-Yu Suzuki recalls the story of the kill-switch-triggered bug behind Space Harrier’s skies

It’s not entirely uncommon for a bug to inspire legitimate features during the development of a game, and the story of an intentionally triggered bug that led to the colorful skies of Space Harrier is an entertaining example of one such inspiration.

Shmuplations has published a collection of decades-old interviews with the development team behind Space Harrier, including one with designer (and future Shenmue creator) Yu Suzuki, that explore the development of the 1985 fantasy arcade game.

In one of the interviews, Suzuki recalls how he had set up a secret switch under his desk to give the in-development game a more unfinished look whenever then-Sega president Hayao Nakayama stopped by, for fear that Nakayama would see finished graphics and assume the game was ready to ship. 

"The color of the sky was also something that came from a bug, from wiping the color RAM on the PCB. At the time, we had worked up a pretty sky background with nice color gradations… and, well, this is a little bit of a digression, but President Nakayama used to visit our office from time to time,” explains Suzuki. “The thing with Nakayama was, if he saw that the graphics were complete in your game, he would tell you it was done and it was time to release it. Nevertheless, we couldn’t just hide the game from him and show him nothing when he came by."

"So I rigged up a little switch underneath my desk. When I pressed that switch it would wipe the color RAM. You could wipe the color RAM, and it wouldn’t affect the rest of the game—everything would keep running, just the colors would get all glitched,” says Suzuki. "To a layperson, it would look like the game wasn’t complete yet. Well, one time we did this, and randomly, the colors of the sky looked extremely striking. Then I used our development tool ICE to stop the CPU and extract the color RAM data, and those became the colors we used for Space Harrier."

Suzuki says that that encounter is why the team adopted a laid-back attitude toward bugs, noting in the full interview that even the sound of bullets bouncing off of objects in-game was originally the result of a bug involving object collision.