Hulk

During a gamma bomb test he himself designed, brilliant nuclear physicist Dr. Bruce Banner rushed onto the test range to push a young civilian to safety — absorbing a massive burst of gamma radiation in the process. The exposure transformed him, causing him to periodically become the Hulk: an enormous, superhumanly powerful green-skinned brute whose strength grows with his rage.

Few characters in Marvel's vast cosmos hit as hard as the Hulk — a Silver Age titan born in the pages of The Incredible Hulk #1 in 1962, conjured by the legendary partnership of Stan Lee and Jack Kirby at the very moment Marvel was rewriting what superhero comics could be. Over 64 years and more than 2,300 catalogued appearances — 113 of them recognized as key collector issues — he has proven himself one of the most enduring and complex figures the medium has ever produced. His longest haunts are the pages of The Incredible Hulk and The Defenders, where he shares adventures with some of Marvel's greatest: Spider-Man, Captain America, Iron Man, and the alter egos behind those masks. If you're building any serious Marvel collection, the Hulk isn't just a character you encounter — he's a cornerstone you keep coming back to.