Yep, this is where I start blurting about those other stages. Like it or not.

Wood Zone is another infamous lost level, and the only one Sonic 2 fans got to look at before it was completley removed. Its magazine pictures are EXTREMLEY rare; in fact, the only "scanned" pic I've seen so far has later been found as a hoax, and a pretty evil one, too. This is the second "lost level" in Sonic 2 Beta, and was apprently a Past (remember Sonic CD?) version of Metropolis:

The theory has orginally been concieved by Dr Zachary, and it's surprisingly correct. According to the interviews SEGA employees were forced to gi...so kindly had time to give, they got the instructions to create a forest that would later burn down and become a metalic fortress. Makes sense - look at the hollow tree trunks and compare them to Metropolis' warp tubes. By the way, Wood Zone's musci is not unique - it's from Metropolis Zone...

Since we know little else about the level, we'll just move on. It was deleted shortly after Sonic 2 Beta and apart from its palette, nothing else left from it remains in the final version of Sonic 2.

Genocide City Zone

The leader of mysterious, the phantasm of Sonic fans' imagination, the least finished named stage in Sonic 2 Beta (there are more of even less finished, but we'll get back to that later). It plays Chemical Plant music and if the Time Trave thing is really correct, it was probably its Future. Or any stage's future, for that matter - with a name like that, they should make the next Resident Evil game about it.

So, what is there to see? Er, absolutley NOTHING. O_o As soon as Sonic and Tails start the level, they are treated to a very long fall, resulting in a series of deaths (the public made up some very bad jokes about this relating to the stage's name, but I decided...not to list them =P). Game Over, back to the title screen.
The stage's multi-layered background suggests that there was more to it once before, and it was in the process of deletion in our current Beta build.

Dust Hill Zone

Yep. Dust Hill Zone. Some deluded saps say it never existed, but the name alone is evidence against that.

So, what is it, or better, what was it? It was a stage of Dust. According to reports from people working at SEGA, half of it was deserty, and half of it was wintery. O_o The striking contrast probably resulted in Sonic getting a wicked cold, so they had to remove it (<-- bad joke).

Today, all we have of Dust Hill are that picture, level slot 03 which plays the deserty Oil Ocean music and, of course, the level name found in Sonic 2 Beta stage select.

Question: a big guy with an axe told me there was no Dust Hill. That it never existed. How about that?
Ansver: a stage called Dust Hill existed at some point of Sonic 2's development and that's a FACT. The name is in the level select, and unless someone hacked it in there, it's proof that a level called Dust Hill once existed during the course of Sonic 2's development process, no matter what it was.

The Level Select name "Dust Hill" leads to Deep Caves Zone, better known to laymen as Mystic Cave, but that's much like in the case of...

Neo Green Hill Zone

Selecting "Neo Green Hill" leads to Aquatic Ruin Zone. So, it was Aquatic Ruin's beta name? Wrong. According to magazines recently found, magazines I'm not going to post here because that would be thievery, BOTH Aquatic Ruin and Neo Green Hill appeared in Sonic 2 Alpha (very early version of Sonic 2), along with Dust Hill and Deep Caves, so it can't just be a name change. The level slot is still in Sonic 2, and it's 01, right after Green Hill. So it was probably the latter's future, just like Wood Zone was Metropolis' past.

And that's all that is known about it.

(no name)

I ran out of names here. There is one more lost level in Sonic 2, and this is it. I know absolutley nothing about it - it plays Sky Chase music, but is NOT Sky Chase. It might have been the winter part of Dust Hill in a separate level slot, but your guess is as good as mine.

Note: most of these levels were deleted too early in the development of Sonic 2, but they WERE done upt o a certain point, since they feature two layers of scrolling background, whereas stages that haven't even been touched (Sky Chase, Wing Fortress) feature only one.