Strong Guy is a very complex, overlooked and simple character all at the same time. How does that make any sense?
Strong Guy’s power is that he is able to transform the energy from a physical impact into muscle mass, turning his physique into something that a strong man participant could only dream of. That said, Strong Guy isn’t a strong man at heart. Instead, he’s just projecting a large wise cracking, musclebound image.
We learned in X-Factor #87 about his childhood, with him being a constantly bullied, nerdy weakling who covered up his insecurities with a lot of sarcasm. Once his mutant powers kicked in, he still never developed his confidence. He’s spent a fortune trying to impress people and is severely afraid of letting people know that his mutation causes him a lot of pain.
That said, Strong Guy makes a strong supporting character, whether he is a bodyguard for Lila Cheney or Dazzler or a member of the various X-Factor incarnations he has been part of. Strong Guy works so well in the X-Universe because of his dual nature. He loves putting out the image of a tough guy smart ass, like a WWE version of Denis Leary. But his true self, the one all his teammates and friends see, is a very kind and gregarious giant.