Although Nintendo's lofty standing in the games industry cannot be attributed solely to a single person, it's fair to say that without the talents of Gunpei Yokoi the Kyoto firm wouldn't be where it is today. Yokoi was employed by Nintendo in 1965 and his inventions — such as the Ultra Hand and Lover Tester — would steer the company away from manufacturing hanafuda playing cards and towards the then nascent interactive entertainment industry. Yokoi was one of Nintendo's first video game designers, and under his watchful eye Shigeru Miyamoto would create Donkey Kong, Nintendo's first gaming smash hit. Later, Yokoi would create a handheld revolution with the Game & Watch and then the Game Boy — both of which became international sensations that earned Nintendo millions of dollars in revenue and helped cement the company's position globally. He is also credited with the invention of the "cross" directional pad, a feature which is used on modern controllers even to this day.

Yokoi would leave Nintendo in 1996 after more than 30 years of dutiful and fruitful service, but one of his final projects — the ill-fated Virtual Boy — would cast a cloud over his departure. He founded a new company called Koto and was approached by Japanese toymaker Bandai to assist with the production of a portable console which was intended to topple the mighty Game Boy — an ironic twist which must have raised eyebrows within the walls of Nintendo. Sadly, Yokoi would never live to see the new console hit the market — in 1997, he was involved in a roadside collision and was hit twice by passing cars, dying of his injuries two hours later.

Given the tragic background to its conception, it's little surprise that the Bandai WonderSwan attracts so much attention from retro gaming enthusiasts and Nintendo fans alike. It is viewed by many as Yokoi's most accomplished work in the handheld arena, fusing portability, control and stamina into one pocket-sized package. However, unlike fellow pretender to the throne the SNK Neo Geo Pocket, it never saw release outside of its native Japan.

The original WonderSwan was released in 1999 and boasted a 16-bit NEC V30 CPU clocked at 3.072 MHz, which left the Game Boy in the dust. It was also unique for offering two different control arrangements; it could be held horizontally or vertically, with titles like Gunpey (a Tetris-beater named in honour of the late Yokoi) and Beatmania benefitting greatly from the increased screen height in the latter mode. Eight buttons — laid out on the left-hand side of the console — permitted full control when playing vertically.

When Yokoi created the Game Boy he deliberately used a unlit monochrome screen to ensure that battery life would be decent — something that rivals Sega and Atari spurned in favour of power-hungry colour screens. By the time the WonderSwan was in development technology had come so far that the system could be powered by a single AA battery, offering an incredible 30 hours of playtime. However, to achieve this Yokoi and Bandai had to use a monochrome display, which was something of a step backwards when you consider that the Game Boy Color had launched the previous year. Bandai countered this by making the system cheap and affordable, which helped it gain some traction in what was still a highly competitive marketplace.

Just like SNK, Bandai was forced to rethink its hardware when it became clear that gamers expected colour screens in the wake of the Game Boy Color hitting store shelves. The resultant WonderSwan Color boasted an FSTN reflective LCD screen capable of displaying 241 colour simultaneously out of a possible 4096. The screen size was bumped from 2.49-inches to 2.8-inches (although overall resolution remained locked at 224 x 144 pixels) and system RAM was increased to 256 Mbit. The side-mounted power switch of the original console was changed to a button below the screen, and the overall weight was reduced — yet the battery life remains impressive, with around 20 hours from a single AA. However, one issue that wasn't solved was the lack of a 3.5mm audio jack — just like the first model, the WonderSwan Color forced players to purchase an additional accessory in order to use their headphones.

The WonderSwan Color marked something of a turning point in the console's life — not only did the console look, sound and play as well (if not better) than the Game Boy Color, but it also had some impressive support from the likes of Capcom, Namco and — most importantly — Square. The creator of Final Fantasy and one-time Nintendo stalwart had cooled its relationship with the Kyoto firm following the launch of the N64, and was keen to find another partner to work with in the portable arena. A deal was struck which would see Square remaster its early Final Fantasy titles for the WonderSwan, as well as sign-off on special limited edition bundles. Front Mission was another famous property which the studio brought to Bandai's console, and Square also created WonderSwan exclusives such as Blue Wing Blitz and Wild Card. This surge of support allowed the WonderSwan to grow its market share considerably, eating up around 8% of the total Japanese handheld market — that might not sound like much, but it's worth keeping in mind that Nintendo had practically locked out the entire sector for itself at this point.

