Batman: The Animated Series" Two-Face & Man-Bat" Review

Villians:
Harvey Dent (A.K.A Big Bad Harv A.K.A. Two-Face) is a former District Attorney of Gotham, but now a professional criminal after his career was wrecked by an unfortunate accident.
Scientist Kirk Langstrom worked as a Zoologist at the Gotham City Zoo, experimenting with bat mutagen to create a serum to replicate the creatures' long life. After testing the serum on himself, Langstrom became the vicious Man-Bat.