While Avengers 4 will be unlike any Marvel Cinematic Universe movie that's come before, there will be a few traditional staples that Marvel fans know and appreciate. One staple that goes all the way back to the MCU's humble beginnings is no doubt the regular upgrades in Tony Stark's Iron Man armor.
Already there's been some supposedly leaked Iron Man armor concept art for Avengers 4, which hints that Tony could be going with a classic "gold sleeves" look with his next phase of armor. Well, some Avengers: Infinity War concept art by artist Daren Horley may reveal a bit more of how Tony Stark's Avengers 4 armor functions:
The images above are designated to be Tony's "undersuit" for this version of the Iron Man armor, and there's speculation that the sleeving effect for the suit could come with an effects process like the one seen above - and the same goes for the helmet. It would make a certain amount of sense, as Tony was seen having cracked nanotech applications for his armor in Avengers: Infinity War, and this design simply looks like a more advanced version of that - or at least, one that's depicted in more intricate detail, using more detailed and sophisticated visual effects to show the armor "growing" over Tony in different ways, as he literally builds new tech on a whim.
It's a similar effect to what we saw from the '90s Spawn movie, with its "living mask" and costume effects. Given that Avengers 4 is expected to take the original Avengers team (plus a few others) on a journey through space and time, it would make sense for Tony to have an armor that can manifest different levels of coverage, for the extreme changes in environment that Tony might experience. The golden sleeve look is something that we got with the Silver Age Iron Man comics, and one of the few looks that hasn't gotten strong representation in the MCU movies. It would be a fun twist to have one of Tony's earliest designs become the basis for what could be his final outing as Iron Man. After all, many of the original Avengers are expected to be rebooted after Avengers 4, so this would be a nice swan song that longtime Marvel Comics fans would appreciate.
Avengers: Infinity War is now available as a digital download and on Blu-ray and DVD. Upcoming Marvel Cinematic Universe movies include Captain Marvel on March 8, 2019, Avengers 4 on May 3, 2019, and Spider-Man: Far From Home on July 5, 2019.