'Iron Man 3' VFX artists on the Mark 42 suit design

Tony Stark is invincible — at least when it comes to the numbers for Iron Man 3, that is. A whopping $174 million at the box office opening weekend. A staggering $409 million domestically. More than $1.2 billion grossed worldwide.

But the genius/billionaire/playboy/philanthropist character who’s appeared in five Marvel films so far was fallible in his third standalone feature, spending much of his post-Avengers time in his basement, designing prototype after prototype of his Iron Man suits to keep his mind off his near-death experience.

The most eye-popping one he built: The Mark 42 (below), which he can summon remotely in individual pieces to his body via sensors he injected under his skin.

Of course, “Tony Stark” didn’t build the suit at all; instead, 1500 visual effects artists worked on the film, and according to Chris Townsend, the film’s visual effects supervisor, at least half of them worked on the Mark 42.

“We ended up having eight [visual effects] companies throughout the world working on that particular suit,” he tells EW. “Hopefully in the end, for the audience, if we’ve done our jobs right, they’ll think from shot to shot, it looks like it’s all created by Tony Stark.”

EW talked to the minds who spearheaded the suit’s concept — the real Tony Starks, if you will — to get a breakdown of the process, from the initial idea to adding Robert Downey Jr.

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THE IDEA

Considering the film’s goal of portraying a weakened Tony Stark, director Shane Black wanted a suit that would physically mirror the hero’s plight while also elevating it beyond previous incarnations. When Ryan Meinerding, Marvel’s head of visual development, introduced the idea of a suit breaking down into component parts — an update on the comic’s Extremis story line that saw Tony fuse with his suit — Black jumped on board.

“[Shane] wanted to do something to push the envelope further and further,” saysthe film’s visual effects supervisor Chris Townsend. “We saw the last time, in The Avengers, the suit flying down and landing on him, so we wanted to make it a little more elegant than that.”

Challenges immediately appeared. The suit had to retain its iconic silhouette, but needed to look more mechanical and fresh, a tough balance to strike.

Not only that, but the suit would require more work with designing the individual parts, given how they had to separate on screen in multiple sequences.

“We needed every single aspect to be carried off well,” Townsend says of the suit connecting idea. “I thought it was a very exciting sequence conceptually.”

THE SUIT’S “LOOK”

Once Townsend had a rough mockup ready, he sent it to Meinerding, whose visual development team began creating versions of the Mark 42, focusing on its overall look.

“Our department is just the kernel where stuff begins,” Meinerding says. “[The suits] are fairly complicated things to design, and they’re time intensive.”

Just how time intensive? Several months worth, he says, of refining the suit’s details after Black chose the winning design — a primarily gold suit Meinerding presented at the first meeting with Black and producer Kevin Feige — from among nearly 50 designs his team created. (Many of the unique designs ended up in the climactic sequence with Stark’s army of suits.)

The team then continued to tweak the colors while an in-house modeler built a 3D digital version of the suit for Meinerding’s team to work with and test for lighting. Meinerding says his team was worried most about the champagne color of the suit, which diverged from the previous scarlet-based ones.

THE PARTS

To figure out the animation of the individual pieces, Munich-based visual effects company Trixter took the reins in April 2012 on more than 200 shots that featured the Mark 42 connecting and breaking apart. But because they had to debut a first look at the suit by the start of Comic-Con, the company had less than eight weeks to produce an initial concept.

“We had to split the design and we split the suit,” Trixter visual effects supervisor Alessandro Cioffi says. “It was madness, but it was also very exciting. After Comic-Con, we were exhausted, literally, because it was like a time race.”

Cioffi and his team worked in conjunction with Townsend to do two things: Make the technology of the suit make sense visually, and create a way to make the individual pieces — the shoulders, the boots, the gloves, etc. — look unique. The latter mattered especially in the first sequence the company animated, in which Stark tests the Mark 42 while the suit rests in pieces around him in his basement.

“We didn’t want them to look like friendly little robots,” Townsend says, adding that the parts couldn’t resemble anything the audience would recognize, such as household objects. “You wanted to give them some attitude because Tony’s got some attitude towards the pieces.”

For example, when Cioffi sent Townsend a possible boot design, Townsend immediately drew a flower inside it, saying the design looked too much like a flower pot.

“I’m looking at thousands of shots every day, and I’m trying to put it all together, so when I see something, I think immediately, ‘Wow, that looks like a flower pot,’ so that’s my instinct,” Townsend explains. “I have to trust my instincts. If something looks like a flower pot, then you call it as a flower pot.”

But Cioffi didn’t mind the rapid-fire comments. “It was a little bit of a back and forth, a beautiful collaboration,” he says. “It was like an orchestra.”

Once the pieces were fully designed, Trixter needed to tackle the interior mechanics, concentrating on the pieces’ movements (above). Cioffi says the animation had to be “mechanically coherent,” and the team digitally observed every possible angle.

Legacy FX, a visual effects house based in Los Angeles, built the actual props afterward, sending back notes about the plausibility of each design. Trixter took the changes into account and had to turn some pieces “upside down like a glove,” Cioffi says, and even started some parts from scratch.

From there, the final pieces would be animated into the suit’s sequences, with Townsend making sure the animation language stayed consistent throughout the film.

THE ACTOR

The scenes wouldn’t be complete without Robert Downey Jr., who had to choreograph his moves for the suit without, obviously, having the actual pieces fly onto him. It wasn’t the easiest task.

“For an actor it was particularly challenging, because he had to simulate how these pieces were connecting onto his body in a pretty violent way,” Cioffi says. “Afterwards, we had to follow his body movements and connect the parts and animate the parts accordingly.”

In fact, the first scene Townsend remembers shooting with Downey Jr. was the first suit connecting sequence in the basement. And without the physical props, the team had to figure out a way to help him create the “violent” reactionary movements.

“I was not sure we were going to be able to do it, whether we were going to have to put wires on Robert and yank him to get that sort of staccato feeling,” he says. “But he was brilliant at being able to sort of mime it and be just a performer.”

Downey Jr. though, did struggle at first with the jerky movements — “He sort of moved at times like a dancer,” Townsend recalls — so the visual effects team produced a special suit to help him concentrate and restrict his movements.

Still, Townsend remembers the actor had fun, pulling his signature schtick with his miming job. In that first sequence, the actor dubbed the final pieces — the plate that attaches over his behind — the “Ass-guard,” a play on the name “Asgard,” a.k.a. Thor’s extraterrestrial home.

THE MARK 43?

So after the colossal effort of literally putting the Mark 42 together, where can “Tony Stark” possibly go next with his suits?

Cioffi’s not telling, and says he’s just happy with how this one turned out, especially with the workflow. “For me personally, as a visual effects supervisor, this was like dream land,” he says. “We got full control and confidence in what we were doing, because we knew it in and out. We could follow the entire process, it was fantastic.”

But Meinerding, for his part, admits the next incarnation of the suit will be tough to pull off.

“When we did the 42, I think we collectively look back at it and say, ‘Well, I don’t really know what we do after this,'” he says. “It felt fresh and it felt interesting, so we have a bit of a challenge in front of us… We’ll leave it up to Joss [Whedon] to see what he comes up with.”