Been on a retro horror run of late, some highlights:
Sleepaway Camp (1983). This is an objectively bad movie that paradoxically reaches greatness through its weirdness and ineptitude. This is the perfect slasher movie for 2023! If you haven't seen it, or better yet don't know about its infamous "Twist" ending, then this deserves to be on top of your list! The first sequel is pretty good too, although its knowingly way more camp (no pun intended) to the extent its as much a comedy as horror.
Prince Of Darkness (1987). This for me, and it seems for other people, is the true unsung gem in John Carpenter's back catalog. Equal parts inspired by Argento and Nigel Kneale's Quatermass series, its an absolute gem. And while you're at it, give Halloween 3: Season Of The Witch (1983) a second chance, taken from an uncredited Kneale script its another weird SF/horror hybrid and is woefully underrated due to it being a Michael Myers-free tale saddled with the Halloween franchise name.
Blood On Satan's Claw (1971). This early British folk-horror tale started out as a portmanteau of stories with a wraparound, but somewhere along the way got massaged into an uneven but singular narrative. Its a genuinely creepy and transgressive little movie that although marred somewhat by a rushed ending is well worth your time. I know a lot of people raved about Robert Eggers' The Witch for its atmosphere and period setting, but for me anyway, this movie is the real deal.
Waxwork (1988). This video-store staple is an absolute ton of fun. Low budget, but high-effort in all respects. I was genuinely delighted by how unexpectedly well this held up after all these years. An ideal watch on a double-bill with the similarly campy but fun Wishmaster (1997), which is similarly entertaining despite its many flaws.