Iron Man, Vol. 1

Iron Man and Doom have been summoned by Merlin to the year 2093, where he and a (very) young reincarnated Arthur Pendragon have to protect Camelot from an unknown threat. All that is known for sure is that various scientists have been vanishing, and old Star Wars satellites are attacking. Stark investigates directly, and learns that his great grandson has upgraded both the satellites and the Iron Man armour. Doom learns that he is unable to travel back in time with the weapons available in the time period, so he reluctantly joins the forces of good. It is discovered that Doom is still alive, in a fashion, and that the kidnapped individuals are meant to be his servants in this new time, as part of his latest plot to rule the world. (Those who aren't captured are to be killed.) Doom kills his future self, while Iron Man defeats his decendant in a non-lethal manner. Both are returned to their own time, by magic which prevents them from bringing back anything they didn't bring with them, including Doom's knowledge of the man under the Iron Man mask. The artifact does not return with them, so they grudgingly go their separate ways, as they no longer have reason to fight.