Lots of superheroes are “children of the atom” in the sense that they derive powers from some sort of radioactivity (think Spiderman or Hulk or even Daredevil) while others are just born with powers without explanation (X-Men, Thor, Superman, Aquaman, Wonder Woman).
Who is a superhero that is somehow grounded in reality, meaning that they could “potentially” make sense (either their origin story is believable, even if it has some obvious gap to make a super power happen, or their power is somehow limited or constructed in a “reasonable” way).
I guess with these restrictions, Batman would be OK since he’s got no superpowers, but he’s insanely rich and therefore can both train himself and have access to sophisticated gadgets, but can you think of less obvious ones (even if they’re minor characters)?
Thanks for reading this!
Edit: thanks for all the answers and apologies for the slow replies. I’ve had a couple of complicated days. I’ll now go through answering you. Several people made me realize I hadn’t been precise in what I meant and helped with their answers. I was looking for superheroes or superpowers that are somehow “believable” in that they’re either constructed in an unexpected way or in a way that you could almost accept as plausible
Jack Knight Starman. His dad was the OG Starman back in the 40s and invented a Cosmic Staff and Gravity Rod to give himself Green Lantern style super-powers.
Jack’s brother, David, becomes the new Starman using his dad’s costume and tools, Jack wants no part of it, preferring to run an antique shop.
David is killed, their dad is nearly killed, an attempt is made on Jack that he only survives because he had one of his dad’s Cosmic Rods stashed in a closet somewhere.
So, Jack begrudgingly becomes Starman to save his dad and avenge his brother.
That’s a great and involved origin story. Jack takes the mantle though he wants no part in it and becomes a superhero to protect and avenge his family.
It’s interesting to have superheroes who are born out of revenge, like the Punisher mentioned in another comment. I guess revenge is also part of the Spiderman lore, though it isn’t involved in what makes him Spiderman in the first place (and also isn’t shown acting out of rage, like the Punisher).
I admit to not knowing Starman enough so I don’t know if he’s shown acting out of rage (like the Punisher) or of justice (like Spiderman)