Captain America: Civil War was full of references and Easter Eggs, in addition to being a fun, action-packed film that also managed to carry a strong plot. Overall, it was a fantastic film and it took me two times through to catch one creepy looking Easter Egg.
Warning: The following contains a MAJOR spoiler for Captain America: Civil War. Let the trailer for the movie block you from potential spoilers coming up.
Though he wasn't necessarily villainous, Tony Stark was, without a doubt, an antagonist in Captain America: Civil War — arguably more so than Zemo. Even though his intentions seemed good throughout the movie, the climax of the film showed how cruel and dark Iron Man can really be.
In an attempt to avenge his dead parents, specifically his mother, Tony himself attempted to kill his parents' killer: Bucky Barnes. He dropped his morals and his sense of justice, even when Captain America tried to talk him out of it. It got dark and Tony seemed to not care in the least. In the end, Steve spared Tony's life, but would Tony have done the same for him?
After the fight, when Iron Man is left powerless on the ground, the camera zooms out. Not only do we see the beaten Stark at this point, but we also see his ruined mask.
The mask, having been torn off by Cap, now carries some serious dents and holes. But what I didn't catch the first time around was that these dents and holes make a familiar design — specifically, the facial designs of an Ultron bot.
There is a circle on the side of the Iron Man mask, where the cheek would be, in addition to tints near the eyes. All of the different dents, holes and other markings turn the beloved Iron Mask into the face of Ultron.
This is most likely serving as an analogy. In Age of Ultron, we saw Ultron carrying the same tendencies as Tony Stark. Though Tony never got as far or evil as Ultron did, many of Ultron's actions were inspired by his maker. Now that Stark is the antagonist, however, we finally get to see the darker side of Iron Man, and witness where Ultron got his homicidal tendencies from.
Of course, it may all be a major coincidence, and that Iron Man mask may just happen to have a circle in the same place Ultron did, but I highly doubt it. The Russo brothers love sneaking fun Easter Eggs into their movies, and this appears to be one of them. Well played, boys. I can't wait to find more the third time I see this phenomenal film