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Billed as the “Hero and Villain in One Man,” Eclipso debuted in DC Comics' The House of Secrets #61 (1963). “The Genius Who Fought Himself!” by Bob Haney and Lee Elias introduced solar physicist Dr. Bruce Gordon, architect of Solar City, a prototypical sun-powered municipality. As a solar eclipse occurs, an ominous pale-blue shadow magically appears over half of the doctor's face, and “that fool Bruce Gordon” transmogrifies into the evil Eclipso. In an ensemble of black and purple with a lunar/solar eclipse emblem, Eclipso, exhibiting superstrength and stamina, decimates Solar City with a devastating dark-light beam projected through a black diamond he holds to his “eclipsed” eye. Possessed of Eclipso's dark spirit from an earlier expedition to Diablo Island in the South Pacific, the heroic Gordon struggled against the demon within in House of Secrets for three years, with Gordon's ally Professor Simon Bennett and his daughter Mona (Bruce's girlfriend) returning Eclipso to dormancy by exposing him to his one weakness—light. Eclipso's potency as a villain was often weakened by stories that depicted him succumbing to light sources as bland as camera flashes. Nonetheless, he returned for decades in various DC series, battling Batman, the Justice League, Green Lantern, the Metal Men, the Phantom Stranger, and other heroes. Eclipso's true nature was revealed in Eclipso: The Darkness Within #1 (1992), a giant-sized comic inaugurating a crossover that crept through DC's various summer annuals; a variant edition of issue #1's cover featured a Bart Sears–drawn close-up of Eclipso holding a “real” (plastic) black diamond to his eye. Readers discovered that Eclipso was actually the primeval god of vengeance, a role later served by the Spectre. Eclipso was once imprisoned inside a giant black gem called the Heart of Darkness (a deliberate nod to author Joseph Conrad's tale of the same name), but in the late nineteenth century a jeweler chiseled the stone into a thousand pieces that were dispersed across the globe. Eclipso could corrupt anyone holding one of the diamond fragments once that host succumbed to rage. Throughout the Darkness Within crossover, various DC superheroes found themselves “eclipsed” by Eclipso, and the villain spun off into his own monthly series, which ran eighteen issues from 1992 to 1994. Throughout these and subsequent stories, Eclipso has embarked upon the baleful mission of subjugating Earth into darkness, employing various human and superhuman vessels in his chaotic quest. Bruce Gordon was ultimately freed of Eclipso's influence, and this nocturnal nemesis has become one of the most bloodthirsty menaces in the DC Universe, slaughtering several minor superheroes and countless civilians. For a brief time Eclipso fell under the control of the brother of one of the heroes he murdered, but has since broken free. He once again ascended into prominence in 2005, first possessing Superman, leading to a clash of titans between Captain Marvel and the eclipsed Man of Steel, and later spreading his demonic influence upon Jean Loring, the criminally insane ex-wife of the Atom. As the new Eclipso, Loring allied with the Spectre in the miniseries Day of Vengeance (2005), partnering to eliminate magic from Earth. Now a creature of unadulterated evil, Eclipso's roots as the villain who cowered from flashlights are long forgotten.