Diamondhead

Diamondhead is a Marvel supervillain whose body is composed of an indestructible diamond-like crystalline substance, making him virtually impervious to physical harm. He is best known as a recurring enemy of Nova (Richard Rider), though he has also clashed with Spider-Man and Captain America.

A crystalline menace born in the Bronze Age, Diamondhead has been a persistent thorn in Marvel's side since his 1979 debut in Spider-Man Comic #323, brought to life by Len Wein and Keith Pollard. Over nearly four decades — a respectable 38-year stretch — this villain has crossed paths with some of Marvel's finest, sharing pages with the likes of Spider-Man, Captain America, and Nova's own Richard Rider. His appearances in the Nova series in particular mark him as a recurring nemesis in that corner of the Marvel universe, and with a key collector issue to his name, Diamondhead is exactly the kind of enduring Bronze Age baddie that rewards the dedicated back-issue hunter.