Too many to count but I'm a huge horror fanatic. I think Doctor Sleep and The House That Jack Built have been my more recent favorites.
I despise violent productions when they're only about free entertainment. In this genre, maybe I was the most disturbed by Hostel (1 & 2) which is about a wealthy secret org kidnapping backpackers to torture them. Or The human centripede. I can't tell I'm enjoying them, but still masochist enough to satisfy the curiosity, once (no rewatch)
Curiously, I'm a huge fan of Kim Ki Duk movies, where violence can be rude & omnipresent (for instance, Pieta). I make the difference that it's a very realistic kind, I'd comment representative of the human's nature. I'd dare to say, not fictional, which I judge more rational to depict. When it's not the case, it brings me more in mind the human's disgrace, especially when they're botched for a quick buck (sequels)
Psychological fear is more my thing, if sophisticated. Most recently seen, Midsommar, about a sect with weird sacrifice rituals. Again, wasn't much a fan of the discomfort but at least it had a few cerebrally twisted scenes.
Or, It follows, Get out
4 fantastic ones, not well known neither having been quoted yet, so worth mentioning
neat vampire one
again from scandinavia
gorey, second degree pastiche
sweet comedy