When it comes to down-right scary and terrifying supervillains in the Marvel Universe, few come close to Carnage, sworn enemy of both Spider-Man and Venom, symbiote spawned the nearly-unstoppable, red murderer.

Related: 10 Things You Didn't Know About Carnage

From defenestrating infants to killing for fun to torturing his doctor so that he can see the world as Carnage does, the list of what makes Carnage so bone-chilling is a long one. Though morality can be subjective at times, especially in the comic book world, very few people could argue that any of these actions fall into the grey section of the scale between good and evil.

10 He Killed His Grandmother Gleefully

Carnage pushes granny down the stairs

Long before becoming one with the symbiote suit, Cletus Kasady was a vicious serial killer who had no qualms when it came to murder and decimation. He tortured and killed his mother's dog with a drill, attempted to murder his mother via electrocution, and actually succeeded in killing his grandmother by pushing her down the stairs.

Those are some pretty sick ways to pass the time. In Amazing Spider-Man #361, it was even revealed that Cletus was convicted of eleven different murders.

9 His Relationship With Shriek Shows A Deep Love For Evil

Carnage and Shriek are OTP

Having a sadistic serial killer as your enemy who cares only for chaos and murder is bad enough, but knowing that Carnage has a sweet spot somewhere deep down for a supervillain named Shriek makes him all the more terrifying. Sure, a villain who murders on a whim and has no moral compass is pretty bad, but that same villain feeling compassion for another vicious being is too much.

It's too humanizing, and when Deadpool injured Shriek and almost had Carnage kill her, you kind of start to feel bad for the guy. That is just scary.

8 Forced Spider-Man To Turn To Venom For Help

Spider-Man convinces Venom to help him fight Carnage

While Venom is enormously popular and even has his own movie franchise, once upon a time, Venom was perhaps the scariest thing to creep and crawl into Peter's life. So much so that after Venom terrorized Mary Jane, she begged Peter to return to his classic blue-and-red Spidey suit as his updated uniform triggered her tremendously.

RELATED: Venom 2: 5 Things About Carnage The Sequel Needs To Have (& 5 It Can Leave Out)

With this context, the fact that Spider-Man had to reach out to Venom in order to take on his newest symbiote enemy, shows just how dire the situation was.

7 Forced His Nihilistic Views On The World By Murdering Its Citizens

Carnage only cares for killing and chaos

Cletus Kasady doesn't believe in anything except chaos and the death that comes with it. According to Cletus, it's the only way to freedom, and his union with Venom's symbiote offspring creates the harbinger of that liberation.

Carnage lives for the killing because his brutal childhood in an orphanage molded his belief that, hey, life is meaningless, might as well kill people, thus "freeing" them from their farcical lives. It's a way for him to try and justify his sadism and it is straight-up chilling.

6 The Body Horror That Came From Him Linking Up With A Shark

Carnage Shark

In Venom #25, a small piece of Carnage has globbed onto Eddie's brain and Venom must do everything in his power to extract the maroon, murderous menace. On an island filled with animals for Carnage to latch onto in an effort to take down Venom, things take a turn for the strange when Eddie's son uses a mind-link to help fight off Carnage with a Venom T-Rex.

The gruesome result of Carnage linking up with a shark was a terrifying act of body horror.

5 He Can See With His Entire Body Due To His Extra Senses

Carnage looking scary

Carnage is twice removed from Spider-Man, as he was the host for the symbiote suit, and because of this, neither Venom nor Carnage trigger Peter's Spidey-Sense, which is in itself a terrifying notion.

RELATED: Spider-Man: 10 Scariest Carnage Cosplays

However, when added to the fact that Carnage's unique evolution from being born on earth allowed his body to have superior senses, you have a supervillain that essentially can "see" with his entire body. Carnage's senses are so keen and sharp, it's as if his flesh has an ocular vision.

4 His Bloodlust Drove Him To Create A Cult With The Goal Of Releasing Knull From Klyntar

Despite being a nihilist who just wants to butcher people, Carnage does have a deep-rooted philosophy that dictates his love for killing. In Web of Venom: Carnage Born #1, Cletus is given more depth to his origin story and it is quite horrific.

Cletus died at birth, was sent to "hell," and was then saved by an entity named Knull, god of the symbiotes. This experience kicked off Carnage's bloodlust, having him create a cult that would ultimately release Knull from Klyntar in Absolute Carnage.

3 When He Overtook The Population Of A Small Town To Consume Them

In Carnage, U.S.A. Carnage traveled to a town in Colorado to do what he does best: take some lives. In an amazing feat, that is only eclipsed by how utterly horrific it is, Carnage was able to do so much more than kill people.

He used his body's insane abilities to not only spread throughout the town but to also "take over" the population, creating copies of himself with their bodies. He also slaughtered cattle and people alike for the purpose of devouring their flesh.

2 His Ability To Manipulate Those Around Him

Cletus Kasady in jail before bonding with the Carnage symbiote

Not only was Carnage able to start a "murder family" with Shriek and a Knull cult, he also has a way of just getting in people's heads. Case in point, Matthew Kurtz, his psychologist in Carnage: Mind Bomb.

Carnage was able to drill into Kurtz' brain and infect his mind with the symbiote by showing him "the truth", which was death, blood, and other atrocities. Kurtz ended up going mad, attacking and killing three of the guards of Ravencroft Institute, as Cletus calmly watched.

1 When He Made A Jacket Out Of The Spider Patrol's Tongues

Superior Carnage with his nasty tongue jacket

In the five-part comic Superior Carnage, Cletus was actually lobotomized and the Carnage symbiote was forced onto Dr. Karl Malus in a villainous plot designed by Wizard. While this version of Carnage was more clean-cut and actually wore some clothes, once Wizard's mental hold was severed, Carnage's true nature took over.

When Superior Spider-Man attempted to call for backup, Carnage reveals that he took the tongues of the Spider Patrol and made them into a jacket.

NEXT: Avengers: 5 Members Carnage Can Defeat (& 5 He'd Lose To)