It's definitely a trope at this point for Iron Man's armor to fall into the wrong hands; however, in one Marvel Comics story, his Temporal Armor almost led to the Avengers being erased from existence. In Iron Man: Kiss and Kill #1, Iron Man's armor he created alongside Doctor Doom trapped Tony Stark as he was sent back in time. Ultimately, Black Widow was forced to save the day and redirect an explosion at the last second. In the process, she saved Iron Man from being forced to kill his closest allies and himself.
InIron Man: Kiss and Kill #1 by Joe Ahearne, Brian Ching, Michael Atiyeh, and Dave Sharpe, the story centers around the Russians stealing Iron Man's Temporal Armor. Tony Stark teams up with Black Widow to gain more information about his armor's whereabouts and goes undercover as he modifies his appearance to stay disguised. However, the villain Sunset Bain quickly uncovers him, captures Tony, and reveals her plans to use his brainwaves to activate the armor and destroy the Avengers for good. How is that even possible? Through time travel, of course.
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With Iron Man's Temporal Armor is only useable through Tony Stark's brainwaves, Sunset Bain uses Controller technology to take control and turn the hero into a weapon. As Black Widow infiltrates the Russian base, Stark reveals he made the armor alongside Doctor Doom. Natasha Romanoff grabs onto the Iron Man armor as it's shot into the sky; a temporal portal opens up (via Doom's magical upgrade), and Bain's target is revealed: the original Avengers Mansion.
Bain makes Iron Man's Temporal Armor a missile designed to destroy Avengers Mansion to kill the Avengers during their earlier
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