Sonic 3D Blast's secret level select was actually a certification-passing trick

As many developers know, successfully moving a game through a console's certification process can be a nail-bitingly stressful experience at best. The pass itself is there to make sure a game both runs well and adheres to a handful of platform-specific rules, but unexpected bugs have a way of creeping up just when you’d least expect and throwing a wrench in those cert-passing plans.

That holds true for classic consoles as well as modern platforms, as a video shared by one developer shows. The dev in question, Jon Burton, runs through a little trick he used when developing games for the Sega Genesis to mask crashes and pass Sega's certification process with flying colors. 

Burton explains that, at first, he wrote code into his games that would display a message and a short description of the error whenever a bug derailed the game. But when it was time to send one of those games off for certification, Burton hopped back in the code and altered it to inform players they’d found a secret and would instead jump the game forward or backward a level.

So when a bug triggered the ‘secret level’, the game would load up either the preceding or upcoming level and essentially wipe the slate clean and keep it running, free of any additional errors. Burton says this worked well to get Mickey Mania through certs, so he used the same technique on Toy Story and, eventually, Sonic 3D Blast. 

Sonic 3D Blast was actually the game that prompted Burton’s big reveal. After seeing videos crop up online of players jiggling the Sonic 3D Blast Sega Genesis cartridge to bring up a secret level select video, Burton realized it was his secret bug masking method that was triggering the secret menu. 

Of course, this is all something he explains in detail in the video above, complete with game footage and peeks at his code. Burton has a handful of other interesting behind-the-scenes videos up as well over on his GameHut channel on YouTube.