The first armor that the MCU's heroic Tony Stark builds is a matter of life and death. Instead of building a missile for the Ten Rings inside a cave in the middle of the desert.
Mark II - Iron Man
After surviving Afghanistan, Tony Stark returns with an ambitious goal in mind. He commits himself to build an improved version of the armor.
Mark 3 - Iron Man
Tony Stark's Mark 3 armor symbolizes the consolidation of Iron Man as a full-fledged superhero. The most evident change he implements in this model is the iconic red-and-gold scheme.
Mark IV - Iron Man 2
After the Mark III suit is heavily damaged in Tony Stark's final battle with Obadiah Stane, Tony builds the Mark IV armor to replace it.
Mark V - Iron Man 2
Tony Stark made a great first step towards optimized portability several years ahead of his invention of nanotechnology.
Mark VI - Iron Man 2 And The Avengers
When the arc reactor in Tony Stark's chest poisons him, he creates a cleaner and more powerful one plus a proper armor to go with it.
Mark VII - The Avengers
Tony Stark's suit-up after Loki (Tom Hiddleston) threw him off Stark Tower during The Avengershelped the Mark VII armor get engraved in the minds of the fans.
Mark XLII - Iron Man 3
After experimenting with the Iron Legion's 35 Iron Man suits, Tony Stark develops the infamous Mark 42 Iron Man suit.
Mark XLIII - Avengers: Age Of Ultron
Tony Stark promised not to continue his armor-building venture with the "Clean Slate" protocol in Iron Man 3.