From Game Developer Research Institute
The same year there was Marble Madness, there was a fun little game called Xyzolog...or is that Xyxolog? Roll your ball over red blinking things while avoiding the green spinning things.
Fortunately, you can destroy the green things by making yourself explode. Unfortunately, this uses up lives. But if you hit enough enemies in one shot, you can rack up a big bonus. You gain a life each stage.
I was able to confirm this was designed by Taito and developed by Compile. I wonder if Taito was planning on making an arcade version.
Fun Fact: Xyzolog is a boss in Taito's arcade game Syvalion. 
How did they get Namco's Starblade onto the Sega CD? Some folks on the Sega-16 forums tried figuring out how it worked here.
But the big question for me is, who developed the Sega CD version? According to Japanese sites, Technosoft did it and some Super Famicom pachinko games for Telenet Japan. I guess this would be the start of Namco and Telenet's relationship. The earliest mention of the Starblade/Technosoft thing I can find is a 2001 2ch post.
Despite being ported to numerous platforms, Mountain King isn't considered the classic I think it perhaps should be. A lot of people don't seem to remember it. But rather than try to write about it myself, I'll let others do it and do it better. Please read this and this, then come back.
I will say the animation makes a difference in gameplay. The original Atari 8-bit and 5200 versions are much smoother than the 2600 and ColecoVision conversions done by VSS.
The 2600 version contains something referred to as "Glitch Heaven," a glitchy "hidden level" up in the sky. Ed Salvo of VSS: "The secret level in Mountain King was a feature of the 800 game and I duplicated it." However, the 8-bit/5200 versions do not have a "Glitch Heaven;" they have a "Glitch Hell" (see video below).
Mountain King was originally written by Bob Matson. Jess Ragan (author of one of the posts above) e-mailed him and managed to get a response, which you can read here. Matson now works at Michigan State University.
Available for Atari 8-bit computers, Atari 5200, Atari 2600, ColecoVision, Commodore 64, and VIC-20
Your mission is to fly the Dante Dart through the Cryptic Computer and destroy its four Failsafe Detonators (marked "6507") before the Computer self-destructs. Watch out for forcefields, missiles, bats, and other obstacles, and keep an eye on your energy, shields, and time until detonation.
Even more obscure is the Atari 8-bit computer version, available only on the Imagic 1-2-3 compilation disk which also contains Quick Step and Wing War. The graphics are better, and the layout is a little different. No longer restricted to a single Computer, you travel from planet to planet (Computer to Computer?), each one containing a single Detonator. It's kinda like Gradius, or that's what people on the Internet say.
2600 version by Dan Oliver
TIP: To speed things up, fly to the right side of the screen.
REMEMBER: Pins on the Detonators may be booby-trapped!
The last licensed game for the Sega Genesis in North America. What better way to send off one of the all-time great consoles than with one of the all-time great arcade games?
Okay, so the Genesis didn't exactly go out with a bang here, but it's an exact replica of the arcade version, right? Well, not exactly. I talked to programmer Scott Marshall a while back, and he shared some information about the development.
Marshall used the Genecyst emulator to develop the game. He also mentioned a backdoor, but I couldn't get it to work: at the player select screen, hold down C and press right nine times.
So it's not arcade perfect. So no new features were added. But if you want Frogger action on your Genesis/Mega Drive, this is it. At least the music wasn't butchered. (The GBA version on Konami Arcade Advance comes to mind.)
It is first-person, but it is not a shooter. It is an adventure where all elements work in unison to weave an interactive tapestry for the senses. A veritable feast for the mind, body, and spirit.
More to the point, Tunnel Runner is a first-person maze game in which you must find the exit while avoiding the Zots, ghastly creatures not at all like the ghosts in Pac-Man. Sound cues increase in volume as they draw near. You can play with random or pre-programmed mazes.
Of course, it's not enough to find "the" exit. You have to find the key and the right door, one of five kinds, all of which do different things.
I enjoy this game and it is technically impressive, but some might be turned off at first by the navigation. You don't move a step at a time. You run until you reach a corner or a door or stop to check the map, which you'll be doing often. And in later levels, you'll find that map isn't too helpful.
Honors. All those highfalutin words in the opening paragraph are completely justified as Tunnel Runner was a nominee for inclusion into the Smithsonian's The Art of Video Games exhibition. It lost out to Pac-Man in its category, but it's nice to see a relatively obscure game get some respect.
Development. Tunnel Runner was programmed by Richard K. Balaska Jr. at CBS Electronics. He also worked on the RAM Plus chip inside the cartridge that helped make this game possible.
No, it's not the Eggo waffles video game - it's a "fowl" Kaboom! knockoff (which itself was a knockoff of Atari's Avalanche).
I'm probably one of the few people, even among 2600 fans, that think this is the better game. With the paddle controllers, you make a blue bear catch eggs coming out of a weird-looking bird hellbent on your destruction. After each successful wave, you shoot the eggs back at him. The game is over when you're drowning in yolk.
That slight variation in gameplay is one reason I prefer Eggomania. Also, games last longer. I find that Kaboom! gets too difficult too quickly.
The music and graphics are pretty charming as 2600 games go. The bird is well animated. If you miss an egg, he does a victory dance to a little ditty. If you shoot him, he's stripped down to his boxers and floats up to Heaven.
Eggomania was developed by James Wickstead Design Associates, one of the more prolific contract developers of the early 1980s. Wickstead Design is still around today, providing product design and development services.
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