The Joker, the Penguin, the Riddler, Harley Quinn, Scarecrow, Mr. Freeze. Batman has always had the most compelling set of criminals for our hero to fight against — and if you look at them all as a group, the reason why they’re so much more interesting than any other villains out there becomes pretty clear.
In response to a post on the history of the Joker, a discussion kicked off over why the character had kept going for so long. Commenter TRT-X pointed out that “what has made Joker such a great villain is that he, like Batman, is just a guy. So when he decides to go up against Batman, you get the impression it’s because he’s truly confident in his plans/skills. Turning him into a super-villain would make him far less interesting.”
Perhaps — but it’s not just the Joker. When you look a little closer, it’s pretty clear that there’s a similar strain running all through Gotham City.
Batman himself has always been a well-known outlier among superheroes. Unlike his contemporaries — whose spec sheets include things like “eye lasers” or “human flight”— his own special skillset is comparatively earthbound. He’s exceptionally strong, but within human parameters. He’s extremely clever, but his mind is not a computer. He’s wealthy and technologically adept, but the tools of his trade are mostly things that you might plausibly see in a test lab. Basically, much of the appeal of Batman is that, unlike other superheroes, he’s simply a person who has pushed himself to the edge of his natural limits.
The flipside of that, though, is that (with a few notable exceptions that veer into the supernatural) the villains he faces are also by and large simply people with a single, notable obsession — and that’s why they’re so much more interesting than the usual set of villains. When a supervillain or superhero origin story is told, it’s usually just an accounting of whatever accidents lined up to give them their strange new powers. In Batman, origin stories tend to be about fixations that overtake that character’s life, whether that fixation is retribution (Batman), botany (Poison Ivy), or the randomness of life (Harvey Dent).
In Gotham, it’s not radioactive spiderbites, or a cosmic ray blast to a spaceship, or the sun of a distant planet that confers power; it’s simply the slow, continuous application of time. Time spent obsessively perfecting your ability to launch a bat-shaped throwing star with pinpoint accuracy or (in a much less altruistic example) building an elaborate, riddle-controlled labyrith, in which to trap your enemies. Because in Batman, obsession is the only real superpower.