MOBILE SUIT GUNDAM GQuuuuuuX MECHANICAL DESIGN
IKUTO YAMASHITA INTERVIEW

With its theatrical premiere followed swiftly by a TV series, Mobile Suit Gundam GQuuuuuuX has taken the 2025 anime scene by storm. While the compelling narrative is undoubtedly a draw, the mechanical designs have generated significant buzz, from reimagined classics like the Zaku and the “White Gundam” to the titular machine, GQuuuuuuX. We sat down with Ikuto Yamashita, the man behind these groundbreaking designs, renowned for his philosophy of expressing more than just performance through shape. (Interview by Takaaki Kuwaki)

■ DESIGNING GUNDAM: THE GQuuuuuux

――The GQuuuuuuX and the Red (White) Gundam are both lead machines but feel like they’re from entirely different series due to their distinct approaches.

Yamashita: I really hoped to achieve precisely that feeling, that these mobile suits would feel refreshingly different. I belong to the original Gundam generation, but truthfully, I didn’t closely follow each installment as it aired. My introduction to Mobile Suit Gundam was actually through reruns. When it originally aired, I was completely absorbed by Future Boy Conan instead! (laughs) But revisiting the designs to create my own, I’m continually amazed at how incredible every Gundam has been through the years.

――This year marks Gundam’s 45th anniversary, with numerous unique takes on the iconic mecha across various adaptations.

Yamashita: Designers like Kanetake Ebikawa have set such a high bar with sleek, futuristic, and undeniably cool Gundams that it initially felt like there was nowhere new to go. However, Akiman (Akira Yasuda) really shattered preconceived notions of Gundam aesthetics with G-Reco.

――Did Sunrise (Bandai Namco Filmworks) give you specific directions or requests?

Yamashita: They never told me, “Make this kind of Gundam,” nor did they caution me against breaking from tradition.

――With that creative freedom, did the process become more enjoyable or more difficult?

Yamashita: Yes, well, given how extraordinary past Gundam designs have been, I constantly found myself wondering, “Why am I drawing so many intricate lines? Isn’t there a simpler way?” (laughs)

――What was the most challenging part of designing these Gundams?

Yamashita: The head design proved particularly tough. The GQuuuuuuX’s horn is essentially a last-ditch effort to retain Gundam-like features. Producer Yuki Sugitani humorously insisted, “It needs teeth!” (laughs) But the horn required a reason beyond tradition. When we settled on the idea of it being an Omega Psycommu locking device, everything finally clicked, and GQuuuuuuX felt authentically “Gundam.”

――Speaking of “teeth,” they’re explicitly mentioned in the show. Did you have any particular attachment to that feature?

Yamashita: They’re glowing faintly in the teaser visual too, right? That was Director Kazuya Tsurumaki’s idea to “just show them from the start!”

――The coloring is classic Gundam tricolor.

Yamashita: Actually, director Tsurumaki initially suggested it didn’t have to be tricolor since it was an experimental machine, it could’ve been gray. But since the Red Gundam was solid red, the tricolor spot was open. Plus, I joked, “If it’s tricolor, people will instantly recognize it as Gundam no matter how unconventional it is!” (laughs)

■ THE “LOOSE ENDS” OF GQuuuuuuX

――Could you talk more about the design specifics of GQuuuuuuX?

Yamashita: I intended to mention this after the show finished airing: despite all my ambitious ideas, there are several unfinished elements, what I call “loose ends.” As designs become character-like, they often cease to function realistically as machines.

――Could you give a specific example?

Yamashita: The thigh component with pipes on top actually connects nowhere.

――Interesting! Why was that?

Yamashita: Initially, additional thrusters were planned there. It was part of our idea exploration phase. Similar unfinished spots are all over the machine. For instance, beam sabers mount on the rear waist, yet there are unused hardpoints on the sides.

――These loose ends sound more like “potential growth points.”

