Iron Man Suits
To unlock the different Iron Man suits you must beat the game or beat the different levels of One Man Army
Classic Suit: Beat One Man Army vs. Mercs
Extremis Suit: Beat One Man Army vs. Maggia
Hulkbuster: Beat One Man Army vs. AIM-X
Mark l Suit: Beat One Man Army vs. AIM
Mark ll Suit: Beat One Man Army vs. Ten Rings
Ultimate Suit: Beat story mode
cool thx