In Pathfinder 2e, you’ll more likely get a chance of martials getting more crits than anticipated than wild spellcasters moves haha.

It can be done… but only by making the monster unfightable. Not “too strong”, literally invincible. To some, that’s horror enough haha.

That said, horror games are indeed the perfect setting to try out other systems, there are some out there like Mothership where the rules hold on one page.

Technically PF2e has Crit Success, Success, Failure and Crit failure, but I somehow I don’t think you are looking for that if you want something similar to PbtA haha.