Ghost is the perfect enemy for someone like Iron Man. In a tragic event which led to the murder of his wife, Ghost spiraled into depression. His seething rage led him to develop a state-of-the-art suit made of GhostChips, which he previously made for the company he used to work for. It was also the same company which killed his wife because she was going to reveal that her superiors forced her to be a call girl.
In ‘The Big Bang Theory’ arc, Ghost was hired by A.I.M. to dismantle companies like Roxxon and Stark Industries. But at the same time, Tony Stark had infiltrated A.I.M. only to be found by Ghost. Ghost made sure to give Tony an ass kicking of a lifetime, and even managed to escape without any damage.
Erik Lehnsherr, or more commonly known as Magneto is one of the strongest mutants in the Marvel Universe. Having a total control over magnetism, Magneto is a force of nature.
Though Iron Man has certain suits which are immune to Magneto’s abilities, most of the times, he fails to estimate Magneto’s real power. Just to put it in perspective, in X2, Magneto was able to rip the iron straight out of someone’s bloodstream. If that didn’t impress you, Magneto once deflected a bullet in outer space, while still on Earth.
In his first fight with Iron Man, Magneto mercilessly beats him, leaving no space for any witty maneuver. Then again, Magneto has defeated both Iron Man and War Machine simultaneously, proving his superiority in style.