Yamashita: You can see multiple tanks that look like rocket engines, but then the question comes up: “So what’s the fuel for rocket engines in the Gundam world, in the Universal Century?” For the Zaku, I considered thermonuclear propulsion with simple water as fuel. But for the GQuuuuuuX, separating propellant and oxidizer seemed smarter, so the dangerous fuels ended up isolated in the thigh’s red tanks.

――Positioned on the inner thighs to be harder to hit. Should we consider those round parts around the Zaku’s thighs to be those fuel tanks?

Yamashita: For the Zaku, as I mentioned earlier, I was thinking it uses thermonuclear propulsion with thermal expansion, so the contents are just water. That’s why the tanks have an exposed structure.

――A clear evolution from One Year War mobile suits to modern designs.

Yamashita: But even that setting is vague, and the actual details are unclear… that’s how the story goes.

――What about the collar-like structure around the neck?

Yamashita: It has a scarf-like structure, but initially it was intended as a system for constantly monitoring the Omega Psycommu system in the head. My initial concept had it spinning periodically, something easily achievable with modern CGI, or so I thought. But apparently that’s actually quite difficult (laughs).

――Was there some technical hurdle?

Yamashita: Film moves at a constant speed, but animation itself doesn’t progress at a constant rate, right? Whether it’s mecha or characters, they move, stop, sometimes go into slow motion, and so on. So when you insert something rotating at a constant speed into that, it becomes quite complicated. The risk of continuity errors was too high, so we had to scrap the idea.

――According to the setting material, they’re neck vulcans, right? The blue parts open to reveal them.

Yamashita: The structure does allow for rotation (of the collar area), but originally these were parts meant for a different purpose. This is another one of those misplaced “loose ends.”

――It’s an unusual placement compared to other Gundams.

Yamashita: After explicitly showing that head-mounted vulcans wouldn’t fit on the Red Gundam, we inadvertently created a standard where no mobile suit in the show could have head-mounted vulcans. Ironically, I cornered myself! (laughs) The production staff even had to ask, “Those holes on the Gelgoog’s head aren’t machine guns, are they?”

――If we’re talking about the GM from Mobile Suit Gundam, which was the design motif for the Gelgoog, it would have vulcan cannons just like the Gundam.

Yamashita: In the Gelgoog’s case, they’re sensors. If we wanted vulcans on the Gelgoog, we’d have to design something new, protruding parts, just like we did with the Red Gundam.

■ THE WHITE AND RED GUNDAMS

――Could you talk about your approach to designing the Red (and White) Gundam?

Yamashita: I went back to my initial impressions of the original Gundam. When I first saw it, my immediate reaction was, “Is this really the main robot?” I wanted to recapture that peculiar feeling in my design.

――At the time, what specifically made the original Gundam feel so different from traditional hero robots?

Yamashita: Before Gundam, robots had obvious, fixed weaponry. Also, there weren’t any predominantly white robots. Typically, colors got darker toward the extremities, likely because darker colors conveyed strength.

――But the Gundam featured white prominently on its arms and legs. Earlier Sunrise series like Invincible Steel Man Daitarn 3 or Invincible Super Man Zambot 3 had clearer, more colorful weapons.

Yamashita: Exactly, which is why the Gundam stood out as so unconventional. These days, Gundam designs keep evolving and being updated by various artists. But I wanted modern audiences to experience that original feeling of strangeness we felt back then.

――The White Gundam notably features more yellow compared to previous designs. Is that indicative of its experimental nature?

Yamashita: Gunpla builders typically favor white and blue, avoiding yellow, right? Personally, I like oranges and yellows (laughs). They give off a heavy-machinery vibe. Also, though it differs from the final design, in the early designs I was trying to support the shoulders with a double wishbone structure.

――Like a bird’s wishbone or a car’s suspension?

Yamashita: I was even planning to add moving parts to the chest and eliminate the traditional front-grille-like chest vents. However, midway, the idea emerged that Gundam needs chest exhaust vents simply because “it’s a Gundam, it has to vent something!” (laughs).

