Eclipso's early comics debut is tied to his first modern host, Bruce Gordon (named after Bruce Wayne and Commissioner Gordon as an inside joke), a scientist specializing in solar energy. While in the jungle to view a solar eclipse, Gordon was attacked by a tribal sorcerer named Mophir. Before plunging to his death off a cliff, Mophir wounded Gordon with a black diamond. Afterwards, Gordon transformed into the villainous Eclipso whenever an eclipse occurred. A blue-gray or purple circle covered the rightmost two-thirds of his face, resembling a partial eclipse. Gordon experienced many Jekyll-and-Hyde transformations and misadventures in "House of Secrets". During this period, Eclipso was portrayed as a conventional villain, possessing super strength, partial invulnerability, and eye blasts (aided by his black diamond). Eclipso's transformations were later altered so that any type of natural eclipse, lunar or solar, would cause Eclipso and Gordon to split from one another, while an "artificial eclipse" -- an object blocking out a light source -- would merely transform Gordon to Eclipso. Any bright flash of light would banish Eclipso back into Bruce Gordon's body or reverse the change.