Whenever you think “Hulk,” you think green. The two are intrinsically linked. Yet, when the Hulk first appeared in 1963, he was actually meant to be gray. However, due to the fact the printer couldn’t provide a consistent gray color, the Hulk would change from gray to black to other shades of gray from page to page and panel to panel. In order to address the issue, Stan Lee choose to go with a color that would come off the printing press with fewer issues: the now-iconic green.