Dec 10, 2023 15:00:00

In 'Sonic 3D Blast', why does the stage selection screen appear when you chop the Mega Drive?

The action game ``Sonic 3D Blast'' released for the Mega Drive (Genesis) in North America and Europe in 1996 has a trick that displays the stage selection screen when you chop the main unit while playing. Coding Secrets, a YouTube channel that summarizes various game tricks and programs, explains why such tricks are implemented.

Why does PUNCHING Sonic 3D trigger a Secret Level Select? - YouTube


'Sonic 3D Blast' differs from the previous Sonic series, which was a 2D scrolling action, as it is a diagonal quarter-view 3D action. In Japan, it was released in 1999 as software for the Sega Saturn under the title ``Sonic 3D Flicky Island.''

If you tap the game console while playing Sonic 3D Blast, the screen will momentarily turn black.

However, the screen soon returned and the message 'Congratulations! You have discovered the secret stage selection screen' was displayed.

The origin of this mysterious trick was the license mark ``Seal of Quality'' that was attached to software for Genesis, the North American version of the Mega Drive.

This license signifies that it has been officially approved after passing strict checks by SEGA, and the process of applying for certification and testing can take weeks, and if a problem occurs along the way, you have to start over from the beginning. It seems like it is.

If an error occurred during testing, it was sent back to the developer with a report, but if the game itself crashed, an error report stating the cause was unknown was attached, so it was often difficult to reproduce. Therefore, it seems that the game was designed to display the corresponding error screen for errors that occur while playing in debug mode.

As shown below, a corresponding error message is displayed when too many sprites are displayed or when a file fails to be unzipped.

However, in '

Mickey Mania ' released in 1994, when submitting for the Seal of Quality authentication check, instead of an error message, the message 'Mickey has discovered a time warp that leads to a secret bonus stage!' will be displayed. was programmed to. By doing this, even if an error occurs during the check, the point is that it can be pretended to be a hidden specification for the user rather than an error. If you actually select a stage from the time warp screen, a new stage will start, so the cause of the error will disappear.

The programmer's desperate plan to evade strict scrutiny was a great success, and it has since been used in other works.

This is the reason why the stage selection screen is displayed in 'Sonic 3D Blast'. In ``Sonic 3D Blast,'' the stage select screen will now be displayed when something that impedes the progress of the game occurs, such as when an interrupt occurs under certain conditions while processing the game program. It has become.

Therefore, when you chop the main body, the connection between the cassette cartridge and the main body is temporarily lost, an error occurs, and the stage select screen is displayed. This phenomenon became a hot topic on the Internet around 2017, and it became clear when the developer John Burton himself confessed how it works.