IC: Ravenloft / Cthulhu West Marches game...
What I mean by that is:
Ravenloft. The Demiplane of Dread; the Realm of Terror. Ravenloft is Gothic Horror D&D, pure and simple. It’s darker, more frightening, and the monsters are tougher. Gothic horror is more atmospheric and dread-based than jump scare and gore-based. Foggy moors, decrepit castles, prophecies, fortune tellers, and madness.
Cthulhu. Relatively normal or low-powered people taking on forces and beings far beyond their comprehension. They investigate the strange and unusual, discover dark secrets, and fight the monsters as best they can. But those secrets have a price, and it’s often madness. Characters investigating strange murders and rumors of nefarious cults.
West Marches. Player-driven adventures with no pre-defined plot that takes place in a persistent world. In this case, a Cthulhu Mythos-infused Ravenloft. If interest is low (4-6 players), then that will be the regular group. If interest is higher (10+), then we will have player-selected rotating groups.
Curse of Strahd will be available if players choose. But Ravenloft is far more than the castle, Strahd, and the valley of Barovia. An ever-shifting demiplane surrounds the valley. All manner of horrors await beyond the mists...
Rule set. Low-level D&D 5th Edition with Call of Cthulhu Sanity rules.