It takes a big ego and lots of smarts to be one of Superman's greatest foes, and Lex Luthor has both in spades. The bald baddie who has made it his life's mission to destroy the Man of Steel, Lex Luthor is one of the greatest villains in all of comics. His actions as one of the most brilliant and wealthy men in the DC Universe have caused untold harm to countless people and civilizations, and readers are always excited to see what he does next.

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But with someone as vile as Lex Luthor, it can be hard to keep track of the truly horrific things he has done. From the big events that have put all of existence in danger to the little moments where Lex takes the time to decimate a single person, these are just a few of the cruelest things Lex Luthor has done.

10 Killed His Trainer

Sasha Green Kicks Lex Luthor

When you're as evil and egotistical as Lex Luthor, every embarrassment is a grave offense, and this is a lesson Sasha Green learned the hard way. Sasha was Luthor's martial arts instructor, and she decided to use a moment where Lex was distracted to teach him a lesson about turning away from a foe.

As Lex was caught up in a daydream during his training, Sasha hit him with a kick. Making it worse, she did this in front of Lois Lane. So filled with rage over this small moment, Lex would later kill Sasha by choking her with his bare hands before dumping her body in a landfill.

9 Manipulated The Matrix Supergirl

Supergirl Matrix and Cloned Lex Luthor in DC Comics.

After the events of Crisis on Infinite Earths, the decision was made to keep Superman as the last living Kryptonian for a while, but fans and creators still wanted to see Supergirl, so the teams on the Superman books came up with a solution; a shapeshifting alien that would take on the appearance of Supergirl.

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This version of the Girl of Steel, known as Supergirl Matrix, ended up working with Lex Luthor and even became his lover. Of course, Lex was lying to her the whole time. While Supergirl believed that Lex was a good man and that her work was helping people, in truth, Luthor was using her for his own nefarious purposes.

8 Illegally Used His Powers As President

President Lex Luthor

For a man who desires power as much as Lex Luthor, it seemed only natural that he would try to become the leader of a country sooner or later. What is shocking is that the citizens of the United States in the DCU elected him to be president despite knowing what a horrible person he is.

Lex didn't waste much time using his new power over the most powerful government in the world to carry out his personal goals. As fast as he could, Luthor turned the might of the US military against Superman and Batman after falsifying evidence to show that the two heroes were trying to destroy the world.

7 Destroyed A Waitress' Life

Lex Luthor and the Waitress

Between attempts to kill Superman or become ruler of the world, Lex sometimes likes to mess with a single person just for kicks. One such person was Jenny, a waitress at a diner. Lex offered Jenny a million dollars if she would leave her husband and marry him for just one month, then went out to his limo, giving Jenny ten minutes to decide.

After coming to terms that her marriage wasn't as important as a million dollars to her, Jenny headed out to Lex's limo. Just as she walked outside, the limo drove away. For the rest of her life, Jenny would know that she chose money over love.

6 Destroyed Metropolis For No Reason

The Fall of Metropolis

After his original body was ravaged by cancer thanks to his decision to wear a kryptonite ring all the time, Lex made a clone of himself that was younger and had a full head of long red hair to implant his brain into. In time, that clone body began to deteriorate, and Lex was once again facing death. That, mixed with the knowledge that Lois Lane was about to reveal all his dirty deeds to the world led to Lex doing something that seems out of character for him; he decided to destroy Metropolis. Yes, Lex loved the city that he had come to basically own, but if he was going to die, he felt that he may as well take the town he built with him.

5 Created A Lois Lane Adult Doll

Lex Luthor and a Robot Lois Lane

In the days before Superman came to Metropolis, Lois Lane and Lex Luthor dated. It was never anything serious, and it ended before Lois met Clark Kent, but they were still an item at some point. Having Lois break up with him was something Lex never really got over, and to deal with it in the most creepy way possible, he had a robot of Lois Lane built.

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The robot Lois, made out of the DNA of the real Lois and some Kryptonian tech, not only served as Lex's confidant and bodyguard - her arms could turn into guns - she also served as his lover. Everything about this move by Lex was just gross.

4 Destroyed New Krypton

Superman witnesses Death of New Krypton

Lex claims that his real issue with Superman is that he fears the day the Last Son of Krypton will turn against mankind. This is a feeling that Lex shared with General Sam Lane, the father of Lois and Lucy. When Superman was able to free the shrunken Kryptonians from the Bottle City of Kandor, they set up a home on an artificial planet called New Krypton, and this sent Luthor and General Lane into a frenzy.

Believing that the Kryptonians would surely conquer Earth sooner or later, the two men worked together to end the theorized Kryptonian threat. While General Lane believed that the plan was to just use gold kryptonite to rob the Kryptonians of their powers, Lex had another idea; he used a bomb to destroy New Krypton, killing almost everyone on it.

3 Gave People Powers, Then Killed Them

52 issue 35 Cover

After the events of the Infinite Crisis, the world was left without a Superman, Batman, or Wonder Woman for a year. During this period, Lex took it upon himself to create new superheroes. Using the Everyman Project, Lex held auditions and chose specific people to be powered up and join his own team, the new Infinity Inc.

What these new heroes didn't know was that what Lex Luthor gave them, he could take away, and that is exactly what he did. At first, Lex did it to heroes he didn't like, but in the end, he cut off every hero he created from their powers, killing countless men and women in the process.

2 Paralyzed His Own Sister

Lena Luthor and Lex Luthor in Adventure Comics

Lex doesn't treat his own family any better than he treats others, as his sister Lena can attest. A paraplegic and broke - despite her brother being one of the wealthiest men ever - Lena and her daughter Lori broke into a pharmacy to steal medication that Lena needed to live. They were caught by Superboy, and somehow Lex showed up. Lex revealed that he could cure his sister if Superboy would collect certain hard-to-find ingredients for a serum. Superboy got the needed ingredients and Lex did indeed cure his sister.

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Just as Lena was feeling a sense of joy she hadn't had in ages, Lex injected her with a second serum that once again left her as a paraplegic and made it clear that as long as Superman lives, Lena would never walk.

1 Sold Out Humanity To Perpetua

Perpetua DC Comics

Perhaps the worst thing Lex has ever done on a massive scale was selling out all of existence to Perpetua. With Luthor's help, Perpetua was able to destroy the multiverse she had created, decimating the Justice League in the process and causing the events of Dark Nights: Death Metal. Of course, in Perpetua Luthor met someone even crueler than he was. Perpetua turned on Lex as soon as she had what she wanted, nearly killing him. In the end, Luthor worked with the heroes to save existence, but it is only a matter of time before he gets back to his old tricks.

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