Oh god. Again...

It's fake, all these hoaxes have the same rookie mistake of using the same head shading from the final game. The screens of the toy show demo have a flatter shading style, with the highlights being around the edges of his head, not the top centre.

 

Easily fake. Look at the shape of the head of the tree. In the screenshots it's rounded, in this hoax it's no different from the rest of the stem/bark.

 

Not to say I'm thinking this might be real; in fact I figure I'm as skeptical about this as anyone else. And I'd also like to point out that this is merely what I'm seeing when I look at it, and surely I don't have perfect perception. But, playing the devil's advocate here:

@Taxman: I'm not really seeing an artistic style on Sonic so markedly different as for it to be impossible to blame on the difference between how it was captured. One is a somewhat grainy and sloppy comic scan which is sharp, but very brightened and seemingly possibly a bit too contrasted; the other is captured with a blurry camera, and seems even brighter, but much more ... er, the opposite of contrasted, sorry I can't remember the word.

@Blue Blood: Actually, I'm seeing blurriness on the sides up there that looks like it might be the slight roundedness blending with the sky due to the camera.

I'm wondering about two problems, though. The guy ran pretty far and there didn't seem to be much, so where's that enemy? If I understand correctly this is a very early testing version, seems like they would put him just a little bit off to one side (seemingly off to the right) if they wanted to make sure his AI, movement, etc. was working properly. Also, if this is on a PC, why isn't he recording with a screen recorder on the machine itself, and instead using a physical camera of some kind, unless he wants to purposefully make the screen blurry and make it difficult to make things out?

 

Not a definite debunk, but this



should be the same as this



and seeing how repetitive the mountains are and how often that specific group of tiles are used here, while the circled tiles from the magazine scan are nowhere to be seen when there is a clear spot for them to appear, I am going to say that I am not convinced of the authenticity of this video.