8) Multiple Man
After retiring from the life of a costumed hero, Jamie Madox – formally known as Multiple Man – started up his own detective agency, X-Factor Investigations (briefly known as XXX Investigations until it was pointed out to him that it sounded like he was investigating porn). With teammates like Strong Guy, Wolfsbane, Siryn and Rictor, Madox helped out his fellow mutants in New York’s Mutant Town district.
As can be deduced from his superhero moniker, Madox can duplicate himself on impact, which is a handy skill to have for a detective as he can chase up several leads at once. This also allows him to effectively have several different lives, meaning he’s acquired valuable skills over time. Jamie Madox is proficient in martial arts, handgun training, picking locks and card throwing. He can also speak multiple languages, has received espionage training, was once an Olympic gymnast and has been a licensed attorney.
In the comics, Madox is currently dead, after he succumbed to the harmful effects of the Terrigen Mists that give Inhumans their powers. In fact, it was his death that sparked the X-Men/Inhuman War.