1

4 /5

It's a prototype of Sonic 3D: Flickies' Island for the Sega Mega Drive. With a build date of July 3rd, 1996, it is currently the earliest prototype of the game to be dumped and preserved.

This beta 73 build is relatively early, but largely resembles the final game. Three Zones are present; Green Grove Zone, Gene Gadget Zone (which is the second Zone in this prototype, and lacks a boss) and Rusty Ruin Zone (which has Acts 1 and 2 flipped). Completing all three Zones leads to a "To be continued" screen, after which the game resets.