While Tony Stark may have clashed with gods and monsters as the Armored Avenger Iron Man, he's still a mortal, and (as the movies have already shown) one day he'll fly into action never to return. However, he won't go down without a fight, and Tony's final mission in Marvel's near future sees him create his most powerful suit - an advanced armor that he expects to be his coffin.
Published in 2001, Marvel Universe: Millennial Visions challenged creators to speculate about possible events characters might go through in the new millennium. The anthology of single-page stories takes some big swings, among them the final suit of an aging Tony Stark, who instigates one last version of his iconic Armor Wars story by attempting to stop a deadly villain distributing armor to thousands of trained killers.
'Iron Man: The Final Days' from Ariel Olivetti and Jorge Lucas sees Tony in his sixties and retired from heroism. The armor that once kept his heart beating is now more essential than ever, to the point that Tony can't take it off. However, when a deadly villain known as Shogun devises a new type of armor that equals Iron Man, Tony must return to his workshop and design one final suit to prevent his legacy turning him into the herald of a new armored age of fascism. Tony's final suit is a huge, bulky suit of armor with a telling skull motif, given that he knows it's unlikely he'll return from this dramatic last mission. In order to take on an army of evil Iron Men, Tony's final suit is identified as "his most powerful Iron Man armor to date." Given that this would include both his Hulkbuster suit and Godbuster armor, Tony's final suit practically elevates him to godhood.
The story is a tragic but fitting finale for Tony Stark, as he ends his life both dependent on his iconic armor and dedicated to his lifelong mission of preventing the weapons proliferation that originally enriched his family. Tony has been through several 'Armor Wars' in which he attempts to prevent armored suits (generally of his own design) falling into the wrong hands, with the famous storyline even inspiring an upcoming Disney+ series of the same name. While the term isn't used in 'The Final Days,' it's clear that Tony's ending is patterned after perhaps his most iconic story as Iron Man. However, there's also an element of the medieval knight - an image Tony has long been obsessed with - charging into battle against impossible odds.
While some stories that imagine Iron Man's end see him retiring with a protégé to carry on his legacy, a tragic but noble final charge is ultimately more fitting. Iron Man is a hero with more demons that most, and it seems like no coincidence that the older Tony is drawn almost indistinguishable from his father - a man whose legacy he both embodied and rejected. Iron Man's final suit is a powerful behemoth intended to surpass everything that came before, but it's also a coffin, and Tony ends his life indistinguishable from the Iron Man persona he created as an expression of his best self. Several ideas from the Millennial Visions line have since made it into Marvel's main continuity, so hopefully some multiversal adventure will bring back this future version of Tony Stark and allow him to showcase what his final and most powerful Iron Man armor is capable of.