After his father dies in a gangland slaying, a young man decides to battle the killers in style. Travelling around the world studying weaponry, he becomes an expert at the use of every type of arms imaginable, then turns his expertise against the mob.
The Challenger time-traveled to the present in the pages of She-Hulk, after which he apparently joined the Initiative and was assigned to Montana and Freedom Force.
The Challenger only has one superhuman power: the power to suppress pain at will.
He is very skilled in hand-to-hand combat and most conventional weapons, a very skilled marksman, knows many languages, adept in chemistry and knows how to drive a plane.