Secrets of the epic final battle of 'Avengers: Endgame,' from the female Avengers assembling to Thanos's last stand

Warning: This post contains spoilers for the ending of Avengers: Endgame.

The Avengers assemble for the finale battle against Thanos in 'Avengers: Endgame' (Photo: Marvel)
The Avengers assemble for the finale battle against Thanos in 'Avengers: Endgame' (Photo: Marvel)

Avengers: Endgame represents the culmination of the three phases and 21 films comprising the Marvel Cinematic Universe. And Endgame’s final set-piece features almost every super-citizen currently residing in the MCU rallying to Captain America’s side to take on Thanos. It’s a massive sequence that was an even more massive undertaking to bring to life, not only for the cast and filmmakers, but also for the army of visual effects artists from multiple VFX houses that made such Marvel-ous sights as Spider-Man riding on Valkyrie’s winged horse and Iron Man wielding the Infinity Stones possible. Yahoo Entertainment spoke with two of the F/X wizards who had a direct hand in the sequence — Matt Aitken, visual effects supervisor for Weta Digital, and Kevin Martel, animation supervisor for ILM — to learn some of the secrets behind the biggest, baddest battle in Marvel history.

The future is female

Captain Marvel takes on Thanos in the "Women of Marvel" portion of the final battle (Photo: Marvel)
Captain Marvel takes on Thanos in the "Women of Marvel" portion of the final battle (Photo: Marvel)

It may have taken a decade for Marvel Studios to make a female-fronted feature, but Captain Marvel very quickly made up for lost time, earning more than $400 million at the U.S. box office alone. And Carol Danvers (Brie Larson) flexes her muscle against Thanos as well, taking him on solo as well as alongside Marvel’s other mighty women in one of Endgame’s buzziest moments, which brings together every major MCU female hero with one notable exception. (More on her in a moment.) Aitken and his team at Weta took point on providing the pre-visualization for this crucial scene, which has inspired both praise and criticism from all corners of the Internet. “It's a key moment in the battle, and a genuine part of the storytelling,” he says. “And it was there right from the start in all of the versions of the script that I saw.”

At the same time, Aitken reveals that those early versions of the script didn’t necessarily specify what the women would be doing in that scene. In fact, directors Joe and Anthony Russo were still toying with various ideas as late as September 2018, when they reassembled the cast for a block of additional photography. It was during that shoot that all of the actresses featured in the scene — including Larson, Evangeline Lily (Wasp), Gwyneth Paltrow (Pepper Potts/Rescue), Danai Gurira (Okoye), Elizabeth Olsen (Scarlet Witch), Karen Gillan (Nebula), Zoe Saldana (Gamora), Pom Klementieff (Mantis) and Letitia Wright (Shuri) — assembled on set to film their heroic tableau. (For the record, that’s likely the same day that Robert Downey Jr. hosted his “Women of Marvel” lunch, which he later shared widely-circulated pictures of on Instagram.)

“They shot the moment where all the women come together in support of Captain Marvel,” Aitken confirms, adding that the only actresses not present were Tessa Thompson (Valkyrie’s entrance on Pegasus was accomplished via a digital double) and, of course, Scarlett Johansson. As we all know now, Black Widow sacrifices herself midway through the movie so that her fellow Avengers can recover the Soul Stone. But at the time, Aitken was one of the few crew members privy to that piece of information, and he was careful not to share it. “I had seen a couple early cuts of the film, so I knew why Black Widow wasn’t there, but I didn’t want to let on to anyone else at Weta Digital. People kept saying to me, ‘Why is Nat not in that scene?’ I guess they know now!”

That one shot establishes the female heroes’ mission in the scene: clearing a path for Carol so that she can get the gauntlet to the safety of Scott Lang’s van, where the last remaining time machine is housed. But how they were going to do that was still an open question up until February 2019, when Aitken received a call from Marvel asking Weta to take a three-sentence description and turn it into an action-packed scene worthy of cheers and applause. “Over a rather intense three- or four-day period, our fantastic animation team spitballed a bunch of ideas, which we pre-visualized and cut together ourselves,” Aitken says, adding that certain beats were in that initial description, such as the moment where Gamora takes out a gorilla-like alien creature charging at Carol. On the other hand, Valkyrie’s charge at one of the leviathans originated out of Weta’s spitballing sessions.

According to Aitken, the Russos specifically wanted them to find ways for the women collaborate as much as possible. “For example, we've got a team-up between Valkyrie and Scarlet Witch, where Scarlet Witch uses her magic to take one of the Leviathan’s by the throat and steers it away at the same time that Valkyrie is flying down the side of the other Leviathan and splits it open. And when Captain Marvel is racing towards towards the van and Thanos pops up, we have the Wasp, Pepper and Shuri emerge and use their own individual blaster weapons to send him tumbling.”

