That’s not satisfying enough for the audience. We need prime Iron Man, which complicates things, as Marvel wants its Endgame finale unharmed. Thankfully, Marvel has a time travel machine ...

Narrator: If you look at Iron Man's first suit, the Mark 1, and compare it to the hero's nanotech suit from "Avengers: Endgame," a lot has changed. But it's not just the technology in the world of ...