Ryan Meinerding has spent the last few months reliving his years in the Marvel Cinematic Universe on his Facebook page. If you don't know what role Meinderding played in films like "Iron Man" and "The Avengers," it's okay; you didn't miss some secret character connecting all the films in the background.
Instead, Meinerding had a hand in designing many of the iconic characters and scenes in those films on the backend. He's a conceptual artist, and he's been releasing a whole bunch of artwork from his time working on everything from "Captain America: The First Avenger," to "Iron Man 3," to "Avengers: Age of Ultron."
Below, see his early design work for characters like Iron Man's Mark 1, 43, and 45 armor; Tony Stark's garage boot test; Captain America's WWII costume; "Iron Man 2's" War Machine; "Iron Man 3's" The Mandarin/Trevor Slattery; and The Vision. Hat tip to ComicBook.com for the source.