10 Most Stupidly-Overpowered Superheroes In Comics History
4. Captain Atom
With invulnerability to most attacks, regeneration abilities, an ability to interface with technology, and all the super-abilities you'd expect from any overpowered character, Captain Atom is the most interesting and overpowered character to be basically forgotten about in the current DC universe.
Atom featured in Infinite Crisis, the One Year Later storyline, and many other iconic DC titles - although the only time he featured in them as a main character was during his time as a villain named Monarch, which would ultimately turn out to be out of the heroes control when he was corrupted by Monitor Solomon during a fight.
In the current universe, Atom barely features in it, despite being one of the most powerful heroes within the universe. While the in-universe excuse is because Captain Atom is too powerful and therefore too volatile, it also seems pretty likely that he's simply too powerful to include in any fights, as it would immediately make the whole thing less interesting.
All this does reaffirm why overpowered superheroes and so few and frequent nowadays - because they just don't become as popular.