Jack Winters

Jack Winters, known as the Jack O'Diamonds, is a mutant criminal with the ability to transform his body into living diamond and project destructive energy. He attempted to exploit a young Scott Summers for his own ends, inadvertently setting Cyclops on the path to joining the X-Men.

Roy Thomas and Don Heck introduced Jack Winters to Marvel readers in 1967's The X-Men #39, making him a genuine Silver Age artifact from one of comics' most beloved franchises. His debut issue carries collector-significant key status, and he shares those early pages with heavy hitters like Cyclops, Iceman, and Charles Xavier himself — rarefied company for any character stepping onto the Marvel stage. Though his catalog footprint is modest, his appearances stretch across an impressive span of decades, turning up in X-Men Legends and the archival Marvel Masterworks alongside his original run — a sign that fans and editors alike have found him worth revisiting. For collectors hunting the deep corners of Silver Age X-Men history, Jack Winters is exactly the kind of discovery that makes the back-issue hunt worthwhile.