Steve Armstrong is an Earthling who gained fame as a professional Arena fighter. Before that, he worked as a cook in a small space station diner. After picking up a fight with an alien Arena combatant named Fang and winning, Armstrong caught the eye of Fang's manager, Quinn, who offered him a chance to try out his skills in the Arena.
Armstrong initially refused. Even though the fight with Fang caused him and his friend Shorty to lose their jobs at the diner, he wanted nothing more than to make his way back to his native Earth.
Armstrong only agreed to become a fighter after Shorty was threatened by the crime boss Rogor, who he was indebted to. By accepting Quinn's offer, Steve got enough money to pay off Rogor and eventually became the first Human Arena champion in decades.