He is also known as “Mink”.
In Thanksgiving dinner he prepared explosives in a present box for Harvey Dent. The box was sent to Dent’s home in Gotham City and he exploded when he received orders. Harvey Dent and her wife Gilda Dent were inside.
Mickey manages a little band called “The Irish”.
He was staying in a motel in Gotham City.but Batman went for him. He tried escaping and he went to sewage system but he found first Solomon Grundy and was knocked out. Batman captured and he was interrogated by Batman and comissioner James Gordon.
Finally he and all members of his little gang were killed by the Holiday Killer aka Alberto Falcone before he could testify against his father,Carmine Falcone.