Spider-Man was key to Iron Man's Avengers: Endgame ending. Stark's relationship with Peter Parker (Tom Holland) played a pivotal part in his arc in the MCU and without it, Tony's Avengers: Endgame's ending simply wouldn't have worked out. With two previous iterations of the web-slinging hero, Marvel Studios inevitably wanted to differentiate their take on their version of the character. Fully taking advantage of the narrative opportunities offered by their interconnected storytelling, they had Tony Stark introduce Spider-Man into the bigger universe he has now taken a more leading role in. After their initial interaction in Captain America: Civil War, the pair developed a mentor-mentee relationship over the course of three more movies until Iron Man's demise in Endgame.

Admittedly, not everyone is thrilled with this dynamic; the most common criticism is Spider-Man being too attached to Iron Man when he's supposed to be an independent hero on his own like how he was in Sony Pictures' previous movies. Both of Peter Parker's solo outing, MCU's inaugural hero was a looming presence: Tony was directly involved in Spider-Man: Homecoming, while his death was a focal point in Spider-Man: Far From Home. It also doesn't help that Uncle Ben, who's supposed to be Peter's primary inspiration has yet to play any part in the character's current arc and there's no indication that Marvel Studios is planning on tackling him anytime soon.

Related: Iron Man Is The Only Original Avenger Without A Marvel Phase 4 Replacement

Peter and Tony's relationship also seemed to be one-sided. As pivotal as Iron Man has been in MCU Spider-Man's arc thus far, the friendly-neighborhood hero doesn't appear to have the same impact on his mentor's story. Looking at how things panned out in Endgame, however, that cannot be farther from the truth.

Spider-Man Showed Tony Stark How To Be A Father (& Forgive His Own)

Avengers Endgame Howard Tony Stark Iron Man

It's no secret that Iron Man's relationship with his father, Howard Stark (John Slattery) was tumultuous. This dysfunctional relationship was rooted in years of Tony Stark feeling uncared for by his own dad who was always busy at work. In Avengers: Endgame, he's able to reconcile with his grievances when Tony had the chance to meet a young Howard months before he was born via the time heist. At this point, Tony was already a father as well, having five-year-old Morgan (Lexi Rabe) with Petter Potts (Gwyneth Paltrow).

It's possible to argue that Tony's primary motivation for forgiving Howard was because of his own experience as one with Morgan, but that's not how simple it is. Prior to Morgan's birth, Tony already got a sense of what it's like to be a father figure when Peter Parker came into his life. Initially reluctant to be Spider-Man's mentor, he realized that since he was the one who brought the friendly-neighborhood hero to the big superhero league, he's responsible for his well-being. That's why he was so disappointed when he learned that the young hero risked his life to pursue Adrian Toomes/Vulture (Michael Keaton) on his own despite his advice. As a consequence, Tony takes back the suit he created for him, explaining that if he's nothing without it, he shouldn't have it in the first place. Somehow, this reminded Tony of his father — muttering to himself how he sounded so much like him. It was obvious that he didn't like this realization considering how he viewed Howard as a parent, but sharing the same perspective eventually helped him slowly understand and even empathize with his father.

Obviously, Endgame upped the ante when Tony got his own biological daughter in Morgan. Unlike his dad, he's involved and hands-on, not wanting to commit the same mistakes done to him growing up knowing how that builds up to resentment. Tony's time with Peter Parker not only prepared him for fatherhood, but it also helped him come to terms with his ill-feelings towards Howard.

Related: How Katherine Langford's Morgan Stark Can Return In The MCU's Future

Spider-Man's Infinity War Death Was Iron Man's Greatest Failure

Spider-Man Infinity War Death Iron Man

Tony Stark made it clear in Spider-Man: Homecoming that if anything happened to Peter Parker, it would be on him. This is the reason why he discouraged the young hero from taking on Vulture and got so mad when he learned that Peter disobeyed direct orders to not be involved. While he finally acknowledged his mentee's capabilities worthy of a spot in the Avengers at the end of the 2017 blockbuster, he remained committed to keeping Spider-Man safe in Avengers: Infinity War. This is why he didn't want him with him aboard the Q-Ship to save Doctor Strange (Benedict Cumberbatch) in the first place, thinking that it would be much safer if he stayed on Earth. However, the web-slinging hero was insistent, refusing to leave his father figure alone.

