Killer Croc (The Batman)

History
Killer croc was a kid with a rare disease who was rejected from society so he became a bank robber. He tries to rob all of the banks in downtown Gotham by backing up the sewage pipes that are used to transfer water out from the city. He is stopped just in time by Batman.

Another time, he joins team penguin and is the one that sneaks into facilities using the underwater ways and defeats the guards. He is defeated by Batman.

He was also one of the villains that you got to see get captured by Rumor.