――So it became a necessary visual element?

Yamashita: Although, if you think about it logically, a space-use mobile suit venting air seems pointless, but visually removing them entirely would be problematic. So, I intended to subtly substitute or obscure them.

――How much freedom did you feel you had with these designs?

Yamashita: Initially, I thought I could do pretty much whatever I wanted, but the director also had specific visions, so there were boundaries I couldn’t cross.

――By the way, which did you design first, the red or white Gundam?

Yamashita: I believe I drew them together. The concept was clear from the start. Director Tsurumaki visited the life-sized Gundam and remarked how surprisingly small its head appeared. The maintenance platforms around it had reduced-scale railings to make the head seem bigger.

――You mean the moving Gundam at Gundam Factory Yokohama?

Yamashita: Most likely. That inspired the idea that a sizable Vulcan cannon wouldn’t realistically fit inside the head, prompting us to make it external. Although in-universe, Vulcans are portrayed as weak weapons, a 20–30 mm cannon mounted on a rotating head would be extremely powerful in reality.

――Compared to beam rifles that can destroy a mobile suit in one shot, they do seem less powerful by comparison.

Yamashita: Beam rifles would realistically demand cautious use. Vulcans firing physical ammunition are incredibly versatile, able to change direction and align with the main sensors. They’re like real-world CIWS anti-aircraft systems on ships or the spherical sensor mounts you see on helicopters. I wanted to bring that realism to the Gundam’s head.

――The camera lenses in the Gundam’s eyes are also distinctive.

Yamashita: I’d grown tired of filling the eyes with multiple lenses, so I considered using densely packed hexagonal reflective mirrors. Although, visualizing such intricate internal details clearly in animation could be challenging. (laughs)

■ COCKPIT OF AN 18m MOBILE SUIT

――Could you tell us about your cockpit design?

Yamashita: Both the Red Gundam and GQuuuuuuX have cockpits with expansive downward views, unobstructed by consoles. The closest real-world equivalent would be the giant giraffe cranes used at harbors.

――Those massive port gantry cranes?

Yamashita: Sitting inside one is terrifying because your view straight down is completely clear. (laughs) But logically, a giant walking mobile suit would definitely need excellent downward visibility.

――Especially considering that mobile suit combat is visually oriented.

Yamashita: True, but it’s not ideal for TV animation because it’s incredibly labor-intensive. Imagine animating cockpit views with changing angles, it’d be an animator’s nightmare! (laughs)

――That’s a setting that would make animators cry! (laughs)

Yamashita: Before working on Gundam, I always wished to see more scenes showing humans directly interacting with robots. Gundam typically avoids this due to production complexity as pilots inside the cockpits usually aren’t shown alongside external robot shots, and scenes outside typically just focus on the mobile suit’s feet. Drawing people and machines interacting is just really tough!

――You got a taste of TV animation realities.

Yamashita: If you were to depict those interactions realistically, you’d need artists who can draw both characters and mecha simultaneously, and that’s rare. Sunrise (now Bandai Namco Filmworks) devised this practical, streamlined approach to ensure weekly production was manageable.

――Yet, this series achieved precisely that integration within a TV production.

Yamashita: It was always a dream of mine. With the Red Gundam, we proposed having the cockpit visibly protrude forward with the pilot inside. Actually, Victory Gundam was the first to achieve something similar.

――In Mobile Suit Victory Gundam, the mobile suits were downsized to about 15 meters specifically to better illustrate human-to-machine scale.

Yamashita: Right, it’s genuinely difficult work, typically omitted from standard TV anime. Usually, artists would just refuse outright, saying, “Please don’t make us draw this!” (laughs)

■ OTHER MOBILE SUITS

――Could you share your thoughts on designing the Zaku?

Yamashita: I wanted it to feel both like an ordinary soldier and something special-ops inspired, a machine capturing the essential coolness of a versatile, general-purpose unit. I think that’s probably what Director Tsurumaki had in mind as well.

