10 Times Lex Luthor Outsmarted Everyone
3. When He Destroyed New Krypton
In the "New Krypton" crossover storyline, Superman finally managed to save the inhabitants of the Kryptonian city of Kandor from Brainiac. Using Kryptonian technology, the city's residents created a crystalline planet, which was placed in the opposing orbit of Earth, keeping the Sun between them as they went about their orbits.
The new world was dubbed New Krypton, and Superman decided to live there with his people instead of remaining on Earth. Eventually, General Zod did what he does best, and he planned an attack on Earth from New Krypton. Learning this, Lex Luthor, Reactron, and Metallo attacked the city.
Before the battle, Lex managed to alter Reactron's body chemistry, causing him to explode in a chain reaction that utterly destroyed New Krypton. Nearly all of the city's inhabitants were killed in the devastation, which essentially means, Lex Luthor successfully destroyed a planet filled with people as powerful as Superman.
The impact of destroying New Krypton was significant and resulted in a full declaration of war by General Zod against the people of Earth. Granted, he was planning on doing this anyway, but Luthor's accomplishment in destroying a newly-formed Krypton and its residents to protect Earth is no small feat.