Several years ago I backed the Call of Cthulhu 7th ed. Kickstarter, and while it has been a really long road, the end is now finally in sight. One of the things that was funded with that Kickstarter which was delivered recently was the long-awaited Pulp Cthulhu supplement. The backers received the pdfs for this book mid last month, and I spent the last several days reading and digesting it.
The book overall is very good, but the system while improved for the kind of game I like, it is still not nearly as good as Savage Worlds in terms of simplicity to prepare for and run. That does not however mean that there is no value in it. The adventures are good, I particularly like the last one, and the organizations are very interesting and could be incorporated into other settings pretty easily. My favorite bit however is Chapter 5 Pulp Sanity.
Pulp Cthulhu introduced the concept of talents to the Call of Cthulhu which are similar to edges in Savage Worlds, and in chapter 5, we are introduced to the concept of Insane Talents. These are talents that you get when you are driven insane, and can use even after a return to sanity at cost to your sanity. These talent can improve your senses, appearance, ability to drive, speed, give you the ability to understand a language that you don’t or change the way your skills work.
The last option in particular has some particularly interesting implications, especially with the added wrinkle that if you fail a roll using one of your insane talents, something particularly bad happens. One of the examples of this is for the swimming skill, where the insane talent alters the skill to allow you to breathe underwater, but with a partial success, you might awaken some dormant deep one ancestry.
This is something that I would consider incorporating into a game using the Horror Companion, Realms of Cthulhu, Weird War I, or Achtung! Cthulhu games. For the first three, I would say you can choose this as an edge when you get an advance with zero Sanity. For Achtung! Cthulhu, I would trigger this based on the Dementia trait. Each time you used the “Insane Edge”, it would cost you a point of Sanity (or Dementia).
This is probably not something that I would incorporate into a Rippers Resurrected even though it does have a sanity mechanic.