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Everyone knows Mario used to be a plumber, but few realize that Game Boy’s designer used to be Nintendo’s maintenance man.

Yesterday marked the 30th anniversary of Game Boy’s release. (It was originally launched in Japan in April 1989 before coming to North America later that year.) But few stories celebrating the revolutionary handheld noted its inventor, Japanese video game designer Gunpei Yokoi, who filed for the patent for the Game Boy in 1982.

As hard as many have tried, it’s difficult to overstate the impact that the Game Boy had on Nintendo, and the gaming industry as a whole. But the coverage has shown how easy it’s been to overlook the influence of Yokoi, who passed away in 1997 at age 56.

At the time of its launch, home console systems like the Atari 2600, Nintendo Entertainment System, and Sega Genesis had already blazed trails into living rooms, worldwide. But the Game Boy was the first mainstream hit that allowed players to break free of their home’s televisions and take gaming to their bedrooms, cars, or, well, anywhere. And it certainly took video games into the future.

Game Boy was so popular that it remains one of Nintendo’s highest selling game systems ever, bested only by the Nintendo DS, another handheld, which sold 154 million units. The Game Boy sold 118.69 million units over its lifetime. By comparison, the Switch, both a console and handheld gaming device, has sold 36.87 million units to date, though it was just released in 2017. Nintendo’s best-selling non-portable console is the Wii, with 100 million systems sold.

After the Game Boy was released, Yokoi himself went on to have an illustrious career, working not only on hardware but also on game franchises like Metroid, alongside renowned Nintendo leaders like Shigeru Miyamoto.

Through the years, Yokoi’s legacy has faded, but his trajectory from maintenance worker to the designer of the Game Boy should not go overlooked.

Yokoi graduated with a degree in electronics before undergoing the job search routine many are familiar with, according to Game Over by David Sheff, which tells the history of Nintendo. That search led Yokoi to Nintendo, where he maintained assembly line machinery that made hanafuda cards, a type of Japanese playing card. “Yokoi was the entire maintenance department,” Sheff writes.

At the time, Nintendo was more of a toy company than the gaming giant it’s known as today. But it was already looking towards the future, and one day Nintendo’s then-president, Hiroshi Yamauchi, called Yokoi into his office. He wanted Yokoi to join Nintendo’s newly established “games division,” specifically to engineer something for the company to sell over the holidays.

According to Game Over, Yokoi asked, “What should I make?”Yamauchi’s response: “Something great.”

From there, Yokoi worked on many delightful Nintendo products, including the NES light gun. His band of research and design engineers were known as “a band of samurai,” Sheff reports.

And even now, decades later, Yokoi’s Game Boy remains impactful—not just helping to cement Nintendo’s legacy as a dominant video game company, but fundamentally changing how games are played.

As Game Boy Turns 30, It’s Time to Recognize Its Inventor, Nintendo’s Maintenance Man

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