The ability of Kang the Conqueror to alter timelines is rarely displayed in the comics, but on one occasion his meddling in Iron Man's past created a string of tragedies and convoluted events that led to a Tony Stark resurrection that fans of his version in the MCU would absolutely loathe.
In the Marvel Cinematic Universe, Robert Downey Junior's portrayal of Tony Stark was so iconic that fans would never accept him being replaced by another actor. This creates an issue for most of the first-generation MCU characters, including Iron Man and Captain America, who have to be killed or removed forever once their actors move on to other things. Comic books, however, allow for more freedom, but this does not always lead to successful ideas. When Kang the Conqueror corrupted Tony Stark as part of his plan to destroy the Avengers, a younger version of Iron Man took his place, only to be later erased when things had to go back to the status quo. The time-traveling Kang the Conqueror is one of the Avengers' classic foes. His ability to move freely through time and change the course of history would make Kang the deadliest villain, but his strong sense of honor usually acts as a restrain.
Related: Kang the Conqueror is the Secret Origin of Marvel's Very First Hero
The events of Avengers: The Crossing (the work of a large creative team comprising Terry Kavanagh, Bob Harras, Dan Abnett, Andy Lanning, Ben Raab, and Mike Deodato Jr), showed just how dangerous Kang can be when he decides to mess with the timelines. Kang traveled back in time and corrupted a young Tony Stark, turning him into a villain. When the Avengers found out, they recruited a «pure», teen Tony from the past, to fight their former comrade. When the older Tony was
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