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Mario and Luigi meet up with the almost completely Koopafied Mayor of New York City
The Mayor of New York City is, as his name implies, the mayor of New York City, the original home of Mario and Luigi. The current officeholder in real life is Bill de Blasio.
In The Adventures of Super Mario Bros. 3 episode "Recycled Koopa", Mario and Luigi, believing the Mayor of New York City could help them clean up the garbage Bowser was dumping on Brooklyn, went to the New York City hall to find him. Arriving at the city hall, Mario and Luigi were horrified to find that the mayor, like everyone else nearby, had begun to mutate into a Koopa Zombie, with only his head remaining human. Before Mario or Luigi could speak with the panicking mayor, he fully transformed into a Koopa Zombie and ran into the streets of the city, where he joined a horde of his mindless, Koopa Zombie brethren.