Footage of what is claimed to be a shelved Sonic prototype has turned up. It’s compellingly awful.
CVG turned up the video on YouTube; see it yourself below.
The level was purportedly unearthed from the depths of an Xbox development kit, or possibly a debug console.
Apparently called Sonic the Hedgehog Extreme, the game looks a little similar to Riders, or to Sonic 2’s into-the-screen special stages. Shadow makes an appearance, and there’s a mission mode and battles.
The YouTube denizen responsible appears to exist solely to share footage form the game, all via off-screen shaky cam. Take it with a pinch of salt. Still, interesting stuff.