This week saw the passing of Kan Yabumoto, creator of Gottlieb’s Mad Planets arcade video game. Very sad news indeed – Kan was well-respected and admired by all who knew him. As a game designer in the early eighties, he was one of the behind-the-scenes unsung heroes of the Golden Age of video gaming – and you could be forgiven for having not heard of Yabumoto-san.

The environment and management structure of early eighties Gottlieb, meant that any promotion of the games’ actual designers was frowned upon – mostly due to paranoia about them being poached and lured away by the larger video game companies, where placing superstar programmers on a pedestal was actively encouraged. The likes of Eugene Jarvis (Defender, Robotron) and Dave Theurer (Missile Command, Tempest) were achieving rockstar-like status within industry circles during this time. Despite being owned by Columbia Pictures (who in turn were owned by Coca Cola) the company viewed itself as a somewhat small fish in a big pond. Gottlieb wanted to shroud its programmers in secrecy – especially with Coin-Op heavyweights Williams and Midway just down the road in Chicago.

So ridiculous was the situation, that a request for an interview with a games magazine in April 1983 was only granted on the condition that the three programmers being interviewed were named D Ziner, J Walkman and R Teeste. These guys were actually Q*Bert’s designer Warren Davis, sound engineer David Thiel and graphics artist Jeff Lee. And yet, in the same issue of the magazine, Eugene Jarvis of Williams Electronics was pictured and named.

But Kan wasn’t driven by fame and money. He got satisfaction from programming tight code that just worked, and was extremely humble about his creative achievements. That’s not to say he didn’t have a mischievous side. On Mad Planet’s default in-game High Score table, Kan placed his 3-digit first name as the top score – KAN, and spelled out his last name – YABUMOTO vertically down the left side of the initials!

This was his way of ensuring that his legacy was attached to Mad Planets. Gottlieb’s management team had no clue.

The game itself was met with modest success – a run of approximately 1,400 cabinets were built, and Mad Planets was generally very well received. It is certainly now regarded as something of a cult classic in arcade gaming circles. These non-Atari arcade gems are worth seeking out amongst the throng of better-known titles from the same era.

Looking back at the game he recently said:

I’m proud that the program I wrote (in assembly language on a 8088 CPU) was bug-free, and many enthusiasts loved the game even though the company produced only a humble number. Still, I’m very happy that my efforts (of over one year on this project) achieved a modest success while many other projects never made production.

In Mad Planets, the player assumes control of a spaceship and must destroy a series of planets appearing from the centre of the screen. The longer they are left without being destroyed, the larger they become. At their peak size, planets will form moons orbiting around themselves. Destroying these moons causes the planets to literally go “mad”, and start targeting the player’s ship directly. Other features in the game include the opportunity to rescue stranded astronauts found floating around some screens. Here’s some great game play footage:

To me, Mad Planets is one of those rare titles that elicits an element of joy when you find one. It just screams “PLAY ME!”. Its finest feature is its control layout (I seem to have a thing for complex control systems for some reason). Consisting of a full eight-way joystick with trigger button to move the ship around and shoot, and a separate spinner to rotate the craft, simply tackling the game requires a deep breath and a few practice runs to get the feel of the player interface:

Mention should be made of the artwork. Gloriously eighties:

When you play the game, you realise it has that perfect mix of compelling gameplay, amazing sounds, artwork that pops right out of the cab, and a deep rule set that you are compelled to discover and get through. The game draws you back time and again:

Easy to learn, difficult to master.

It was clear that Kan was very proud of his creation:

I considered my activities in writing code, checking and debugging the program, and designing the game’s actions as a form of communication with the game players who would eventually experience what I put into the game. I always paid extra attention in the “fairness” of the game. When the bullet touches the enemy, or your spaceship gets very close to an enemy object, the program has to make a judgement (in a very efficient way due to the limited number of clock cycles that can be allotted in each activity like that) that is always on the player’s side. The program made sure that the contact of the enemy object to the spaceship had to be “overlapped” significantly before calling it a collision. When a comet (a little wiggly object) appears on the screen, it always chooses the farthest quadrant to enter the scene — the player has at least a half-screen of distance to prepare and evade the contact. Otherwise, when the spaceship is near an edge of the screen, it could be hit from the behind with no time to react — this would be completely unfair. With these (and many other subtle) points carefully implemented, I had to deliver the “fun” of playing the game which was not easy. The introduction of the astronaut-rescue was one key factor that broke the boredom in playing the game. Maybe, there could have [been an] additional stage of action of some kind to enrich the game (such as another form of enemy object or friendly something). Even adding the astronaut-picking was a time-consuming effort. The truth is I was pretty much exhausted at the end.

I guess this deep attention and understanding to what players might feel and experience in a game, made Mad Planets such a great joy to play back in 1983, and still to this day.

But Kan’s influence went much further at Gottlieb. Without him, it could be argued that Q*Bert would never have happened. In an interview with Coinop.org back in 1995, Warren Davis, who worked alongside Kan recounts the early development process of his game:

I was new to Gottlieb in 1982 and had “learned the ropes” by helping one of our programmers with his game. I was looking for a game of my own to do when I saw that another programmer, Kan Yabumoto (who would later do Mad Planets), had filled a screen with hexagons that consisted of 3 differently colored diamonds. If you chose the colors right, each hexagon seemed to be a 3-dimensional cube. Kan had filled the screen to its edges with this pattern, but for some reason, when I looked at it I envisioned a lot of the hexagons removed so it looked like a pyramid of cubes floating in space.

So a cursory glance at Kan’s screen one day in the office, sparked something in Warren’s mind. That spark led to what would become the seminal arcade title Q*Bert.

I caught up with Warren earlier this week, and we discussed Yabumoto’s legacy:

I thought of him as an atypical game designer. He seemed more of a scientist and engineer than a “creative” type. But Mad Planets was a beautifully realized game, which showed us there was more to him than met the eye. We also worked together at Pixelab, the company he founded with Jun Yum, hardware designer at Gottlieb. Jun and Kan were the company. I worked part-time with them and was grateful for the opportunity. Pixelab developed the hardware (and with my help the software) for Premier Technologies’ only video game system. It was a joy to work there. I will cherish the memory of those days and of Kan. He is very much in my thoughts and will be missed.

Kan lived quite the full life. After studying agricultural chemistry at Tokyo University, he migrated to the US and continued his studies at UC Davis in California. From there he took a course in computer science at DePaul University in Chicago. A job at Kraft Foods soon beckoned. Warren also mentioned a discussion with Kan about this:

I remember him talking about his days at Kraft Foods, He wouldn’t reveal the ingredients in their American Cheese slices, but I recall him saying that none of them were cheese!

(Having tried those slices some ten years ago on a self-catering holiday to the USA, can I just say that my suspicions are now confirmed).

Presumably somewhat unfulfilled by the intricate world of manufactured consumer cheese products, he took a job at Gottlieb in 1982 to be a part of the new craze of video games, and created his masterpiece, Mad Planets. More recently, after being relatively active in writing software via his company Pixelab, including the widely used File Management Utility XX Copy, Kan returned to his native Japan to settle, and was a very proficient player of the Japanese board game Go in his spare time.

(A great nugget here: Kan actually bought his own Mad Planets cabinet in 1986 from an arcade, and held onto this same machine for a good 30 years until he moved back to his homeland!).

So our thoughts go out to Kan’s family and friends – I am sure he will be fondly remembered. For the rest of us, Mad Planets lives on for us to enjoy and appreciate his creative genius. Thank you Yabumoto-san.

Tony