Bruce Banner is The Incredible Hulk. Normally a mild-mannered person, when he is angered he turns into a large green monster.
Joe Pesci played a character in "Goodfellas," a movie about the mafia. In one scene, an underling says that he is "funny" and he famously takes great offense at the notion.
Al Pacino played "Scarface," another organized crime character. His "little friend" is a machine gun, which he uses to put many holes in an adversary, after uttering the line "say hello to my little friend."
Walter White was the humble high school chemistry teacher in the TV series "Breaking Bad," who grows into a meth kingpin.
Tony Soprano was the titular character on "The Sopranos," an HBO series about, you guessed it, mafia gangsters. "Gabagool" is a type of lunchmeat, known in English as "capicola."