Prototypes for Four Sonic Games, Including SA2 & Sonic 1, Released

Hidden Palace, a video game preservation and archival group, has released prototypes for Sonic Adventure 2, Sonic Spinball, Dr. Robotnik’s Mean Bean Machine, and Sonic 1 to the public. These prototypes show what these games were like months before they were completed and released. This gives us insight into the game’s development, often featuring content that was cut or altered in the final release.

The Sonic Adventure 2 prototype is among the most notable of the new prototypes. It represents the earliest complete build of the game that’s been found, dated to May 7, 2001, well over a month before it shipped. According to Hidden Palace it features some significant differences from the final release, although they didn’t detail it in their announcement article.

The Sonic Spinball 16-bit prototype is the first complete one to surface in around 20 years. Though it isn’t the oldest, it does still feature some minor differences from other previously-released prototype build, including an options screen and the ability to beat the game. Again, the differences between this and the final release were not detailed.

Dr. Robotnik’s Mean Bean Machine is, likewise, a later-in-development prototype build then what’s already available, but it also marks the first time a prototype of the game has been released in years.

Finally, they showed off a new prototype of Sonic the Hedgehog 1 on their stream as I was typing this. Among the differences from the final build are balls in Green Hill that can be pushed around, and UFOs in the skies of Marble Zone. Starlight Zone is also called Sparkling Zone, and has stars in the background instead of mountains and a cloudy sky.

These elements were seen in early screenshots from the game as well as some footage discovered earlier this year, but this is the first time it’s been found in a playable build. Going by the stream, the prototype is not complete, and appears to be missing later acts in bosses in stages beyond Green Hill.

Saturns or UFOs dominate the sky in the protoype’s Marble Zone

 You can checkout the Sonic 1 stream, which is still running as of 5:25 EST, at the Hidden Palace twitch channel here. You can also find footage of other prototypes there.

You can download the first three prototypes and check them out for yourself from the Hidden Palace website here. As of this writing, Sonic 1 is not available, though that will presumably change shortly.

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Nuckles87 has been an editor at Sonic Stadium since 2007, and has been covering events like E3, PAX, and SDCC since 2010. An avid retro gamer, he runs a monthly stream on Twitch where he explores obscure Sonic oddities, and how aspects of the franchise have evolved over the decades.