First time to try this and with my life partner, at that. Compiled this list together with her. I'm not a fan of horror films but for her I'd go through these 31 terrifying moments (most probably with my eyes closed and me squeezing the life out of her hands).

Below are our choices per rule:
6 countries:
USA, South Korea, Austria, Italy, Spain, UK

8 decades:
50’s, 60’s, 70’s 80’s, 90’s, 2000’s, 2010’s, and 2020’s

2 post apocalyptic or natural disaster related films:
1. Dawn of the Dead (1978)
2. 28 Days Later (2002)

1 film with Robert Englund:
1. Dead and Buried (1981)

1 something is underground film:
1. The Descent (2005)

3 Satan/Devil centered films:
1. Rosemary’s Baby (1968)
2. The Devil’s Advocate (1997)
3. The Omen (1976)

1 Amicus film:
1. Tales from the Crypt (1972)

The worst Dracula film (by Letterboxd rating) that we haven't seen and we can access:
1. Dracula 3D (2012)

1 LGBTQ+ connected film:
1. The Lost Boys (1987)

5 Films from De Palma, Wes Craven, Ken Russell, Hitchcock and/or Moorhead & Benson:
1. The Birds (1963)
2. A Nightmare on Elm Street (1984)
3. Spring (2014)
4. The Endless (2017)
5. Frenzy (1972)

2 Peter Cushing films:
1. Tales from the Crypt (1972)
2. The Hound of the Baskervilles (1959)

1 film based on a work of or invoking the name Bram Stoker:
1. Nosferatu (1922)

1 film based on a Clive Barker story:
1. Candyman (1992)

2 films that were released the year that we turned 10:
1. REC (2007)
2. Night of the Comet (1984)

1 Mario Bava film:
1. Black Sunday (1960)

1 film with an 'x' in the title:
1. X (2022)

And 1 Tobe Hooper Film (There must ALWAYS be a Hooper film):
1. The Texas Chainsaw Massacre (1974)