Namba Heavy Industries Ltd. are the secondary antagonist faction of Kamen Rider Build. They are a weapons manufacturing company known for their production of the Guardian robots used by all three nations of Japan. Secretly they plan to start a war between the nations of Japan in order to profit off of it.
In addition to manufacturing weapons, Namba also seemed to have branches in other fields such as space exploration, as they took part in Japan's Project Prominence and also mounted their own unmanned drone exploration to Mars several years prior. Namba were also the benefactors of Faust, which they fund to research the Rider System so they could weaponize it and profit off of selling it.
After the New World was built, the Namba Heavy Industry Ltd. is no longer a weapon manufacturing company but an iron factory.
At some point prior to the Skywall Incident, Namba Heavy Industries took a group of orphaned children and raised then as Namba Children, conditioning them to be completely loyal to the company and its President. These children were trained in various fields to serve as workers, soldiers and spies for the company, with several being inserted into important positions to spy on the company's behalf.
In 1995, Namba made news when they successfully sent an unmanned drone to Mars. Before the drone returned to Earth however, a piece of a mysterious extraterrestrial entity attached itself to it and traveled back to Earth along with it. There, the alien fragment slithered into the womb of Yuri Banjo, a security guard working for the company, and corrupted her unborn child with its genes, causing him to mature rapidly and Yuri to give birth after being only two months pregnant. As the child, named "Ryuga", grew, he was taken in and analyzed by Namba's researchers, who found that his DNA was irregular and was partly extraterrestrial.
In 2007, Namba Heavy Industries Ltd. collaborated with the government of Japan in Project Prominence, the first man-led expedition to Mars. After a mysterious artifact was recovered from the planet, Namba were the ones who initially held custody over it before it triggered the Skywall Disaster, in which giant walls arose from the ground and fractured the government of Japan, causing the country to be split into three separate regions called Touto, Hokuto and Seito. As tensions between the three new governments arose, Namba exploited them to sell weapons to all three of them, In 2006, Namba introduced its Guardians, a model of robot with limited AI that soon became used by all three regions as standard military and police units. Secretly, all of the Guardians were programmed with chips that would allow anyone with knowledge of a secret code to override the programming given to them by their respective government or user and manually take control.
In addition to sowing the seeds of war between the three countries, Namba Heavy Industries also served as the benefactor to Faust, a secret organization formed by several members of Touto's government to covertly run illegal and unethical experiments with Nebula Gas on human test subjects. These experiments led to the creation of the Smash monsters after a human test subject was subjected to an extreme dose of Nebula Gas, causing him to mutate into the Fang Smash. In addition to providing resources to the organization for its experiments, Namba Industries also supplied Faust's top level executives with the override code for its Guardian robots and effectively used the organization as a secret research wing. Namba also utilized Faust's agents to cover up their other criminal acts, such as having them turn a Namba Child spy into the Stretch Smash after her cover was exposed. Eventually though, after Faust's actions attracted too much outside attention, Namba ordered the research organization disbanded. Following its apparent dissolution Faust was moved to Hokuto, where it began functioning as a private research group-for-hire.
Eventually, thanks to Namba and Faust's manipulations, war broke out between the nations of Touto and Hokuto over possession of the Pandora Box. As soon as Hokuto sent all of its forces to invade Touto following a proxy battle between the two, Namba made its move. With Seito being the preferred choice of NH's CEO Juzaburo Namba to inherit Japan, Namba aligned itself with the nation to give it an advantage over the other two regions. Its a army bolstered thanks to Namba, Seito invaded and conquered the virtually defenseless Hokuto with ease. After occupying the region with its forces and taking Hokuto's Prime Minister into custody, Seito declared war on Touto next. Spearheading Seito's invasion was Kamen Rider Rogue, a Kamen Rider developed by Namba Industries and selected from several test subjects inside a Namba Industries-run concentration camp.
Seito later agreed to a 3-on-3 representative match with Touto to decide the fate of the conflict. The match would be between Touto's Kamen Riders Build and Cross-Z (as well as Hokuto's Kamen Rider Grease) and Seito's Kamen Rider Rogue, Remocon Bro's and Engine Bro's. In the first round, Grease defeated Engine Bro's while in the second, Remocon Bro's became Hell Bro's and defeated Cross-Z, leaving it up to the third round between Build and Rogue to determine the victor of the war. To ensure Rogue would win, Namba Industries took the family of Masahiro Nabeshima hostage and blackmailed their former spy Sawa Takigawa into handing over the data on Build's new forms. Transforming into Build RabbitRabbit, Build started to grasp the advantage over Rogue until Nariaki Utsumi input the data on Build RabbitRabbit into Rogue's visor, allowing Rogue to outmaneuver and beat down the heroic Kamen Rider. However, unbeknownst to Namba's staff, Build and Sawa had only leaked half the information on Build's new forms. As soon as Grease rescued the Nabeshima family, Build revealed his other form, Build TankTank, and defeated the unprepared Kamen Rider Rogue. With Seito having lost the representative match, the Prime Minister of Seito Masakuni Mido prepared to honor the terms of the agreement and relinquish the Pandora Box to be the shared property of all three nations, as well as withdraw his forces from Touto. However, after President Namba was unable to persuade Mido to ignore the agreement and continue on with the invasion, he had Blood Stalk kill Mido and transfer his face onto him. Having assumed the place of Prime Minister of Seito, Namba vowed to conquer Touto with the full power of Namba Industries.
Namba Industries supplied the Seito military with the advanced Hard Guardian robots, hoping to give it an advantage over Touto and accelerate Seito's invasion of Touto. As soon as Seito conquered Touto, Namba planned to reunify Japan under himself into an "immortal Namba Empire" and use Touto's Fullbottles to open the Pandora Box so he could use its energy source to conquer the world. Namba also developed a new type of Smash called Clone Smash, which instead of being born from humans infected with the Smash element were instead artificially engineered from scratch. With the Pandora Box still in their hands, Blood Stalk used the artifact to erect the beginnings of the Pandora Tower at the center of Japan. Stalk also informed Namba of the existence of the Evol Driver, which he stated was a device that could allow them to harness the full power of the Pandora's Box.
However, after Stalk regained the Evol-Driver to become Kamen Rider Evol and fully constructed the Pandora Tower, he revealed himself to be Evolt, the entity who annihilated all life on Mars. Though he was wary of the entity, Namba continued to remain allied with him. However, after unlocking the power of the Evol Trigger and becoming Evol Black Hole, Evolt demanded that Namba hand over control of Seito to him. Namba refused and instead sent out the Washio brothers along with a squad of Hard Guardians to take them out, only for them all to be destroyed by the immense power of Evol Black Hole. Evol then killed Namba and took control of his Hard Guardian army. Following Namba's demise, Namba Industries' assets were acquired by Faust.
After the World of Build was merged with the main Kamen Rider world, Namba Industries became a single metalworking plant, rather than the nefarious megacorporation it was in the original timeline.
- Juzaburo Namba - CEO (deceased)
- Nariaki Utsumi - Assistant / Engineer (formerly)
- Sawa Takigawa - Spy (formerly)
- Masuzawa - Spy (deceased)
- Fu Washio - Kaiser (deceased)
- Rai Washio - Kaiser (deceased)
- Kaisei Mogami - Researcher (deceased)
- Hard Guardians
- Clone Smash