The latter moment includes a beat that wound up being cut from the final film. “We had this idea that Captain Marvel would zoom up high into the sky as a feint in order to reveal the three women behind her, and then they catch Thanos unaware and blast him. But it didn’t really play clearly, and it was judiciously trimmed out by [Endgame editor] Jeff Ford. The whole scene is very much a collaboration between the filmmakers at Marvel and the animators at Weta Digital. I’ve seen the film twice now with a full audience, and both times the reaction has been incredible to that moment.”

Does whatever an Iron Spider can

Spider-Man and the Avengers charge at Thanos in this unfinished effects shot from 'Avengers: Endgame' (Photo: Marvel)
Spider-Man and the Avengers charge at Thanos in this unfinished effects shot from 'Avengers: Endgame' (Photo: Marvel)

Spider-Man may be the youngest Avenger on the battlefield, but he contributes to the cause through his own ingenuity and the many tricks Tony built into this costume. For example, when Spidey is dog-piled by multiple members of Thanos’s army, he activates his Iron Spider suit’s “Instant Kill” function, and multiple arms shoot out to join the fray. Martel and his ILM animators were in charge of that particular bit of wall-crawler action. “When you’ve got that many characters piling on top of each other, it’s quite an animation challenge to make sure that each character has their own motivation as they’re colliding and climbing over each other. And each of Spidey’s arms is trying its best to keep up with the hoard that’s coming; we had to make sure they were deliberate in their motion.”

ILM also worked on the moment where the newly un-dusted Black Panther defends the gauntlet before it passes to Spider-Man and then to Captain Marvel. “He runs in, takes out some bad guys, does some flips and runs with the gauntlet before he’s taken out.”

Even though both Peter and T’Challa are back in action after a five-year time-out, Martel wanted to make it look as if no time had passed. And, in a sense, time hadn’t passed for them, since they returned to the same places they had previously been dusted unaware that the timeline had moved forward without them. “We thought about what would happen to a character if they’re in incubation for five years, but for them time is different as we all learned. Our approach was that they were ready to go: it’s game time. It’s like Michael Jordan and his ‘Flu Game.’ Even if these guys had any sense of pain or trying to get themselves together, they come out of Dr. Strange’s ports ready to go. We approached the animation as ‘these are the guys we need in the battle.’”

(A quick aside: the final battle scene is jam-packed with Easter eggs, including under-the-radar heroes like Howard the Duck, previously spotted in a Guardians of the Galaxy end-credits scene, and Captain Britain joining the fray.)

It’s getting dusty in here

Thanos gets dusted in 'Avengers: Endgame' (Photo: Marvel)
Thanos gets dusted in 'Avengers: Endgame' (Photo: Marvel)

After turning half of the MCU to dust in Avengers: Infinity War, Thanos gets his own personal Snapture in the climax of Endgame courtesy of Tony Stark. Aitken says that Weta Digital’s animators spent a lot of time thinking about how exactly the purple despot would face his own imminent dusting. In the end, they gave him a thinking man’s death.

“It’s one of the longest shots we’ve ever done on a Marvel movie — he sort of walks and sits down. On the face of it, he’s waiting for it to happen, but there’s a lot of complex emotions playing over his face. We wanted to provide a sense that he’s thinking over everything that’s happened and thinking, ‘Just where did I go wrong? How did I let this happen? If I had done something different, could I have avoided this?’ He knows there’s no point in trying to fight it, so he’s resolute, but there’s also that complexity. Then he drops his head as if to say, ‘I know it’s all over,’ and turns to dust and drifts away.”

Here's how Thanos looked in Weta Digital's computers before the background was added (Photo: Marvel)
Here's how Thanos looked in Weta Digital's computers before the background was added (Photo: Marvel)

Despite being the villain of these two Avengers movies, Thanos gets a hero’s death after a fashion. Aitken notes that for Thanos’s last scene, Weta’s VFX team specifically created a more detailed version of the “blips” (as they called them internally) that turned the good guys to dust in Infinity War. “There’s some extra complexity in what we call the colliders — the visual elements of Thanos that block the wind that’s causing his particles to drift away. As he’s turning to dust, the collider settings were constantly updating to reflect his current state, so we got a lot more detail in terms of how he actually goes.”

Thanos's dusting in an unfinished state (Photo: Marvel)
Thanos's dusting in an unfinished state (Photo: Marvel)

They also made sure to illustrate that while many of the dusted Avengers died in the company of others — think of Peter fading away in Tony’s arms — Thanos floats away alone. “His whole army is gone already; he’s the last to to go because he’s innately able to resist the force of the snap longer than anyone else. We made sure that the frame behind him was even clear of any Avengers. He’s completely by himself, and I think that adds an emotional resonance to that scene as well.”