At the end of Infinity War, Thanos (Josh Brolin) defeated the Avengers — successfully wiping half of life in the universe with the snap of his fingers. The genocide was random, and unfortunately, it also affected some key franchise characters including Spider-Man. It's arguably the most emotional "death" in Infinity War; directors Joe and Anthony Russo milked Peter's dusting knowing how much his relationship with Iron Man resonated with the public. As for Tony, seeing his surrogate son slowly turning to dust in his arms haunted him for a long time; it was his worst nightmare come to life. It didn't help that Peter repeatedly said that he didn't want to go, almost as if he was begging Tony to do something to save him. But Iron Man was helpless; he didn't know what was exactly happening and was unable to do something for his mentee.

Iron Man treated Spider-Man's death in Infinity War as his biggest failure. Even after almost dying himself in space, the very first thing he said when he got back to Earth was that he "lost the kid." Obviously, it didn't matter where Peter was during the decimation, he would still be affected by it, but it didn't matter to Tony. He blamed himself for what happened and he carried that guilt with him for years after.

Iron Man's Endgame Ending Happens Because Of Spider-Man

Tony Stark and Peter Parker Reunion in Endgame

After Thanos' win at the end of Avengers: Infinity War, Tony Stark fully checked out of his superhero gig and focused on his family life instead. In the five-year time-jump, he married Pepper Potts, and together they had Morgan. However, duty called again when the idea for the time heist came up thanks to the emergence of Scott Lang/Ant-Man (Paul Rudd) from the Quantum Realm. Despite Scott, Steve Rogers/Captain America (Chris Evans), and Natasha Romanoff/Black Widow's (Scarlet Johansson) appeal, Tony didn't want to suit back up, perfectly content with what he had. His decision was understandable since it's the only time in his life he had a semblance of a normal family dynamic and he obviously didn't want to lose that, but he ultimately changed his mind after realizing that he finally had a shot at bringing Spider-Man back.

Related: Avengers: Infinity War - Why The Heroes Turn To Dust After Thanos' Snap

The fact that Tony was willing to risk the happy family life he had for a chance to resurrect his surrogate son proves just how important the young hero was to him. He could've stayed put and let the other MCU heroes figure out a way to make time travel possible since there's no personal stake for him in the mission. As Pepper told him, they're fortunate that everyone whos close to them was spared from the snap. But, Tony continued to be haunted by Peter's death, and he knew that he won't be fully at peace knowing that there might be a way to bring back Spider-Man and he didn't do anything about it. So, he ultimately joined the team knowing the risks for himself just so his surrogate son could return.

Spider-Man also played an important part in Iron Man's decision to sacrifice himself to defeat Thanos. As Happy Hogan (Jon Favreau) told the grieving Peter in Spider-Man: Far From Home, he doesn't think that Tony would've wielded the powers all six Infinity Stones knowing it could kill him if the young hero wasn't around to continue his legacy of looking out for the world. Tony's legacy has always been important to him. He was satisfied in knowing that aside from all the technological creations he'd come up with over the years, he's also leaving behind a contemporary who's as committed to the cause as he is.

What Iron Man's Endgame Ending Would Be Like Without Spider-Man

Robert Downey Jr as Tony Stark aka Iron Man in Avengers Endgame

So, would Iron Man's Avengers: Endgame fate have worked if he didn't have the same relationship with Spider-Man?  The answer is yes, but with a big caveat. There were a lot of other factors that built up to his sacrificial play as the movie addressed lingering plot points outside of his bond with Peter Parker. Ultimately, Tony running the sacrificial play worked thematically considering how his journey as a superhero started. While the Russos would've likely found a way to set-up Iron Man's death, however, they would've needed to fundamentally change Avengers: Infinity War as well. Without Spider-Man in the picture, Tony needed to lose something else that's incredibly close to him for his subsequent arc to work. His motivations for being involved in the time heist and wanting to defeat Thanos in Endgame shouldn't be self-serving as it would've cheapened Iron Man's character arc from a self-absorbed industrialist to a selfless hero.

While there are likely other ways to set-up his death without his relationship to Peter Parker, Iron Man's final arc in Avengers: Endgame wouldn't have been quite as thematically intricate and emotionally layered. Spider-Man only came later on in his life, but Peter may have done more for Tony than he did for him. The young hero came into Iron Man's life during one of his lowest points — he was separated from Pepper and was dealing with the Steve Rogers' betrayal, not to mention the collapse of the Avengers, he was mostly alone. Having someone to mentor gave him a purpose. No wonder, Tony was willing to risk it all just to save Peter.

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