――In other words, stripping away overt “character” elements?

Yamashita: Exactly. The Zaku has a single eye, which inherently removes character-like personality. As soon as a robot has two eyes, it feels like it has a soul. Kunio Okawara, who originally designed that mono-eyed robot, was truly brilliant.

――The G-Armor and Mobile Light Armor designs published in the theatrical premiere’s Design Works Vol. 2 were exceptionally cool. Fans would love to see them as Gunpla kits.

Yamashita: Those designs are so bulky and elaborate, they’d never realistically fit into their carriers! (laughs) Since G-Armor is impossible, I drew it thinking we’d have to suspend it from both sides.

――There’s high anticipation for potential MSV expansions, especially your takes on the Octo Zaku (aka Psycommu High Mobility Test Zaku) or the Zaku Flipper.

Yamashita: Honestly, I’m not that familiar with the detailed MSV line, I mostly know the TV series. However, philosophically, the legless Octo Zaku and my ideas are similar. Since these units frequently return damaged, losing the legs from the knee down felt perfectly logical.

――Io Takuya handled the detailed designs for the Rick Dom and Gelgoog, correct?

Yamashita: Yes. For the Dom, I only did some initial rough sketches, which included the tripod configuration.

――And the Gelgoog?

Yamashita: I just sketched the front view roughly. Io handled everything else.

――Even the backpack verniers?

Yamashita: He picked up some rejected GQuuuuuuX designs for those parts. Initially, I didn’t expect GQuuuuuuX to be so dominant in clan battles. Early on, I even considered attaching Gelgoog’s arms and legs to it. After all, if it gets damaged in battle, you could swap out parts.

――The Gelgoog’s head has three eyes; was that inspired by something specific?

Yamashita: I simply wanted to create a GQuuuuuuX-style GM face. GMs traditionally have a smooth, egg-shaped face with chevron-shaped goggles, right? In a way, that’s been Master Okawara Kunio’s signature design element since way back, hasn’t it? He’s been drawing it since the era of “Science Ninja Team Gatchaman” with the iron beast mechas and such. I think the chevron goggles are one of Master Okawara’s signatures. This is the result of trying various things while thinking that as long as I preserve that chevron shape, it should look like a GM.

――The protrusions from the back seem to be shaped with beam sabers in mind, but what are they functionally? The beam sabers themselves are mounted on the rear waist.

Yamashita: Those are actually additional sensors for general-purpose use. Realistically, the best spot for sensors on a giant robot would be the groin area, but no one wants to put them there because it conflicts with the heroic image! (laughs)

■ GUNPLA

――Tell us about designing articulation in the GQuuuuuuX with Gunpla in mind.

Yamashita: I’ve only built a handful of Gunpla myself, but even then, I noticed parts that have incredible individual mobility become constrained once fully assembled.

――Armor panels or other pieces often interfere, limiting movement.

Yamashita: Precisely. So with GQuuuuuuX, I deliberately removed bulky shoulder armor, leaving a sleeveless joint area, essentially saying, “With no armor obstruction, it should move freely.” Maybe some purist builders might call it cheating! (laughs)

――The White Gundam and Zaku each take very different approaches to articulation.

Yamashita: In that sense, the Zaku is the most restricted. GQuuuuuuX, being experimental, didn’t have strict combat design constraints, so it offered more freedom, including visible mechanical internals. With the White Gundam, my goal was offering my unique interpretation of the RX-78-2, given how extensively it’s been reimagined by others. Other mobile suits were deliberately aligned closely with established Gundam designs.

――You included internal clearances in limbs for wider mobility and single-axis joints. Was this influenced by series like AMAIM Warrior at the Borderline?

