Phantom Blade Zero’s Years-Long Mocap Process Is All About Honoring Kung Fu Tradition
Excruciating detail.
Last month, I flew halfway around the world to get an inside look at the development of Phantom Blade Zero. What resulted was five days of the best food I’ve ever eaten, a last-minute trip to the Great Wall with a taxi driver playing Mario Kart through mountain passes, and a fascinatingly deep look at Phantom Blade’s most important aspect, mocap.
Phantom Blade harnesses the gorgeously fluid action of Wuxia, a genre of Chinese fiction that focuses on the adventures of larger-than-life martial artists. To that end, nearly every weapon, enemy, and move in the games is fully motion captured to make the game feel as authentic as possible. It’s a massive undertaking, but a kung fu expert named Master Yang has been working on Phantom Blade’s mocap since 2023, as the game’s lead combat action director.
If you’re unfamiliar with mocap, it’s a complex process of capturing movements of objects of people, and then translating that onto the game’s 3D models. You’ve likely seen videos or images of mocap suits covered with dots, in rooms full of cameras. Mocap is complex enough on its own, but the complexity only goes up even more when you’re capturing master martial artists pulling off flying spins and fantastical Wuxia action.
Yang’s team goes through multiple iterations of each capture to make sure they get the right one.
After going hands-on with Phantom Blade, the game’s fluid animation is one of its strongest aspects, tying together with the sheer variety of weapons, combos, and combat options. Within minutes of meeting Yang, it quickly became apparent that he’s one of the most charismatic individuals I’ve ever met — bursting at the seams to gleefully talk about his work, the history of kung fu, and the challenge of infusing Wuxia style into a video game. But it’s also clear that Yang isn’t just aware of the challenge, but relishes in it.
“The way I see it is that good game design needs originalty, and anything truly original always comes with some level of risk,” Yang says, “Assessing that risk is essential, because you don’t want to create something so different that no one understands it, or push the players’ boundaries to the point where they can no longer relate to the experience. As long as creative risks remain in a relatively safe range, I think it’s worth it.”
But perhaps what’s most interesting about Yang’s ambitious approach is how he tries to separate capturing action from actually playing the game itself. Yang wants his contribution, the action, to feel as pure as humanly possible. And to that end, while the game’s director Soulframe, does offer input, he trusts Yang and his team to figure things out on their own and find the right direction. It’s a constant feedback loop between the mocap, animation, and core development teams.
Master Yang explains the mocap process of a boss.
“Personally I’m not really an expert at it [the game] — and honestly, I don’t want to be. Because once you become an expert, you start getting boxed in,” Yang says, “If you’re very skilled at a game, you naturally get used to a certain playstyle, a way of fighting, or a certain kind of game design. Without even noticing, those habits will influence you.”
After two days of sitting in a chair playing Phantom Blade, Yang put us through the wringer with his approach. Our group of journalists and influencers was put through a training session of a “basic,” kung fu form. Over an hour, we learned the five steps of this form, and admittedly, most of us, including myself, looked like babies learning to walk for the first time.
This exhausting hour was just the start of our day, as we’d then get a feel for how Yang and his team use a pulley system to orchestrate the game’s high-flying action, followed by a full mocap session of a fight scene. This multi-step process took nearly the entire day, and it wouldn’t have even been all the work needed for a single weapon in Phantom Blade.
But in between all of that, I was able to glean a lot about how Yang’s creative process works, and how that’s being injected into Phantom Blade.
Yang cites films like Crouching Tiger, Hidden Dragon as a direct influence, and while I mentioned earlier that Phantom Blade is inspired by Wuxia, there’s an important distinction to make.
“Everyone already has their own idea of what Wuxia means, so the first step is to break away from that fixed definition. Wuxia is different from another Chinese genre called Xianxia — the key difference lies in the boundaries: how far can a hero go, how high can they leap?” Yang notes, “Even when the characters seem extraordinary, they must still stay within the limits of human ability.”
Master Yang shows off a traditional Chinese Lion dance, which is used for one of the bosses, as seen in Phantom Blade’s first trailer.
That brings up another interesting point, however, as all of the mocap is done at the exact speed you’ll see it in-game. Yang doesn’t want to speed up the animation in post-production, as he feels that it risks making it look “fake.” So to that end, every mocap session is done with the intensity that it needs to be reperformed in the game; every blow has to have force behind it. That’s exactly why keeping the action grounded is so important, even when you’re fighting monstrous bosses or wraiths that can fly through the air.
To accomplish this, actors are put into a variety of different harnesses or braces that are then attached to a pulley system, at multiple points to distribute the weight efficiently. Multiple team members then have to work the pulley system in tandem with the martial artists executing moves. And as you’d expect, sometimes capturing even the smallest piece of a weapon’s movement requires multiple takes. Again, where we journalists and influencers bumbled our way through air maneuvers, the experts made it look like a snap. I was especially wary of trying to do flips on the pulley system, considering the massive “kung fu master” lunch we’d had just hours before.
But as much of a bumbling fool as I’m sure I looked like, there are, inherently, some shortcomings of the technology that make capturing Yang’s full ambitions difficult. In particular, optical-based motion capture is hard to do when the subjects being captured are obscured by objects, or other people. That means moves that have a lot of rolling, or battles with a lot of characters, can be difficult. Yang references the Seven Stars fight seen in the game’s demo and Year of the Snake trailer, where the protagonist Soul fights seven different enemies at once. In this instance, the team captured as much as humanly possible, then filled in the missing parts with manual animation.
The mocap process uses a pulley system with multiple points of contact on each actor for added safety. But Yang notes there’s still always a chance of injury, especially with the actions the team are pulling off.
My single day of visiting a mocap studio was so exhausting that it’s made me have an entirely newfound respect for the art of performance capture. The amount of work that’s gone into this game is already mind-boggling, with dozens of different weapons, the array of enemies I fought in the demo, and everything else.
After days of being in Beijing and Shanghai, it was fascinating to hear Yang talk about his work with such vim and passion — but in a decidedly different way from the rest of the development team. It feels like, to Yang, Phantom Blade is an opportunity to share China’s rich culture and the martial arts that he’s dedicated his life to, with the rest of the world. And at least in video games, that’s an opportunity that hasn’t existed until right now.
Yang’s team aims to mocap nearly every action in the game, giving a sense of authenticity to the gam’es kung fu action.
To Yang, the most important thing is that all of the game’s moves are rooted in Chinese kung fu. The team doesn’t need to stay within an ethereal boundary of what makes something “wuxia,” but they won’t introduce any elements from other martial arts like jujitsu. There’s an excruciating amount of effort to stay true to the roots of Chinese martial arts, and using those roots to help accentuate Phantom Blade’s style, characters, and tone. And while the core development team might take a different approach to cultural authenticity, that’s at the heart of everything for Yang.
“Crouching Tiger, Hidden Dragon reflects the emotional character of that generation of Chinese people being reserved, humble, composed, and strong,” Yang says, “The appreciation of modesty, the tendency to seek inward, the diversity of weapons (tools) for specific purposes. Who you are defines how you fight. All these factors combined make up the essence of Chinese culture. A quiet strength expressed through great humility and restraint.”
