Killer Croc
This one is mostly about looks, since Killer Croc isn’t renowned for having much between the ears in the first place. Whether he’s hiding in the swamp or sewers, Waylon Jones is to Batman what the Lizard is to Spidey.
The Lizard first appeared in The Amazing Spider-Man #6 back in 1963, while Croc popped up in Detective Comics in 1983. Initially, Jones was shown to be someone born with a form of atavism that gave him a reptilian appearance and traits. Over time, though, he’s become increasingly more bestial in appearance and nature, which is explained as the disease taking over the human side of him.
Nonetheless, it’s obvious where the crux of Croc’s stories come from. Much like the Lizard, it’s the never-ending struggle of finding the balance between the man and monster, with the latter seemingly winning the battle. Mind you, living in a swamp or sewer will do that to a person – just imagine the stench in those places?!