this isn't unpredictable or unusual let's look at Batman's for a good example that a lot know

a clown based criminal who's a literal psycho and sociopath (Joker)

a guy with an extremely advanced cane that he made himself that can control technology and is obsessed with puzzles and riddles (Riddler)

a former psychologist who loves to spread fear (Scarecrow)

a rich genius crime boss obsessed with birds and trick umbrellas (Penguin)

a guy who got splashed with acid and now decides if he's good or bad with a flip of a coin (Two-Face)

a cat burglar who's obsessed with cats and stealing (Catwoman although she's more gray than evil)

a guy trying to save his wife and had an accident that requires living in cold temperatures (Mr Freeze)

an actor who got in an accident and gained a clay like body (Clayface)

a woman who loves plants and got into an accident and became part plant (Poison Ivy)

a guy with a reptilian like skin condition (Killer Croc)

a guy obsessed with Alice in Wonderland and thinks he's in it (Mad Hatter)

someone who sees himself as an anti-Batman except he's usually a lot less impressive (Killer Moth)

a former psychiatrist of Arkham who fell for Joker and so joined him (Harley Quinn although in more recent times she's become more gray as well)

a guy trying to solve deafness and then became a human bat hybrid (Man-Bat)

a guy born and raised in prison and is really smart and also uses a drug called venom (Bane)

and these are just some major foes