Yamashita: Actually, I just aimed for an industrial, heavy-machinery aesthetic. The AMAIM mechs join joints through surfaces and include rotating wrist and elbow joints, structurally quite different from GQuuuuuuX. That said, designing an AMAIM-style mech would interest me someday. Double-jointed designs trace back to Mamoru Nagano’s Heavy Metal L-Gaim, which featured movable frames connected by multiple arms. My generation of mecha enthusiasts saw that and thought, “This is revolutionary!” Of course, after a groundbreaking idea, there’s always pressure to innovate again. For this project, though, I consciously stepped backward, from movable frames to simpler monocoque designs.

――Even with mobile suits, the moveable frame has been mainstream since the Gundam Mk-II.

Yamashita: Visually, movable frames are excellent for scenes showing internal machinery, truly a genius innovation. Back in the ’80s, placing motors directly into joints wasn’t realistic because power units were large and heavy, requiring centralized distribution. Opening a hatch and seeing shafts everywhere felt more convincing. I still prefer that aesthetic, even if modern robotics differ.

――Robots today aren’t purely fictional anymore.

Yamashita: Modern robotics puts actuators directly into joints, making monocoque structures more practical. We’re living in an era where robots actually walk, so aligning designs accordingly makes sense.

――Though, famously, the original Gundam utilized a semi-monocoque design, and Yokohama’s moving Gundam features joint-specific motors.

Yamashita: I’ve previously said giant robots should always project slightly ahead of their contemporary era. Getter Robo reflected nuclear reactor optimism, while Mazinger Z embodied postwar material innovation with Super Alloy Z. People nowadays dismiss those classics as unrealistic, but they represented their eras’ cutting-edge sci-fi. So I feel we need to leave our own footprints or we’d be doing a disservice to our predecessors.

――Gunpla currently emphasizes HG scale kits. If given a chance for larger 1/100 kits, what would you want?

Yamashita: I’d love kits faithfully recreating cockpit details and fully detachable Core Fighters.

――Currently, the backs of these models appear streamlined.

Yamashita: In terms of setting, everything fits perfectly. Personally, I imagine a nuclear fusion reactor sits above the groin area, inside that conical piece.

――The red torso section, right? I’m looking forward to it because if reproduced in Gunpla, the Core Fighter combination should have proper consistency too. How was your interaction with Bandai Spirits during Gunpla development?

Yamashita: When I first saw the 3D-printed prototype of the GQuuuuuuX, I thought creating a Gunpla kit would be impossible. I even apologized to Director Tsurumaki, “Sorry, it’s probably impossible!” (laughs)

――I believe Director Tsurumaki said that Gundam projects and Gunpla development are synonymous.

Yamashita: I thought the complexity would doom it. Yet Bandai Spirits pulled it off in a standard 1/144 scale!

――Did you build the finished kit yourself?

Yamashita: Yes, and assembling just the head left me baffled! (laughs) Tiny pieces no bigger than fingernails littered the runners. I’m grateful to BANDAI SPIRITS that by assembling this size model kit, I could understand the mechanisms behind the “What’s the machinery inside like?” questions that tend to get omitted in robot shows.

――The aggressive foot design also surprisingly stands firm.

Yamashita: They’re using interesting plastic materials too. Slightly softer material.

――That’s KPS. It stands for reinforced polystyrene, a material that combines strength and flexibility. It’s often used in recent Gunpla joints.

Yamashita: Larger models using standard plastics might face stability issues. Possibly, the current HG scale aids stability somewhat.

――From our conversation, I feel the GQuuuuuuX has tremendous potential as a three-dimensional object.

Yamashita: Hopefully, this design encourages Gunpla builders to rethink and refresh their creativity.

――Surely it’ll inspire many modelers.

Yamashita: If robot anime becomes overly conventional or bound to tradition, it’ll stagnate.

――Rather than being treated like a traditional performance art, or being expected to follow formality and stylistic beauty, I’d prefer it to be something that shows us a glimpse of the near future.

Yamashita: Having dismantled the established framework first gives us the freedom to select fresh elements and construct the Gundam that truly speaks to our vision.

――Thank you very much for all you’ve shared.

Source: Hobby Japan, August 2025 (pages 054-057)