The shrapnel floating through his bloodstream came from a bomb that hit him in the opening scenes of Iron Man. To combat these fragments of metal from killing him, he created a collider to place within his chest and keep himself alive.
After battling against Whiplash (Mickey Rourke) in Iron Man 2, Tony eventually made a new element to keep himself alive.
This infinitely-powerful element became the chest piece of all of Tony’s Iron Man suits in the films that followed and originally came from plans written by his father, Howard Stark (John Slattery).
However, the plans from this element first came from Howard studying the Tesseract.
During the events of Avengers Infinity War Thanos crushed the Tesseract and revealed it was housing the Space Stone.
This means the plans Tony deciphered from his father’s work originally came from an Infinity Stone.
Therefore, the element and power supply he housed in his chest in every Iron Man suit was actually a synthetically created Infinity Stone.
By wielding a stone and using its power for years, Tony would have been able to do some incredible things, including taking on the power of the stones in the first place.
2019 film Spider-Man: Far From Home included a scene that showcased Tony’s technology and information being passed on to Peter following his death.
Considering Peter has one of the sharpest minds in the Marvel Cinematic Universe, he may be able to utilise this synthetic stone information for his own suits in future films, just like his mentor did.
Tony’s death left quite the gap in the Avengers line-up, but in a recent interview Captain America star Chris Evans responded to the notion of Downey Jr being replaced as the hero in future movies.
He said: “I don’t think there is anything anyone on this planet can do that would somehow improve upon what Downey has done.”
Evans continued: “I don’t consider that a role that’s gonna be like a James Bond or a Superman or Batman, that somehow other people get a bite at the apple. [Downey Jr] is Iron Man, the end.”
The 39-year-old actor went on to joke he would consider becoming Iron Man, however, adding: “The paycheques would be nice.
“The role is so fun, the role is… you know, he’s the engine he’s the life. But I suppose that’s kind of signing up for failure.”
The Avengers films are available on Disney Plus now.