How visual effects made Mulan’s battles bigger and its hero fly higher

Disney’s live-action adaptations of its most popular animated features have been huge hits for the studio in recent years. Mulan, the most recent remake, premiered on streaming service Disney+ in September and received high praise from critics for its fresh spin on Chinese folktale The Ballad of Mulan, which inspired Disney’s 1998 animated movie of the same name.

Directed by Niki Caro and starring Yifei Liu in the title role, Mulan follows a teenage girl who disguises herself as a man in order to serve in the army during China’s Han dynasty. The film features an impressive ensemble of martial arts movie veterans, as well as plenty of spectacular choreography and breathtaking sets.

Visual effects supervisor Sean Faden worked with Caro to make the film’s most impressive moments shine a little brighter, and he spoke to Digital Trends about his experience on Mulan and all of the work that goes into making audiences forget there were any visual effects at all.

Digital Trends: Mulan is the kind of film that makes it difficult to know where the in-camera work ends and the visual effects begin. What were some of the biggest elements that occupied your time on the VFX side?

Sean Faden: One of the biggest challenges in this movie from a visual effects standpoint was to create epic scale while at the same time showing the sort of restraint that, in visual effects, we don’t always show. A lot of times we just go for it and add so much detail into the scenes that things can get a little overcooked. But in this case, through the guidance of Niki [Caro] and Mandy [Walker, cinematographer] and our production designer, Grant Major, we had some really great goals and great photography to work from.

That being said, there were some scenes that required visual effects help and CG extensions and CG elements to to make them work. Pretty much any time there were wide shots of a battle and you saw a lot of soldiers or a lot of horses, we were extending those shots. I think they had 67 horses on set at most, and maybe 80 dressed soldiers.

What about environment work? The sets were gorgeous in the film, but I suspect there were some subtle visual effects involved in what we saw.

The locations were amazing. The Ivory Valley in South Island, New Zealand, is one of the most spectacular places you’ll ever see. There are some mountains that surround the valley, but the hero mountain [the active focal point of the scene] that was going to have the avalanche in the film wasn’t actually there. We knew where the ridge [below the mountain] was going to be, but we had to put a mountain on top of that ridge, in the background. The avalanche sequence was a big undertaking, and all of the elements of it — the battlefield, the avalanche, the mountain, and the post-avalanche moment of Mulan galloping through the canyon — were all done by [visual effects studio] Sony Pictures Imageworks. They really did a fantastic job.

Where visual effects really helped out were in replicating and creating digital soldiers to expand the scale of the scene and create digital horses for the shots that had them flowing over the ridgeline toward the camera. The real horses couldn’t ride down that ridge, so we had them at the bottom of the ridge and then built a bunch of CG horses to flow into that group. We used all the horses we had, because visual effects are always going to be better when you have as much real as possible. That was always Niki’s goal: To shoot as much real as possible.

What about the horse that Mulan rides, Black Wind? Was that CG?

During the avalanche, when Mulan is galloping to save Honghui, there are some wide shots when we had Mulan on her horse. Yifei [Liu] is a great horse rider and did a lot of those stunts, but in the scenes where she was galloping in rough snow and reaching out to rescue Honghui, we had her on an awesome mechanical buck [a practical mount made to look like a horse’s back] that was created by our special effects team.

We preprogrammed a galloping cycle and it moved pretty well — she bounced around and did a great job of being convincing on a horse — but Imageworks built this very convincing digital version of Black Wind that held up in even the closest shots. Kudos to them for that achievement, because that’s something I don’t think most people would realize is a digital horse.

Does a project with this level of extensive martial arts choreography create any unique demands on the visual effects side?

Yeah, there are some great scenes where Mulan is running on walls or jumping across rooftops, and in some of the battles, she’s leaping through the air. It’s a challenge for us because, again, we’re trying to make things feel real. You have to balance what’s going to feel magical and special vs. what’s going to feel earthly. You don’t want to defy gravity for too long. You want to believe there’s something special about her that enables her to defy gravity just enough to be a great warrior. So there were a couple of times we ended up cutting her out of a shot and adjusting her trajectory a bit to help.

Most of the wire work was great, but there are always a few moments where it feels a little too horizontal, so that’s when we give her a little more gravity, a little more drop. For example, she lands on a guy’s chest in the corridor near the end of the film, after she jumps off the wall, and they didn’t feel there was enough impact on the landing. So [visual effects studio] Weta added a few extra frames of her sinking her foot and her body into the character’s chest to really sell that impact. Little things like that go a long way.

Is there a scene you’re particularly proud of in the film?

One of my favorite scenes is when we first reveal the desert garrison. There’s a big, wide shot that comes up over the corner of the garrison and reveals this bustling marketplace. It’s one of those shots that went from previs [the earliest, conceptual visualization of the scene] to photography to final composite in such a beautiful, linear way. It looked cool in previs, and it looked amazing when we shot it, but once we put it all together and extended it with visual effects, it was just so beautiful.

It was a pretty big set that they built, and [visual effects studio] Image Engine added people and tents and markets, as well as this very convincing desert environment that wraps around the whole thing. … When I saw that shot, even before it was final, I knew it was going to be one of the great ones in the movie.

What’s the other scene?

The other scene that comes to mind is one of the witch transformation shots. Weta did a couple of transformation shots, but there’s one in particular where a young soldier turns into an alleyway, and as he’s walking, he turns into the witch, and it happens to the rhythm of his footsteps. The witch then becomes a hawk and flies off.

We shot that in China in an alleyway. … We basically shot both actors doing their thing, and Weta did a perfect job of blending everything together. It’s so subtle. It’s a shot you have to watch a couple of times, because the transition from soldier to witch is so elegant and graceful.

That’s everything this movie is when it comes to visual effects: The visual effects support the story and further it, but they don’t knock you on the head and say, “Hey, check out these cool visual effects!” One thing that also worked really well was that the stuntwoman who stood in for Gong Li did this spin right at the end of the scene, and that spin gave Weta a really nice sense of momentum and energy to build off of, and transition into that hawk’s spin. It all worked so well.

Mushu, her dragon sidekick from the animated film, didn’t appear in the live-action Mulan. Assuming there was some discussion about including him early on, was there ever any work done to create him with visual effects?

Mushu was never part of the movie. The phoenix, though, had varying roles as the film developed. Early scripts had the phoenix as more of a sidekick along Mulan’s journey — kind of like Mushu — but it was determined that the phoenix would work better as more of a spiritual guide to Mulan. So the [visual effects] company that was responsible for the phoenix, Framestore, worked with a lot of changes to the character. not just in how it looked, but also how it was going to act. It went from being slightly goofy to being more of a graceful representation of her ancestor.

That kind of thing is tricky to express to a company or to the team. “Okay, now, you guys need to make it spiritual. Don’t make it silly.” But how do you animate that? So there was a challenge in keeping it something that felt like a real bird, but also keeping that fantastic color and quality to it. In the end, we came up with its slow-motion flight pattern and also that particular way the tail feathers flowed behind it. That was how it would move underwater, which was not quite realistic for air, but in the story it helped give it that mystical quality.

Disney’s live-action Mulan is available on Disney+ now.

Editors' Recommendations