Fan Casting Colossal Boy in Return to the DC Universe

Exposure to a radioactive meteorite affected Gim Allon's physiology, allowing him to be able to grow to giant size at will. He used this power with the Science Police, before encouragement from his parents led Gim to use his powers to help more people, which led him to join the Legion of Super-Heroes, with fellow Legionnaire Chameleon Boy (who he gave his codename to), taking on the name "Colossal Boy". While in the Legion, Colossal Boy would remain great friends with Chameleon Boy and go onto also marrying fellow Legionnaire Chameleon Girl.