Here to yearn. Special shoutout to Hooptober creator, Cinemonster (original list and what this is about found here: Hooptober XII). This list will probably change, but attempting to do no overlaps wherever I end up. Also adding a few extras because I am greedy.

Rules: There must be 31 horror films (minimum)!

6 countries (other than Italy or US):
Argentina - History of the Occult (2020), When Evil Lurks (2023) 
Iceland - Lamb (2021)
France - Frontier(s) (2007)
Germany - Nothing Bad Can Happen (2013)
South Korea - The Wailing (2016)
Japan - Audition (1999), The Ring (1998)

9 decades:
2020s - The Shrouds (2025), Frankenstein (2025)
2010s - The Love Witch (2016), Mandy (2018) 
2000s - The Devil's Backbone (2001)
1990s - Twin Peaks: Fire Walk with Me (1992), Braindead (1993)
1980s - Henry: Portrait of a Serial Killer (1986), Opera (1987) 
1970s - House (1977)
1960s - Night of the Living Dead (1968)
1950s - Them! (1954)
1940s - Cat People (1942), The Wolf Man (1941) 

5 Zombie Films:
28 Years Later (2025)
Train to Busan (2016)
One Cut of the Dead (2019)
Fido (2006)
Planet Terror(2007)

3 cult or conspiracy horror films:
The Invitation (2015)
The Endless (2017) 
The Empty Man (2020)

1 film from a Black director with a Black lead:
Blacula (1972) by William Crane w/ William Marshall as lead, His House (2020) 

1 film from a Mexican or Central American director:
Tigers Are Not Afraid (2017) by Issa Lopez, Cronos (1992) by Guillerno Del Toro

1 Canadian film:
Videodrome (1983) by David Cronenberg

1 former Soviet state film (Armenia, Azerbaijan, Belarus, Estonia, Georgia, Kazakhstan, Kyrgyzstan, Latvia, Lithuania, Moldova, Russia, Tajikistan, Turkmenistan, Ukraine, and Uzbekistan)
Russia - Viy (1967)

The most popular film from the 1940s that you haven't seen and can access..
Dead of Night (1945)

2 Post Apocalyptic horror films:
Delicatessen (1991)
10 Cloverfield Lane (2016)

1 Film with dreams or a dream as part of the plot:
Wes Craven's New Nightmare (1994)

1 The animals are pissed at us film:
Cujo (1983), The Birds (1963)

1 Silent film:
The Fall of the House of Usher (1928)

4 based on Novels: 
Frankenstein (1932) adapted from Mary Shelley's novel. 
The Thing (1982) based on John Campbell Jr's novel "Who Goes There?"
The Devil’s Advocate (1997) based on 
Andrew Neiderman’s novel of the same name.  

*Any film from THIS list that you haven't seen:
Possession (1981)

1 Ernesto Gastaldi written film:
All the Colors of the Dark (1979) 

1 film from 1932:
Freaks (1932)

I have never made a specific film a part of this before, but::
WIZARD of OZ ('39)

**And 1 Tobe Hooper Film (There must ALWAYS be a Hooper film):
Lifeforce (1985)

***FOR THOSE THAT LIKE TO DO EXTRA WORK:
Burn Witch Burn (1962)
German Chainsaw Massacre
Trick or Treat (1986)