3. Teen Tony
If you were like me, you probably saw the first episode of Iron Man: Armored Adventures, and said, Tony Stark as a teenager? To hell with this! and then promptly changed the channel. It might be interesting to read about the adventures of Tony as a teenager for a story or two, but for the most part, hes far more interesting as an adult. One of the things writers loved to do in the 90s was replace classic heroes with young rookies, no matter how much sense it made. Proving that the writers of Iron Man at the time didnt even
remotely understand the character, they decided Tony just wasnt interesting anymore. Did they have another character become Iron Man, such as Rhodey or someone new? Nope! Instead, the Avengers went back in time and brought a nineteen-year-old version of Stark into the future! This new Tony decided to stay in the present, where he enrolled in school, moved into Avengers Mansion, and would constantly use the equipment there (much to the dismay of Jarvis). Not wanting to build a full suit of armor, teen Tony instead used gauntlets and the chest plate and the armor consisted of holograms (because a real suit of armor probably wasnt considered hip enough). The story was mercifully short-lived, as shortly after teen Tonys arrival in the future, he and his other Avengers and the Fantastic Four sacrificed themselves to stop the threat of Onslaught. They all appeared in a pocket universe created by Franklin Richards with new lives and when they returned to the main Marvel Universe, Tony was once again an adult. The official explanation was that when Franklin brought back the Avengers and the Fantastic Four, he brought them back the way he remembered them. So teen Tony became adult Tony, and the whole situation was thankfully never mentioned again.
Likelihood: Robert Downey, Jr.
is Tony Stark, as much as Christopher Reeve was Superman. Replacing him with a teenage version would kill the franchise faster than nipples on the armor.