The words 'supervillain' and 'mean' go hand in hand. The job of supervillains isn't just to fight the superheroes, their job is to keep the game alive. The more scandalous villains are, the more watchable they become. As villains cross their mean quota, they achieve the title of supervillain. Some of them play the game with the sole objective of doing the exact opposite of what the good guys do. But that's what makes them interesting.

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The word 'mean' could have different connotations but, in this list, we look at the most ruthless, violent and heartless supervillains that have existed in the world of comics.

10 DARK PHOENIX (MARVEL)

Although Dark Phoenix the movie may have bombed at the box office, the horrors of The Dark Phoenix Saga are still very much alive in fans' memories. Dark Phoenix started out as a hero within the X-Men, but slowly loses control of her inner self.

Jean Grey's Dark Phoenix was created by Stan Lee and Jack Kirby in The X-Men #1. She had powers of telepathy and telekinesis and, over time, her powers increased, turning her into an Omega-level mutant and a physical manifestation of the fearsome cosmic Phoenix. Which would have worked for the good guys, if Jean hadn't lost her mind. In the comics, there are accounts of her physically torturing and killing people for no reason. The worst thing that Jean has done is to reject her own daughter, Rachel Summers who came from the future to see her.

9 BULLSEYE (MARVEL)

Bullseye is to Daredevil what Joker is to Batman. He's butted heads with Daredevil on countless occasions. He stands out on account of him not only harming his arch-nemesis but also harming the ones that Daredevil loves. The chilling horror of Bullseye killing Elektra with her own sai in front of Daredevil is etched in memories of fans. Elektra crawled her way to Daredevil's place and died in his arms, all while Bullseye watched.

Bullseye has been charged with manslaughter, was a part of the Dark Avengers, and the Thunderbolts, to list but a few things. He even tried to kill Kingpin while still on his payroll. He is the standard for a mean supervillain.

8 VENOM (MARVEL)

Venom is a distorted Spider-Man, a cross between an alien symbiote and an ordinary human who resented Spider-Man. He occupies a position in the list because of his varying morality, in that he has spared those he deems innocent. But, once his dark side kicks in, he will not spare anyone in his sight. The very appearance of Venom is chilling, let alone his ability to come back like a plague each time he's defeated.

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Venom has gone on to break Felicia Hardy's nose, murdering people in a church and threatened with human cannibalism on various accounts.

7 LOKI (MARVEL)

The staple supervillain, Loki Laufeyson appeared first in Venus #6 (1949). It was in Mystery #85 (1962), however, that the readers saw what he could pull off. From sowing seeds of discord to making Thor into a frog, Loki reminds us why the bad guys deserve two hoots.

Loki is capable of creating warring clans of superheroes, of uniting villains, sowing more seeds of discord, and attacking New York City. Loki has no chill.

6 DOCTOR DOOM (MARVEL)

Kill and conquer, that's Doctor Doom's way to go about things. Since he first appeared in Fantastic Four #5, Victor Von Doom has crossed every limit. Most of the time, with The Fantastic Four becoming his victims. He once kidnapped Sue Storm and forced her allies to travel back to the eighteenth century to steal Blackbeard's treasure.

Doom's plots mostly reflect his genius and ace sorcery that he has learned since his early days.

5 MAGNETO (MARVEL)

Magneto, besides being a scourge to the X-Men, has been a terrible father to Quicksilver and Scarlet Witch. You'd think, due to Magneto's first-hand account of the Holocaust, he'd know the price of human life, but no. Magneto's most mean and unforgivable act to date is that he abducted his own children from their mother Magda.

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Later in the story, he forces Quicksilver and Scarlet Witch to join the Brotherhood of Mutants to wreak havoc on the Earth. In X-Men: Days of Future Past, he was also in Dallas on the day President Kennedy was assassinated. Just saying.

4 THANOS (MARVEL)

Thanos may not be the most powerful supervillain of all time (Infinity Gauntlet, aside), but he certainly is one of the meanest. Not only did he start by killing off Loki in Infinity War but he seemed to make no fuss over it. He also forced Scarlet Witch to watch Vision die again and sacrificed Gamora for his mission. But these are standard supervillain gimmicks.

The worst thing that Thanos could do was perform his snap. And just like that, with his Infinity Stones, he turned half the universe's population into dust.

3 DARKSEID (DC)

The god of Apokolips and the literal God of Evil, Darkseid has caused mayhem ever since he was first created in 1979 by Jack Kirby. This supervillain broke bad by killing his own brother, his concubine and the Amazons. Darkseid's meanest act has to be the use of the Anti-Life Equation.

The Anti-Life Equation is the sole pursuit of Darkseid with which he regained control of the planet Apokolips. As he also conquered Earth, he planned to spread the Equation slowly to the entire universe. Only after the Justice League stepped in was Darkseid sent back to where he came from.

2 DEATHSTROKE (DC)

Deathstroke first appeared in New Teen Titans #2. He served in Korea in the early part of his career, eventually training child soldiers for a living. Deathstroke, by nature, is a mercenary without any heart. As long as he is paid, he will kill just about anyone and anything.

In the DC Comics New 52, Deathstroke even killed his own son, Grant Wilson. Rose Wilson, his daughter, came to him to start on a new slate, Deathstroke instantly offered her the role of his sidekick. But he kept injecting her with an enhancement serum, turning her insane in the end.

1 JOKER (DC)

Joker is undoubtedly the boss of all villains in every sense of the word. Joker is the antithesis of Batman. In countless story arcs, Joker has crossed limits to try and break his hero. He stands out because of his twisted ethics, on murder, dependency, love, romance, debauchery, treachery and humor.

Supervillains look like carbon copies of each other most of the time. But not Joker. There can never be a supervillain to dethrone him. It isn't easy to put on a smile while killing Robin with a crowbar. But the way Joker does it is poetic justice to his birth and origin. Without Joker, there would be no Batman. Without Batman, DC wouldn't be DC.

NEXT: The 16 Worst Things The Joker Has Ever Done