Lex Luthor and the Joker, as archenemies of Superman and Batman, respectively, are arguably the two most famous DC supervillains. Each personifies evil in the DCU in his own manner, despite the differences in their personalities, skills, and abilities.
Setting aside their personal skills, capabilities, and resources (which would generally greatly favor Luthor), just in terms of their sheer sociopathy, which one poses a bigger menace? In Luthor, we have ruthless, calculating ambition. In Joker, we have homicidal insanity. Which one represents the greater threat to society taken just in terms of their motives and personalities?
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