Over the last couple of weeks I have been tidying our attic, and while the general aim has been to prevent its contents from collapsing through the ceiling, I have a side-mission. My most valued possession when I was twelve was a Casio GD-8 Car Race watch – a digital timepiece that included a built-in racing game on its tiny monochrome LCD display. Two big buttons on the front let you steer left and right to avoid incoming vehicles and your aim was to stay alive as long as possible. I lost count of the number of times it was confiscated by teachers at my school. I used to lend it to the hardest boys in the year, thereby guaranteeing me protection against bullies. As a socially inept nerd, this was invaluable to my survival. I’m pretty sure I still have the watch somewhere, and my determination to find it has been augmented by a recent discovery: these things are valuable now.

Casio started making digital watches in the mid-1970s, using technology it had developed in the calculator market to compete on price, but as the decade drew to a close, the market became saturated and the company started to explore new ways to entice buyers. Speaking to Polygon in 2015, Yuichi Masuda, senior executive managing officer and Casio board member, explained, “Casio went back to its original thinking when it first entered the watch market; that is, ‘a watch is not a mere tool to tell the time.’ We started talking about a multifunction [approach], time display plus other things, such as telephone number memory and music alarms.”

At the time, Taito’s arcade game Space Invaders was a phenomenon in Japan. And so in 1981 Casio launched the CA-90/CA-901, a chunky calculator watch that included a sort of space shoot-’em-up but with numbers rather than alien spaceships advancing down the screen. “We wanted to create a new lifestyle of enjoying the game anywhere at any time,” said Masuda.

But wasn’t Casio also inspired by Nintendo’s Game & Watch series? After all, this iconic range of handheld electronic games started in 1980 with the juggling and catching sim Ball, and its success led to a vast array of titles, including the famed two-screen Donkey Kong that inspired the Nintendo DS. Shinji Saito, general manager and chief producer at the product planning department of Casio’s timepiece business unit, says not. “In 1980, the year before Casio launched the CA-90, Casio launched the MG-880, a game calculator that allowed users to enjoy digital invaders. Nintendo’s Game & Watch was also launched in 1980,” he says. “In developing the CA-90, Casio utilised the development assets of its MG-880 game calculator, but the starting point for the idea was Casio’s development philosophy of creating a new culture using light, thin, short and low-power technology. We were not inspired by Nintendo’s Game & Watch.”

Indeed, Casio was developing a wide array of innovative features at the time including databanks, thermometers and pulse checkers. “Their entire watch range in the 80s was huge,” says watch enthusiast Andy Bagley. “I have been collecting for years and even now I will still come across a model I haven’t seen before; there were many hundreds. I only recently discovered Casio made a range of touch screen watches in the 80s – way ahead of their time!”

Whatever the case, the CA-90 was such a success that it inspired a period of rampant creativity in the Casio R&D department. Between 1980 and 1985 the company produced dozens of different game watches – an incredible feat considering the limitations of LCD displays at the time, which couldn’t produce computer graphics or animation and simply relied on matrices of pre-set shapes that would switch on and off to suggest movement. There were several different racing games, there were shoot-’em-ups such as Heli-Fighter and Zoomnzap, and there were very rudimentary platformers including Jungle Star, where you play a Tarzan character leaping out of the way of rampaging panthers, and Hungry Mouse, where you are the mouse leaping over incoming cats.

Some were more eccentric. Aero Batics was a stunt flying game, while Hustle Monira had you helping a dinosaur catch falling acorns (as opposed to Egg Panic where you caught … falling eggs). There were even rudimentary football and golf sims. As with Nintendo’s Game & Watch titles they were often merely visual variations on very simple game design concepts. But at the time, they felt like science fiction.

Of course, Casio wasn’t the only tech company producing game watches in the 1980s. The US firm Nelsonic managed to get a Nintendo license and made watches with games based on Zelda, Super Mario Bros. and Donkey Kong, while Seiko had its Alba range of game watches throughout the 1980s, including the catchily named Y822-4000, which featured a baseball sim. The most aesthetically wild were from veteran electronic toy firm Tiger, which spent the spent the early 90s crafting gigantically chunky LCD game watches based on film licenses and arcade games such as Double Dragon and Altered Beast. Eventually however, technology and tastes moved on. After the high profile launch of the Game Boy in 1989, Nintendo swiftly cornered the portable gaming market. The game watch era was all but over.