Michael O'Brien

A former police officer, Michael O'Brien acquired the Guardsman battle suit originally worn by his brother Kevin to investigate Kevin's mysterious death at Stark Industries, putting him on a collision course with Iron Man.

Bronze Age Marvel has no shortage of characters who quietly accumulate decades of story, and Michael O'Brien is a satisfying example — debuting in Iron Man #104 in 1977 courtesy of Sal Buscema, and still turning up in the catalog nearly fifty years later. His team affiliations span an impressive and eclectic range — the Avengers, Alpha Flight, and the Soviet Super Soldiers — hinting at a character whose loyalties and adventures have taken him across very different corners of the Marvel Universe. You'll find him most at home in the pages of Captain America, The Avengers, and Quasar, sharing those adventures with luminaries like Steve Rogers, Wendell Vaughn, and Peggy Carter. With a key issue to his name and nearly five decades of appearances, O'Brien is exactly the kind of deep-catalog figure that rewards the curious collector willing to dig a little deeper.