Vince Dio was Jackie Dio
's little brother. Growing up, Jackie swore to his Father that he would look after Vince. After Vince crossed Jackie, Jackie was about to execute Vince, but decided instead to give him a pass and told him to get out of New York
. This was a bad move on Jackie's part however as Vince turned around and set Jackie up, calling the cops and having them wait where Jackie was going to be. After a brief skirmish, Jackie was able to take out all of the cops and was about to finish what he started earlier with Vince when Spider-Man
showed up and apprehended Jackie, saving Vince's life. While Jackie was locked up, Vince took it upon himself to climb the criminal ladder through enhancements. With enhanced strength, invulnerable skin, and superior reflexes, Vince quickly rose to prominence as the main capo to one of the bosses who stepped in once the Kingpin
was locked up:The Owl
. He renamed himself Mr.Pain and quickly developed a reputation, even having an entire wing of a hospital full of victims of his beatings. Once Jackie got out of prison, he immediately went back to looking for work in the criminal game. An old friend told him to look up the Owl, who was now a top boss. Jackie, not knowing that his brother Vince had been transformed into a hulking enforcer for the Owl, had a confrontation with Vince, and was quickly beaten soundly. In a twist of fate, Vince gave Jackie the same speech about vacating New York as Jackie had done to him years earlier. He then sent him to the hospital, where Jackie was told to look up the consultant for help. After going through a few modifications of his own, Jackie is transformed into the super-villain Underworld. After he soundly beat two of Mr.Pain's henchmen( Grizzly
), he is able to draw out Vince in a final confrontation. After a brief battle, Underworld is able to get the drop on Mr.Pain and puts a bullet into his head, killing him instantly.