Don Vizioso is the gluttonous boss of the Italian Mafia in New York City.
Casey Jones VS. The Underworld - The Shredder meets with him at his restaurant where Don Vizioso is eating spaghetti and meatballs. The Shredder mentions to Vizioso that the power in the Manhattan underworld has shifted to the Foot Clan causing Tiger Claw, Fishface, and the Fulci Twins to prepare to attack each other. Both sides stand down as Vizioso asks Shredder to explain what he means by the power shifting to the Foot Clan. After mentioning how he controls the Russian Mob through Rocksteady, the Purple Dragons and other Asian gangs through Hun, and the South American gangs through Fishface, Shredder proves his point by slicing the candles and the meatball on his fork. This convinces Vizioso to swear his allegiance to him.
Meet Mondo Gecko - Don Vizioso was seen amongst the audience of villains watching Fishface's race against Mikey, Casey, and Mondo Gecko. He was shown eating different foods.
Mutant Gangland - With Shredder and his forces having left Manhattan and considering his alliance with them dissolved, Vizioso begins work to have his Mafiosi wipe Manhattan clean of mutants, including the Mighty Mutanimals and the Turtles, so his Mafia become top dogs in the criminal underworld again. After he has some of his Mafiosi rob a bank to lure out Donatello, Raphael, and Mondo Gecko, he launches a trap that leads to Raphael being badly beaten, while Donatello and Mondo are captured. When confronted by Leonardo, Mikey, Slash, Rockwell, and Leatherhead in his restaurant, Vizioso is able to escape to his second hideout in a hotel, where he decides to have Donatello and Mondo dissected to see how they work once Dr. Farrell shows up. However, the hotel is besieged by the Turtles and Mutanimals, and while the Mutanimals deal with The Hammer and the Mafiosi guards outside, the Turtles deal with confronting Vizioso and the Fulci Twins. In the end, Vizioso is defeated and sent flying away on his hoverchair.
Heart of Evil - After Super Shredder's demise, Vizioso has claimed the Shredder's charred mutant heart as a trophy, planning on eating it to attain the Shredder's power through his spirit in the heart. However, his restaurant is besieged by Leonardo, Donatello, Rocksteady, and Bebop, leading to a fight that results in Vizioso managing to escape on his hoverchair with the heart while his Mafiosi force the two Turtle brothers and Tiger Claw's men to retreat. Having retreated back to his hotel safehouse, Vizioso plans on fleeing the United States until things calm down, but the hotel is attacked by Tiger Claw, Kavaxas, Bebop, and Rocksteady, with Kavaxas easily overpowering Vizioso's men, including his muscle, The Hammer, and draining The Hammer's soul, due to their anti-mutant weapons having no effect on the demon. Vizioso is soon confronted by Leo and Donnie, who overpower the Fulci Twins before Donnie turns his attention to Vizioso. Though Donatello nearly takes Vizioso's life out of personal revenge, he is able to come to his senses and instead takes back the Shredder's heart, only to lose it to Kavaxas and Tiger Claw, while Vizioso, the Fulci Twins, and their Mafiosi are left to be arrested by the NYPD and taken to prison, delivering a crippling blow to the Italian Mafia's presence in NYC.
Don Vizioso has a classic-style painting of himself hanging on the wall above his table in his restaurant.