The only reason I've ever been able to come up with for this is that they'd already done "evil guy who also has a suit of power armor" in the first Iron Man movie, and they kind of didn't want to retread that.

Iron Man has kind of a big problem in that a lot of his rogues gallery are either 1) shit, 2) not suited to big-budget cinematic fight scenes, or 3) other dudes in power armor.

Like, think about it. If you've already used Iron Monger, who have you got? Well, there's Madame Masque, but it's hard arranging for Tony to fight her in his armor, because he'll just kick the shit out of her, and Madame Masque is a villain you use if you want to highlight Tony's mental and emotional problems. You can't make a movie just about that; the logic of moviemaking dictates that Tony put on his armor and have a knock-down, drag-out fight with someone or something.

There's the Mandarin... who is kinda-sorta a little bit too racist these days (the comics have taken steps to remedy this) and who, again, is difficult for Tony to actually punch. The third movie managed to square that circle nicely, but "the Mandarin" wasn't actually the heavy there.

There's Norman Osborne, who is a Spider-Man villain they lacked the rights to at the time.

There's Justin Hammer, who they did use, but Hammer would have had trouble holding down that movie by himself. "Tony fights an army of drones" is a bit meh.

Who else does Iron Man have who is actually A-list? You can't use any mutants. You can't use Doctor Doom. MODOK is kind of ridiculous. So is the long list of losers like Living Laser and Atom Smasher, although they're at least punchable. If you don't want to repeat yourself with another armor villain, that cuts out Crimson Dynamo and Titanium Man and... well. A lot of other losers.

This isn't to say they couldn't have done a somewhat better job with Ivan Vanko. Mickey Rourke has a lot of screen presence and did a good job with the role; in particular, I very much enjoyed how he conveyed utter contempt for Justin Hammer in very few words, just with body language and attitude. That's hard. But it was somewhat underwritten and badly plotted; if you're going to stitch a bunch of villains together from whole cloth I think you can do it a bit more neatly.

-Merc
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