Finding a really good horror movie is really a treasure, since the vast majority of horror movies out there are either mediocre or terrible.
I have personally always loved the aesthetic of 80s style practical effects in horror, Cronenberg is the king in this area, but John Carpenter has also made some really great contributions with stuff like The Thing and In The Mouth of Madness. The Evil Dead series is a classic because it strikes a great balance between absurdist humor and surreal, visceral horror that is quite hard to replicate. I would say that the film that best approaches that sort of balance, but with a very different visual style, would be the film Herbert West: Reanimator, which is honestly my favorite cinematic-adaption of any Lovecraft story because of how well it leans into the sort of trashy, pulp-novel aspect of his work that more "serious" adapters shy away from. I really enjoy that movie, I would say for anyone else who has seen it and wants more in that vein should check out From Beyond and Society (though, I should warn you, they are both extremely sexually explicit and nsfw) because those were made by some of the same people behind Herbert West.
