Superman has faced many enemies during his existence. Lex Luthor is nevertheless the first character that many people remember when they think about Superman's villains. He has been an important part of Superman comics for decades and he also had multiple portrayals in films and on TV. Some of them didn't quite meet the expectations of the viewers though.
That was also the case with Jesse Eisenberg's Lex Luthor in the DCEU who was in many ways different from the traditional comic book portrayal of Luthor. Arrowverse's Jon Cryer who portrays Lex Luthor on Supergirl is seemingly much more closely connected to the comics. However, even DCEU's Lex Luthor is tied to the comics in a way superhero fans might not realize.
Jesse Eisenberg Is Comic Accurate: He Managed To Defeat Superman
Even though some viewers believed Lex Luthor's plan in Batman v Superman: Dawn of Justice (2016) didn't make much sense, it still worked. Lex was able to manipulate Batman and Superman into fighting each other and by creating Doomsday, he did achieve what he had planned to do - to kill Superman. Albeit only for a while.
It wasn't the first time Luthor managed to defeat Superman as he did so in the comics before as well, usually by using Kryptonite against Superman.
Jon Cryer Is Better: He's The Right Age
In the comics, most stories portray Luthor as a middle-aged man, a brilliant genius who's already been through a lot and has a calm and composed demeanor most of the time. That doesn't make him any less dangerous though. Jon Cryer's age, looks, as well as behavior in the role all fit Lex Luthor's persona better than Jesse Eisenberg.
Jesse Eisenberg Is Comic Accurate: He Hates Superman
Of course, Eisenberg's Lex Luthor wouldn't plan to kill Superman if he didn't hate him. From Lex Luthor's point of view, Superman is an unpredictable threat that needs to be stopped. In the comics, Luthor tends to believe that with his considerable powers, Superman could do great damage to Earth and humanity if he ever turned evil. And he's right too.
In the DCEU, Luthor is also skeptical toward Superman in this way which ultimately leads to him coming up with a way how to get rid of the Man of Steel - simply because like his comic book counterpart, he sees Superman as the biggest threat that Earth has ever faced.
Jon Cryer Is Better: He's Even More Successful At His Manipulations
It's true that Luthor's plan in the DCEU led to Superman's temporary defeat. However, it didn't work out the way Lex might have imagined. Not only did Superman come back and join the Justice League but Luthor was also imprisoned. In the Arrowverse, Luthor has successfully managed to manipulate people multiple times, and with a much better overall score.
For example, he manipulated Red Daughter to end up redeeming himself and being seen as a hero by the general public. Or he used the Book of Destiny to rewrite reality and make himself one of the Paragons.
Jesse Eisenberg Is Comic Accurate: Lex Luthor Used To Have Hair
It's a small detail but one the comic book fans might appreciate nonetheless. When someone says "Lex Luthor," most people think of a bald man. But Luthor wasn't always like this. In his younger days and in older comics, he used to have quite a lot of hair. He only lost his hair in the comics during an accident in his lab. Luthor blamed Clark Kent for the loss and grew to resent him.
In the DCEU, Luthor loses his hair in a less dramatic fashion - they shave it off when he's imprisoned - but that doesn't change the fact it marks his transformation to the bald villain the fans have grown to like.
Jon Cryer Is Better: He Works With The Heroes Sometimes
Lex Luthor is no fan of superheroes, as he demonstrated multiple times. However, what makes Cryer's Luthor different from Eisenberg's is the fact that he doesn't let his negative feelings toward superheroes cloud his judgment. That means that he occasionally works alongside them, not against them.
It happened during the Arrowverse crossover Crisis on Infinite Earths. As stated above, Luthor first rewrote reality and made himself a Paragon. He then used his intelligence to fight alongside the heroes and even though Supergirl wasn't thrilled with having him on the team, he still helped the superheroes defeat the Anti-Monitor and restore the universe.
Jesse Eisenberg Is Comic Accurate: An Eccentric Young Genius
What some viewers might not know that Jesse Eisenberg is close to a different portrayal of Luthor in the comics. The Lex Luthor most people know looks and behaves in a different way.
But there's also the fact that when Lex Luthor first appeared in the comics, he was an eccentric scientist with hair, not the bald stoic logical man he later became. Eisenberg's Luthor is much more similar to the older version of Lex Luthor.
Jon Cryer Is Better: He Was Once Friends With Superman
Batman v Superman didn't have much time to show Luthor's background. But considering his age and demeanor, it's clear he and Superman were never close. That isn't the case in the Arrowverse. Supergirl didn't portray it in great detail, but it still revealed that just like in some versions of the comics, Clark Kent and Lex Luthor were friends when they were younger.
They even worked side by side to stop an alien invasion on Earth. However, Superman didn't like Luthor's preference for violence, and Luthor, in return, started hating Superman for being so popular and in the end decided to ruin his former friend.
Jesse Eisenberg Is Comic Accurate: He Works With Mercy Graves
Lex Luthor is a genius and it would be understandable to presume he works fine on his own. But even Lex employs other people. In the comics, Mercy Graves works as his bodyguard and she has the same position in the DCEU.
She was originally an Amazonian in disguise but the comics later changed her character and made her Lex Luthor's assistant. Even though Mercy also appeared in the Arrowverse, her character was changed there and the DCEU version is closer to the comics.
Jon Cryer Is Better: He Draws His Plans From The Comic Books
Lex Luthor's storylines on Supergirl were much more closely inspired by his plans in the comics. For example, in both instances, Luthor found out he got cancer after he had injected himself with Kryptonite in order to stop Superman from getting close to him. In the comics, he didn't inject himself, only wore a ring made of Kryptonite but also got sick with cancer.
What the Arrowverse Lex also shares with his comic book counterpart is that he turned the sunlight red at one point because he wanted to deprive Superman of his powers.