[The following was provided by forum moderator and researcher JenHedgehog.]
Sonic Retro member Orengefox recently acquired three new Sonic Game Gear prototypes, which have now been made available for download. These are review copies of Tails Adventures and Sonic Labyrinth, and an early demo of Sonic the Hedgehog 2 (all obtainable here.)
Sonic 2 is a rolling auto-demo showcasing mainly the prototype version of Green Hills Zone, which was prominently shown in many early magazine articles prior to the game’s release. Sky High Zone and Underground Zone can also be seen. The auto-demo has a time stamp of Dec. 5, 1991, making this an extremely early version of the game that was compiled almost a year before the final version was released.
As well as the Game Gear games, Orengefox is releasing some other new Sonic demos including a previously unseen Japanese Sonic Adventure trial, and a trial version of Sonic & the Secret Rings[forum link] which was distributed in limited quantities to competition winners in Japan.
To see what our members are able to find hidden inside these games once the digging begins, head over to the forums, where all these prototypes can be downloaded right now.
Retro user Orengefox posted on the forums his discovery of two Japanese prototypes of Sonic Adventure and Sonic Adventure 2 on Sega Dreamcast. Both of which have a potential source of content that are missing from the final builds with the Sonic Adventure Auto Demo showing some good promise.