Although the Hulk is without question the main antagonist of his book,Storytelling 101 generally recommends that any fictional hero have a cast of supporting characters around them that are equally as compelling as the central character. The Hulk, a somewhat heavy-handed commentary on the negative effects of arouse on a human body, or has Rick Jones,a hipster that wanders onto a test site and causes scientist Bruce Banner's transformation into the Hulk when he leaps in to save Rick from being bombarded by gamma radiation.
Source: blastr.com