Sonic 2 Production: Level Selects and Map Sketches

This topic of discussion is on the originally intended level sequence of Sonic 2.

Here are the two versions of the level select screen;
one from the Simon Wai prototype, and one from the final.
Here is the zone loading order from the Wai proto:
00 Emerald Hill Zone
01 blank
02 Woods Zone
03 blank
04 Metropolis Zone
05 Metropolis Zone Act 3
06 Wing Fortress Zone
07 Hill Top Zone
08 Hidden Palace Zone
09 blank
0A Oil Ocean Zone
0B Mystic Cave Zone
0C Casino Night Zone
0D Chemical Plant Zone
0E Genocide City Zone
0F Aquatic Ruin Zone (Neo Green Hill Zone)
10 Sky Chase Zone

And here is the load order in the final:
00 Emerald Hill Zone
04 Metropolis Zone
05 Metropolis Zone Act 3
06 Wing Fortress Zone
07 Hill Top Zone
08 Hidden Palace Zone
0A Oil Ocean Zone
0B Mystic Cave Zone
0C Casino Night Zone
0D Chemical Plant Zone
0E Death Egg Zone
0F Aquatic Ruin Zone
10 Sky Chase

Note however that the final playing order is as follows:
Emerald Hill Zone
Chemical Plant Zone
Aquatic Ruin Zone
Casino Night Zone
Hill Top Zone
Mystic Cave Zone
Oil Ocean Zone
Metropolis Zone
Sky Chase Zone
Wing Fortress Zone
Death Egg Zone

Now on to the production maps!
(with badnik annotations)
Past

Present

Altered Present

Note: I left in the mystic cave/dust hill connection,
but dust hill may not be mystic cave

The level order I derived from these maps would be:
(Past)
Green/Emerald Hill
Ocean Wind
Woods Zone
Sand Shower
Metropolis
(Past)
Tropical (Sun) Plant
Blue Lake
Hill Top
Rock World (perhaps Hidden Palace)
(Altered Present)
Rock World (perhaps Mystic Cave)
Oil Ocean
Dust Hill (perhaps Mystic Cave?)
(Future)
Casino Night
Chemical Plant
Genocide City 1
Genocide City 2

The maps appear to follow the internal order.
However, there are zones we may have never seen
in any form; sketches, mock-ups, screens, or data.
Dust Hill shares a slot with Mystic Cave,
but they may not be the same zone.

Badnik annotations show where I think that they thematically fit,
or where they were/are known to exist.

Maps drawn and released by Hirokazu Yasuhara,
Colored by retro member Kat.