He was Iron Man

Robert Downey Jr. made his final appearance as Iron Man in 'Avengers: Endgame' (Photo: Walt Disney Studios Motion Pictures / © Marvel Studios / courtesy Everett Collection)
Robert Downey Jr. made his final appearance as Iron Man in 'Avengers: Endgame' (Photo: Walt Disney Studios Motion Pictures / © Marvel Studios / courtesy Everett Collection)

When it comes to emotional resonance, it’s hard to top Robert Downey Jr.’s exit from the MCU. And Aitken wanted to ensure that his team honored Tony’s sacrifice when he allows the otherworldly power of the Infinity Stones to course through his all-too-human body.

“There was a balance in showing the immense power of the stones and the damage they caused him,” he explains, adding that the scene where Iron Man activates the gauntlet was the last visual effects shot to be completed on Endgame.

“There’s a lot of complex simulation that went into that: showing all the destruction without distracting the attention from Robert’s performance. Our first version was too active, and too distracting. In the end, we dialed it back so you get a sense of what’s going on, but it’s not so distracting that you’re not watching Tony’s face through those moments where we really just want you to be with him.”

ILM provided new animation for Tony's Iron Man suit in 'Avengers: Endgame' (Photo: Marvel)
ILM provided new animation for Tony's Iron Man suit in 'Avengers: Endgame' (Photo: Marvel)

Tony’s post-Snap appearance went through multiple design versions as well. “We needed to show the damage that had been wrought on him, and it had to be obvious enough that everyone knew it was going to be fatal — it couldn’t have just been a scratch or a graze. But at the same time, we wanted Tony to keep his dignity through that scene; we didn’t want it to be gory or over the top.”

After working through a series of concept sketches, the team eventually arrived at the version seen in the film, where Tony’s face and neck tissue are badly singed, and the hair on his temples is burnt away. “We blended footage of Robert on the set with a digital double of Tony that has all that damage built into it,” he explains. “In terms of a dramatic conclusion to this phase of the MCU, you couldn’t really go any more dramatic than that.”

Smart Hulk smash

Smart Hulk makes his entrance in 'Avengers: Endgame' (Photo: Marvel)
Smart Hulk makes his entrance in 'Avengers: Endgame' (Photo: Marvel)

Tony isn’t the only Avenger who wields the Infinity Stones in Endgame’s climax, of course: the gamma-powered Hulk uses them to bring the heroes back in the first place. And while they don’t kill him, the stones definitely leave a mark. “We kept telling ourselves, ‘This is the most pain he’s ever been in,’” says Martel, whose ILM team designed Endgame’s new, improved version of the MCU’s green giant (played by Mark Ruffalo) — now with Bruce Banner’s brains to go along with Hulk’s brawn. “A lot of the discuss was about how many veins are going to pop out on his forehead, and how much stress was going to be on his face. We wanted to push it to the max, and kept reevaluating where we could add some extra anguish.”

The physical toll of his brush with the gauntlet is memorialized in Hulk’s post-Snap arm. “His arm gets sizzled and fried — you can see later in the film how shriveled and burnt it is. Those scenes were very carefully considered and combed over to make sure that we pushed it as far as we could.”

ILM's unfinished version of Smart Hulk in 'Avengers: Endgame' (Photo: Marvel)
ILM's unfinished version of Smart Hulk in 'Avengers: Endgame' (Photo: Marvel)

Speaking with Yahoo Entertainment, Endgame writers Christopher Markus and Stephen McFeely revealed that “Smart Hulk” (better known in the comics as “Professor Hulk”) originally made his appearance at the end of Infinity War. Martel confirms that account, but says that plans changed before that scene would have reached ILM animators. In fact, they were never called upon to animate Banner’s permanent transformation into Smart Hulk — a scene that the the Russos deliberately left out. “They wanted to do a straight introduction of Smart Hulk; to see him in that form right away adds an extra level of comedy to it. Also, watching Ant-Man’s confused reaction to him — it’s like we’re there with him, which is a fun way to do the reveal. We kept improving the character pretty deep into the production of Endgame. ... It was really about trying to figure out how much Mark and how much creature. You don't want to get into a place where the end result looks like a Photoshop version of Mark’s head turned green, yet you still want to make sure that all of Mark's performance is coming through. Once we landed on that spot where we could see Mark acting through the character, then we were off to the races.”

The final version of Smart Hulk's ride to New Asgard (Photo: Marvel)
The final version of Smart Hulk's ride to New Asgard (Photo: Marvel)

One of Martel’s favorite character details are sitting front and center on Smart Hulk’s face — those smart-looking, black-rimmed spectacles. “The glasses placement in each scene was carefully considered to give maximum appeal and what would work best with his expression. We wanted to make sure that if he did a squint or a scrunch, the glasses would follow that extra movement. They’re also just a wonderful prop to have: like when Hulk goes to take a selfie with those kids in the diner, he takes his glasses off. The thought its: ‘I look a little more handsome with the glasses off.’ All those little details keep things feeling very natural and part of the scene.”

Avengers: Endgame is playing in theaters now.

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