Thanks to Tony Stark's Hall of Armour, Iron Man 3 saw the hero bring hundreds of alternate costumes to give him a helping hand during his battle with A.I.M.'s Aldrich Killian. Ultimately, they were all blown up, but their legacy lives on...through some very expensive Hot Toys action figures!
Recently, Marvel Studios concept artist Andy Park revealed that he had picked up Mark XVI replica, and later shared some concept art revealing his initial design for the armour.
As you can see, he explains that the colour was changed in the movie because the final battle took place at night. Grey and black would have been harder to see than red and gold, though it could also be because this suit closely resembles War Machine's recognisable colour scheme.
Check out Park's Iron Man 3 Instagram posts below: