Sonic & Knuckles Zones

This is a sub-page of Proto:Sonic the Hedgehog 3.

At this point in development, the Sonic & Knuckles Zones that entered production (with the exception of Flying Battery and the Bonus Stages) have been removed from the game, although some data remains for them.

General#

• With the exception of Flying Battery (which technically is between Carnival Night and IceCap), all of the levels between Mushroom Valley and The Doomsday reuse Launch Base's title cards. Additionally, any levels after The Doomsday show no title card.
• There's unused title card mappings, palette pointers and collision pointers for said zones, however they're all blank.
• Unless otherwise noted, all Acts are assigned their intended music.

Mushroom Valley Zone#

This zone has been mostly removed from the game at this point.

• The level is titled "Mushroom Valley" in the level select. This early name is still used in the final game, but it was renamed Mushroom Hill in Sonic & Knuckles.
• As soon as you spawn in, Sonic and Tails die.
• Early versions of the badniks exist, and can be placed in debug mode.
• An early version of the Hey Ho miniboss is implemented.
• A decompression error corrupts nearly all the graphics. A fix is provided below.
• Uses Azure Lake's graphics and color palettes. Leftover palette data unique to this prototype exists, which is documented below.
• An object layout is intact for both Acts, but it doesn't fit the later Sonic 3C 0408 prototype Mushroom Hill layouts.
• Some unique background scrolling code is still intact.
• There's listings for level art, however they don't point to anything.

Decompression Fixes#

• 04A8D0:46EE - MVZ ACT1 decompression fix (Part 1)
• 04A8D4:46EE - MVZ ACT1 decompression fix (Part 2)
• 04A8E8:46EE - MVZ ACT2 decompression fix (Part 1)
• 04A8EC:46EE - MVZ ACT2 decompression fix (Part 2)

Unused Color Palettes#

Unused color palettes can be found at offsets 0x1F2F0E, 0x1F582A for Act 1 and 0x1F2F6E, 0x1F588A for Act 2. These color palettes are identical for both Acts and don't match any of the palettes used for the final game. It's fairly close to the Sonic & Knuckles palette, but it has a number of differences.

• The HUD/object palette line has some coloring errors; the brightest white is a yellowish orange, the final's orange is a brighter cyan, and the blue is instead black.
• The walls appear to have somewhat turquoise shading in this build, while the final is more olive green. The darkest shade is mistakenly white, but the final's shade seems to fit the prototype colors more.
• The object mushrooms are dark yellow instead of bright red.
• The third-brightest wood orange matches that of the final Act 2's autumn palette, while the final Act 1 has a slightly darker shade.
• The sky uses a somewhat richer shade of cyan, while the final copies the object line's shade.
• The brightest yellows in the final's background line are instead cyan and blue respectively.

A re-imagining of how Mushroom Valley may have looked. This screenshot is taken from the Sonic 3C 0408 prototype using this prototype's color palettes.

Layout Differences#

To do: Actual comparisons. Fix MVZ 1103 maps.

Mushroom Valley Zone Act 1 Map

November 3rd (only object layout)
Sonic 3C 0408

Mushroom Valley Zone Act 2 Map

November 3rd (only object layout)
Sonic 3C 0408

Flying Battery Zone#

Flying Battery is in a very preliminary state, lacking animated tiles and many objects. As in the final version, it is listed in the level select after Carnival Night, suggesting that this is an old leftover.

Proto	Level Select Icon

• The background is different, and matches the design seen in the zone's unused level icon. Oddly, the palette in the icon is a bit more blue. It additionally always uses the indoor background even in outdoor sections, and features "EGG" capsules not present in the final.
• The background isn't set to loop. As a result, the background becomes more broken as you progress.
• The Act 1 boss position matches that of the final Sonic 3 and the Sonic 3C 0408 proto.
• Act 2's layout is even less complete.
• The Barrier Eggman boss isn't in the level. Its object does exist within the data, though. The boss arena also exists, although the boss itself locks the screen much higher for some reason, possibly left over from an earlier layout.
• Act 2's boss position matches that of the final Sonic 3.
• Act transitions are not present.
• There are color palette cycles listed for both Acts, but they are empty. Perhaps the lights in the background could have been intended to animate.

Unused Chunks#

To do: There's a lot of unused chunks left. Chunks that were altered in 0408 onward.

The unused background chunks, once combined, look like this.

Layout Differences#

• Both acts have a row of rings at the top of the level. It's unknown what they are used for.
• The animated tiles do not animate and instead use placeholder numbers.
• You can't swing on monkey bars as they aren't implemented.

Flying Battery Zone Act 1

November 3rd
Sonic 3C 0408
Final (Sonic & Knuckles)

• Some parts of the level are similar, but some parts are completely different.
• The overscan color is teal.

Flying Battery Zone Act 2

November 3rd
Sonic 3C 0408
Final (Sonic & Knuckles)

• Some parts are completely different.
• Again, the overscan is teal colored.

Originally, the bridge where you fight the end boss was part of the foreground layer, and the crumbling section inbetween bosses was stored in the background layer. The plan may have been to use the background collision flag like the rising floor segments in Marble Garden Zone and Sandopolis Zone, but later versions reverse this, and the crumbling section is now on the foreground layer, while the bridge and everything past the end capsule is on the background layer.

The final game doesn't use the background collision flag at all, and the solidity for the bridge is provided by an invisible object that matches the background layer's movement. This allows the bridge to carry the player horizontally as it moves, something which doesn't happen out of the box with just plain terrain collision. That may have been what necessitated this change.

Flying Battery Zone Background

Proto	Final (Sonic & Knuckles)

• Slightly different:
  • EGG Capsules are smaller and lighter.
  • There's some tubing in the background, and there are lights.
  • The white lights in the background are nearly identical to the Sonic & Knuckles version.
  • The parallax scrolling isn't done yet.

Lava Reef Zone#

Proto	Proto (Restored)

Lava Reef is normally broken upon loading, but it's possible to make it playable by forcing the game to load leftover data from an earlier build, which just so happens to contain all of the necessary data for Act 1. The only data that is missing is collision. The prototype contains a set of six identical maps for Act 1 and one map for Act 2, which both have differences, there are seven complete maps and two identical map fragments. Unfortunately, no graphical data for Act 2 is present in the ROM.

Act 1 seems to be the most intact of the Sonic & Knuckles Zones, having a full layout prepared for it, albeit completely lacking objects.

• The level's palette is completely different from the final.
• The pipes were completely redrawn and replaced in later builds.
• The upper-right path was shrunk down in the final game.

Full Maps

• 0x1EB85E LRZ2
• 0x1EC4CE LRZ1
• 0x1ED2F6 LRZ1
• 0x1EE11E LRZ1
• 0x1EEF46 LRZ1
• 0x1EFD6E LRZ1
• 0x1F0B96 LRZ1

Fragmented Maps

• 0x1EAF4A LRZ1
• 0x1F3EC4 LRZ1

Download Sonic 3 (Nov 3, 1993 prototype - LRZ1 restored) File: Sonic 3 (Nov 3, 1993 prototype - LRZ1 restored).bin (2 MB) (info)

Download Sonic 3 (Nov 3, 1993 prototype - LRZ2 restored) File: Sonic_3_(Sonic_3_Nov_3_1993_prototype_-_LRZ2restored).bin (2 MB) (info)

Color Palettes#

Act 1		Lava Reef Zone color palettes 0x1F58EA (Act 1) and 0x1F59AA (Act 2).
Act 2		A color palette for Lava Reef Act 2 is located at 0x1F594A or 0x1F302E. This color palette does not match well with any known version of Act 2. However, a few of the colors are recognizable to the final version, albeit arranged very differently.

Background#

Act 1 Background

Proto
Final (Sonic & Knuckles)

The lava channels, far-end cavern hollow background, and Death Egg were redrawn. The coloration is also more blue-green in the prototype.

• The HUD uses an incorrect palette here. The second palette line apparently has not been defined and is only using a single color in place of white.

Unused Chunks#

Act 1:

Act 2:
Although the map contains several unused chunks, these may have been intended for the boss area.
1D, 1E, 32, 82, 86, 99, A8, A9, AA, AB, AC, AD, AE, AF, B0, B1, B2, B3, B4, B5, B8, D4, D5, D6, D7, D8, D9, DA, DB, DC, DD, DE, DF, F0, F1, F2, F3, F4, F5, F6, F7, F8, F9, FA, FB, FC, FD, FE, FF.

Layout Differences#

Lava Reef Zone Act 1 Map

November 3rd
Sonic 3C 0408
Final (Sonic & Knuckles)

Lava Reef Zone Act 2 Map

November 3rd using S&K dataset and palette, with chunk IDs shifted/remapped
Sonic 3C 0408
Final (Sonic & Knuckles)

Unimplemented Zones#

The remainder of the main Sonic & Knuckles Zones all use placeholder data from Angel Island, indicating that the levels proper weren't yet implemented into the game.

Act 1	Act 2

There are still some interesting things to look at in here, as level data isn't the only part of what makes a Zone. Note that all of these levels still use the placeholder entries in the final version of Sonic 3.

To do: Most of this could be compacted into a single table, and it'd allow to document the start points in a sensible way. The music is also already documented in a separate section.

Sandopolis Zone#

• The Act 1 boss is coded into the game, and can be spawned through hacking. Behavior is a little different from the final and it cannot be defeated.
• The music is only slightly different from the final.

Sky Sanctuary Zone#

• While the title card reuses Launch Base's, the Act number is missing. This is because the hardcoded Zone check in the title card code is already implemented.
• The music instrumentation is quite different.
• Act 2 oddly uses Death Egg Act 1's music. This is likely the result of the Death Egg's track being right after Sky Sanctuary's.

Death Egg Zone#

• The music is almost identical to the final.
• Both Acts use Act 2's music.

The Doomsday Zone#

• Much like Sky Sanctuary, the Act number is missing.
• The music has different instrumentation on a few parts.
• Technically has a title card, however it's just Launch Base's (it's placed here so that the Sonic & Knuckles zones show title cards at all).

Zone ID $0D#

• In the final version of Sonic 3, Act 1 of this Zone is used as a dummy slot for loading in the stage data instead of the intro cutscene data when skipping the intro cutscene in Angel Island Act 1. This special case isn't yet implemented in this build, so both Acts of the Zone are still using the default placeholders.
• Unlike the final game, this Zone lacks a title card.
• Uses the Special Stage music, much like the final game.

Zone ID $16#

• Act 1 was later used for Lava Reef Act 3 or Lava Reef's boss.
• Act 2 was later used for Hidden Palace.
• Both Acts play the Special Stage music, like the final game.

Zone ID $17#

• Act 1 was later used for Death Egg Zone's boss.
• Act 2 was later used for the alternate Hidden Palace that is accessed through a big ring in Sonic & Knuckles.
• Both Acts use the Special Stage music, like the final game.