The self-proclaimed "greatest criminal mind of out time".
As part of the continuity changes which followed The Man of Steel and Superman: Secret Origin, Luthor is shown actively participating in the creation of three Superman villains, Parasite (indirectly), Bizarro (the failed result of an attempt to clone Superman), and the cyborg Metallo. Upon discovering that Metallo is powered by a 'heart' of kryptonite rock in Superman (vol. 2) #2, Luthor steals it in order to fashion a kryptonite ring for himself. He wears the alien ore around his finger as a symbol that he is untouchable, even to the Man of Steel, after carrying out a series of kidnappings to try to determine the nature of the connection between Superman and Clark Kent. Although computer analysis of the assembled data revealed that Clark Kent and Superman were the same person, Luthor dismissed the results because he believed that he 'knew' that someone as powerful as Superman would never choose to live a normal human life.
As the JokerEditIn Speeding Bullets, Lex Luthor was horrifically transformed when he got into a disfiguring accident that turned him into the Joker. He kidnaps Lois Lane. She is rescued while he is defeated by the Batman.
One day, a group of robbers invaded his house. Bruce uses his powers to brutally attack the robbers, tearing them apart with his heat vision. He decides there is much he can do with his powers. He takes up the identity of the Batman. Bruce also takes up a job as publisher at the "Planet" which was bought by Lexcorp.
One day, when Lois was kicked out of Lex's Limo and was about to be attacked by a group of thugs, the "Batman" steps in and breaks them apart, he burns their flesh, splinters their bones. He was a dangerous psychopathic animal.
After Lex Luthor supposedly died in a flood of chemicals and flames, he was reborn as the Joker. He kidnaps Lois and flies away with her. He reveals his plan to take over Gotham and begins his attack. The Joker commands his mercenary army -- supplied with guns, grenades, fire-bombs and everything else Lexcorp money could buy. He intended to take control of the city and remake it in his own warped design.
Relationship with the JokerEditJoker often acts friendly with Luthor, who is usually just annoyed by Joker's antics. That said, Joker is probably the closest thing Luthor has to a friend.
In JLA, Luthor (alongside Joker and Cheetah III) gathers together a new "Injustice League" and, outfitted in a new version of his warsuit, sets out to destroy the Justice League with them. On a related note during this section, he was responsible for creating the third Shaggy Man and the third Blockbuster.
Luthor plays a large role in the Countdown to Final Crisis tie-in event, Salvation Run. Having been sent to the prison planet after his Injustice League was defeated, Lex quickly assumes control of the amassed villains, receiving competition only from Joker and Gorilla Grodd, who convince half of the villains to join them. He does fight the Joker until the battle was interrupted by an attack by Desaad's Parademons. After the attack, Luthor manages to get the villains off the planet with a makeshift teleporter, secretly powered by Neutron, Heatmonger, Plasmus, Warp, and Thunder and Lightning. When called a "monster" by Thunder, Luthor claims it is the ones who sent them there who are the real monsters, and that he is the hero. He later sets the teleporter to self-destruct after he uses it, killing the attacking Parademons, and his living batteries.