaps some kind of powerful organisation which hunts down people who publicly display supernatural abilities would be a decent solution. That could would leave many uses for flashy spells while still encouraging the characters to be careful in that regard and it would limit mages more than martial-minded characters.

[Jürgen Hubert]

Originally Posted by sir_pudding

Mentalists, scholars and incantors are probably better fits than wizards. You could restrict clerics to elder clerics and chaos druids, too.

In the campaign, characters start out in a normal Pathfinder setting with Pathfinder assumptions before they get to Earth, so I don't want to restrict them from taking iconic "classes" such as wizards or clerics before they even get there.

[sir_pudding]

Originally Posted by Jürgen Hubert

In the campaign, characters start out in a normal Pathfinder setting with Pathfinder assumptions before they get to Earth, so I don't want to restrict them from taking iconic "classes" such as wizards or clerics before they even get there.

In that case it is just regular DF templates with Amnesia. The Adventure Path doesn't change the normal Pathfinder rules, so why would a GURPS conversion be different?

[Jürgen Hubert]

Originally Posted by sir_pudding

In that case it is just regular DF templates with Amnesia. The Adventure Path doesn't change the normal Pathfinder rules, so why would a GURPS conversion be different?

But the PCs shouldn't forget who they are. My goal is to make them part of the fringes of the occult underground and other strange, hidden elements of 1920s Mythos Earth. But if they can use their powers as normal without any consequences, they will instead become headline news.