Replying...
Intro. Killer croc formerly known or rather whose real name is Waylon Jones, does not transform in the traditional sense, but rather suffers from a mutation or genetic disease that makes him look like a reptile, his appearance "transformation" is due to an extreme form of the medical condition known as epidermolytic hyperkeratosis. This skin disease causes his appearance to develop progressively, which gives him an appearance of scales and thick or hard green or gray skin, superhuman strength, resistance and speed, sharp, crowded and slightly deformed claws and teeth of different thicknesses, with a highly developed sense of smell, he has a huge crocodile or alligator tail, his scales as hard as steel, a well-known villain from Gotham and especially Batman, not to mention his enormous mouth since his condition is progressively worsening.

Killer croc

@Unknown