Baron Zemo

Few villains carry the weight of history quite like Baron Zemo — a Silver Age antagonist who burst onto the scene in The Avengers #4 in 1964, conjured by the legendary duo of Stan Lee and Jack Kirby at the height of Marvel's creative explosion. Across six decades of comics, from 1964 all the way through 2024, Zemo has haunted the pages of Captain America, The Avengers, and beyond, racking up 113 catalog appearances and an impressive 12 key issues that any serious collector will want on their shelf. He keeps genuinely august company — Iron Man, Thor, the Wasp, and Hank Pym have all shared pages with him — and his deep ties to the Avengers make him one of Marvel's most enduring and consequential figures. If you're building a reading list around the great Marvel antagonists who shaped the Silver Age and never stopped mattering, Baron Zemo is absolutely essential.