Bandai had managed to bloody Nintendo's nose with Square's help, but it didn't last. Nintendo's announcement of the Game Boy Advance gave the firm a massive technical advantage over consoles like the WonderSwan Color, and third party publishers and developers flocked to support the new console — including Square. With its valuable ally back in bed with Nintendo, Bandai could no longer call upon its raft of exclusive RPGs to interest potential customers. The release of the SwanCrystal in 2002 resulted in the most refined version of the hardware yet seen, but even with its gorgeous TFT screen, 15 hours of battery life (again, off a single AA) and sleek, redesigned casing, it couldn't hope to compete with the GBA. Bandai pulled the plug on the console shortly afterwards, and silently retreated from the hardware arena.

The WonderSwan's status as Yokoi's final games system — twinned with its lack of release outside of Japan — has made the console very popular indeed with seasoned collectors. Despite the large number of impenetrable Japanese-language RPGs (including the famous Square offerings), the system is home to a considerable amount of highly playable releases. Capcom's Pocket Fighter and Arc System Works' Guilty Gear Petit (1 and 2) are fine examples of handheld brawlers, while anime tie-in One Piece: Grand Battle Swan Colosseum is arguably one of the best looking titles on the console. Capcom would also contribute entries in its Mega Man and Ghosts 'n Goblins series (released as Rock Man and Makaimura in Japan), while Namco released a Tekken card-battling game and a sequel to the PlayStation platformer, Klonoa. Sure, there are a lot of Gundam and One Piece titles in the WonderSwan's library that are only likely to appeal to completists, but the console's reputation as being import-unfriendly is largely unfounded; provided you're willing to spend the high prices being asked for its best games, there's plenty of quality content to be had even if you aren't able to read Japanese.

What makes the WonderSwan even more interesting today is the wide range of peripherals released for the console. The WonderWave allowed communication with a Sony PocketStation via an IR link, while the MobileWonderGate took the console online. Possibly most interesting of all is the WonderBorg, an insect-like robot which could be programmed using the WonderSwan itself. Finally, the WonderWitch encouraged bedroom coding by giving people the tools to make their own software on a PC, and then write it to a flashable WonderSwan cartridge. Interestingly, the winner of the 2001 WonderWitch coding competition — vertically-scrolling shooter Judgement Silversword — actually got a commercial release and is now one of the most sought-after and expensive WonderSwan games.

As if to underline the WonderSwan's growing popularity with collectors, the SwanCrystal has gone from being almost worthless to a seriously expensive investment. Shortly after Bandai ceased production, brand new SwanCrystal systems could be obtained from Japan for around $30-$40, but now the same consoles have been known to fetch much higher prices, while unboxed variants sell for close to $100. Both the monochrome and Color iterations are considerably cheaper, but it's recommended that you opt for the SwanCrystal. The black and white unit's screen suffers from ghosting — and is obviously incompatible with Color software — while the WonderSwan Color's display is incredibly dark and almost impossible to see unless you're standing under a light. You might have to pay more to get the optimum WonderSwan experience, but it's worth it in the end.

Had Gunpei Yokoi not been tragically killed at the age of 56, who knows what projects he and his team at Koto would have moved onto. His influence can be felt in Nintendo systems like the DS, which personifies his "Lateral Thinking of Withered Technology" approach, where existing tech is used in new and interesting ways. It's a crying shame that we'll never get to see what kind of amazing gaming ideas Yokoi could have come up with after the WonderSwan, but those who have lived with and enjoyed this excellent little handheld will attest that it's a fitting send-off for one of the greatest designers the game industry has ever known, and arguably one of Nintendo's most important employees.