Warning: contains spoilers for X-Men: The Trial of Magneto #2!
The future wedding of Tony Stark, aka Iron Man, and major X-Men hero Emma Frost was revealed way back in 2019, and yet as of X-Men: The Trial of Magneto #2, it's looking less likely than ever. While Tony and Emma don't tend to share many adventures, they actually have a history together stretching back to when Emma was a certified villain. However, as the Avengers visit the mutant island of Krakoa to pay their respects following the murder of the Scarlet Witch, Emma seems to hold Tony in less regard than ever, raising some big questions about their supposed nuptials.
Fans learned that Iron Man and the White Queen would tie the knot in History of the Marvel Universe #6 (from Mark Waid, Mike O'Sullivan, and Javier Rodriguez), in which Galactus and Franklin Richards sit at the end of time, reminiscing about major events from the past. While the series' main purpose was to offer fans a single, easily digestible, canon account of Marvel history so far, the final issue sees Franklin mention several moments that haven't yet happened in mainstream canon. In the years since, some - like the King in Black, the Age of Khonshu, and the reign of Emperor Dorrek VII - have come to pass, while others, like "the tragic fate of Luke Cage and Jessica Jones' second child" and "the wedding of Tony Stark and Emma Frost" have yet to occur.
While Marvel is no stranger to alternate futures that never come true, History of the Marvel Universe wasn't presented in that style, and was incredibly sparing in how it presented these coming events, likely so that future writers had room to work if plans changed. But despite that freedom, it remains difficult to see how Emma Frost and Tony Stark could get together. In X-Men: The Trial of Magneto #2 (from Leah Williams and Lucas Werneck), Tony is at his most arrogant and boorish, to the extent that Emma totally blanks him, much to the other Avengers' amusement (she's also pretty frosty to Captain America, still irritated by her recent discovery that she reminds him of his mother.)
But Emma's disdain for Tony isn't the only obstacle to their marriage. Tony is currently seeing Patsy Walker, aka Hellcat, while Emma is a member of the Quiet Council - the ruling body of the new mutant nation of Krakoa - so it might even be politically disadvantageous to her to marry a human. Of course, in comics, words can be twisted to their absolute limits, so it's possible "the wedding of Tony Stark and Emma Frost," has some alternate meaning, but it could also hint that disaster is waiting in Emma's future.
That's because the upcoming Inferno event will see Mystique attempt to destroy Krakoa as a political entity, and marketing materials have suggested Emma may go head-to-head with Professor X and Magneto, having already caused problems with their planned endgame by destroying Mister Sinister's cloning facilities. If Krakoa falls, or Emma is exiled, it's possible a marriage to Tony Stark could become tactically prudent, especially if it offers any displaced mutants some protection - in the alternate future of Wolverine: Old Man Logan, Emma married Doctor Doom to secure safe haven for mutantkind. Emma may dislike Tony as of late, but he's nowhere near as bad as Doom, and Civil War revealed that Iron Man and the White Queen had a "little arrangement" back when she was a wealthy supervillain.
It's possible fans will have a long time to wait until Emma and Tony's wedding, but Jonathan Hickman's epic revamp of the X-Men also occurred in 2019, so it's unlikely Krakoa came out of the blue, and most of the other events mentioned are either concluded or underway. As unlikely as it seems from the most recent interaction between the Avengers and X-Men, there's every reason to suspect Iron Man and Emma Frost will head to the altar sooner rather than later - the real question is what could possibly happen to reignite the White Queen's interest in Tony Stark.
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