The X-Men #55

A glowing, arms-wide green figure dominates this April 1969 cover as the entire X-Men team — Marvel Girl, Iceman, Angel, Cyclops, and a red-clad figure — reels around him in a burst of fiery orange energy. The sheer scale of that central threat sets an urgent, dramatic tone that perfectly matches the promise of "The Living Pharaoh!" Roy Thomas writes the interior, with cover pencils by Barry Windsor-Smith and inks by Vince Colletta lending the image a striking boldness. It's a vivid snapshot of late-'60s Marvel at full throttle.