Horror movies take many forms. While some are interested in creating monsters and serial killers that the protagonists have to avoid, others are more about building the mood and terrifying the viewers. There are also movies that attempt to gross the viewer out, considering that more important than even scaring them with the spooky story or the sudden attacks.

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While mainstream audiences like to be scared, by both jump scares and unstoppable killing machines, it is often the terrifying mood movies and the horror movies relying on the gore that turn those regular moviegoers away in droves. It is in these cases that many members of the audience will walk out of the theater, turn off the TV, or otherwise just say nope and move on.

Cannibal Holocaust (1980)

The documentary crew witness a ceremony of the "cannibal" tribe

Released in 1980, Cannibal Holocaust was one of the biggest offenders when it came to the video nasties. To this day, many film fans consider it one of the most controversial movies of all time. This was part of what was known as the Mondo Exploitation films which presented itself as a documentary rather than a fictional movie.

That makes it a sort of precursor to the found footage movies today, but this was horrific enough that it turned many viewers' stomachs. The movie is about a movie crew going to make a documentary about a tribe in the Amazon and cannibalism ensues.

Martyrs (2008)

Opening scene from Martyrs with woman holding shotgun

Released in 2009, Martyrs was part of the New French Extremity film movement. This was the name of the movement where horror movies worked to become more visceral with explicit gore, torture, and more. Martyrs fit comfortably into that movement.

The movie is about two women tormented by a demented cult who believes that torture will lead them to the awareness of the afterlife. The movie is brilliantly made, but the relentless torture made many viewers want it to end.

A Serbian Film (2010)

Milos is covered in blood in A Serbian Film

When A Serbian Film came out in 2010, it was instantly controversial and was considered one of the most hated movies ever made. It has a rotten score from both audiences and critics on Rotten Tomatoes and for good reason. This is a movie so disturbing that it isn't recommended for even horror fans.

A semi-retired porn star goes to work on an art film by an independent pornographer. When he realizes the movie they are making is even something he wants nothing to do with, he is drugged and forced to complete vile acts. The ending is even worse, for those who force their way through the movie.

Salo, Or The 120 Days Of Sodom (1975)

An image from the movie Salo.

One of the more critically acclaimed horror movies that most people stopped watching before its conclusion is Salo, Or the 120 Days of Sodom. The movie even received a prestige Criterion Collection edition, showing that even depraved horror movies had their fans.

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The movie is based on 120 Days of Sodom by Marquis de Sade and has four Italian libertines abduct a group of teenagers. They then subject them to months of torture, violence, murder, and sadistic acts. The movie was banned for graphic violence in many countries.

Hereditary (2018)

Annie screaming at Steve's death in Hereditary

Ari Aster has made quite a name for himself with his disturbing movies, and none are more successful than his 2018 horror movie Hereditary. The movie was clearly a success and made a lot of money, so it is clear that people were able to watch it all the way through.

However, there were just as many people who stopped halfway through and just walked away never to return. When a little girl is decapitated, her mother and brother begin to realize that a demonic cult might have plans for them. From the little girl's death to Hereditary's terrifying ending scene, this is a movie that gave people nightmares.

The Human Centipede 2 (2011)

A man laughs while covered in blood from The Human Centipede 2

Honestly, all three Human Centipede movies are worthy to add to the list of horror films that people backed out of. The fact that the first two were successful enough for a third is shocking itself. However, of the three, the second movie is the hardest to get through and the one that is most disgusting.

The movies involve a deranged scientist who wants to create a human centipede, which involves suturing people together in a mouth-to-anus procedure. The second movie has a fan of the first attempting to do it himself in terrifying ways.

The Green Inferno (2013)

A still from the 2013 horror movie The Green Inferno.

Eli Roth has made a lot of movies that were controversial. His Hostel movies had many people turning off their TVs and Cabin Fever was gory enough to make anyone sick. However, none brought as much controversy as The Green Inferno in 2015.

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Similar to Canibal Holocaust, this movie featured people traveling to the Amazon rainforest, only to find an indigenous tribe that brutally tortures them and then begins to eat them. Not only did people turn away due to the disgusting gore, but the depiction of the indigenous people was also enough to turn many heads.

The Last House On The Left (1972)

The killers in The Last House On The Left.

Wes Craven got his start with one of the most controversial movies of the 1970s. This horror movie was The Last House on the Left and showed a depiction of two girls being brutally raped and murdered by some people in the woods. However, it all came back around when they sought shelter in the home of one of the girl's parents, and karma came back to get them.

The movie was one of the video nasties, and a lot of people couldn't get past the brutal rape in the first half of the movie. What might be shocking to many people is that this was actually a remake of a classic Ingmar Bergman movie called The Virgin Spring.

Antichrist (2009)

Willem Defoe in the promo photo for Antichrist.

Anti-Christ featured a lot of moments that made viewers want to shut it off and forget about everything they just watched. It all started off with a moment that turned many viewers away instantly, as the young son of a couple fell out of a high-rise window and died while his parents had sex.

What followed that was even harder to get through as the parents, played by Willem Defoe and Charlotte Gainsbourg, put themselves through hell and mutilation to atone for their perceived sins. This is a movie that fans will only watch once - if they even get through that much.

Raw (2016)

Justine in a scene from Raw, biting her sister

Released in 2016, Raw was a horror movie about a young vegetarian girl's change after she changed her diet. The basis of the movie has the girl taste meat for the first time, and that completely changes her life, leading her to a path of destruction.

Justine eats a rabbit kidney and then wants to eat nothing but meat, finally leading to cannibalism. The movie has a great coming-of-age story and is also about female empowerment. However, the shocking violence and gore-fuelled visuals made this a hard movie for many viewers to get through.

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