5) Captain America Superman
While DC have Superman, Marvel have Captain America. Both are the strong-moralled (and muscled) leaders of their respective leagues of heroes. When the two company’s combined forces to create Amalgam Comics in 1996 though, Clark Kent and Steve Rogers were merged into one.
In this unique mash-up, Clark Kent volunteers for an experimental procedure during World War II. After being given a serum derived from alien cells discovered from a crashed spacecraft – plus a boost of solar energy – Kent becomes Super-Soldier, capable of flight, enhanced strength and heat-vision. With his friends Sgt. Rock and his Howling Commandos, Super-Soldier goes up against Lex Luthor AKA Green Skull, the fiendish head of HYDRA.
In case you’re wondering, other mash-ups of Amalgam Comics included Iron Lantern, Bruce Wayne: Agent of S.H.I.E.L.D. and Doctor Strangefate. Super-Soldier was one of the most successful though, as he also nabbed a sequel series, Super-Soldier: Man of War.