Who's This? The Roman-looking guy on page 18 in Who's Who vol. XXI.
How you could have heard of him: He played a bigger part in the best-forgotten War of the Gods mini-series, but it didn't lead to bigger and better things (despite him getting an entry in the 90s loose leaf Who's Who) because he was killed in the last issue. Readers are more likely to remember him as a denizen of Limbo in Grant Morrison's Animal Man. The 2007 Son of Vulcan mini-series is about a different guy entirely, Miguel Devante, who went on to join some iteration of the Teen Titans. And because that franchise is a meat grinder, that version was last seen in a coma.
Example story: Son of Vulcan #49 (1965) by Joe Gill, Bill Fraccio and Tony Tallarico
Our chosen story features return engagements by Son of Vulcan's two archenemies - Dr. Kong, a Fu Manchu type dubbed "the meanest man alive", and Mars, the jealous God of War exiled on Earth by an angry Jupiter. Dr. Kong is planning to steal 2 billion dollars' worth of diamonds from a diamond exchange (eat your heart out, Dr. Evil), and has booked the Chinese theater across the street as a cover for his operation. Following his instincts, journalist Johnny Mann, meant to cover the diamonds' security, takes in a show and decides to head backstage.
It's kind of too bad Son of Vulcan didn't have the kind of impact other Charlton heroes did. As a cross between Captain Marvel and Wonder Woman, with the Olympian Gods a nifty supporting cast, it could have been something. After Crisis, Wonder Woman's own re-connection with these myths made the point moot, I suppose.
Who else? Issues XXI and XXII are so full of Space and Star heroes, it would be a shame not to do at least one.