Proto:Sonic the Hedgehog 3

This page details one or more prototype versions of Sonic the Hedgehog 3.

  This prototype is documented on Hidden Palace.

Download Sonic the Hedgehog 3 (Nov 3, 1993 prototype) File: Sonic the Hedgehog 3 (Nov 3, 1993 prototype).bin (2 MB) (info)

This page or section needs more images. There's a whole lotta words here, but not enough pictures. Please fix this.

To do: Find the differences between the final and early tracks. Rip and compare sound effects. Early level-layouts for the rest of the maps in the leftover data. Other changes Try to apply the leftover data

The November 3rd, 1993 prototype of Sonic the Hedgehog 3 was dumped on November 16, 2019, as the finale of Hidden Palace's Sonic Month. It is the first and currently the only true prototype of Sonic 3 to have been discovered, as all previous prerelease ROM images match the final. Although the EPROM labels claim a date of 3 November 1993, the ROM header suggests the data is actually from October.

The October date makes sense, given that this build is wildly incomplete for a game that was supposed to be finished by the end of November. It was made at a time where the game was starting to be split into two separate games. Differences include early sprites, palettes, character abilities, missing Act transitions, and different music that would later be repurposed for the Sonic & Knuckles Collection on PC. Flying Battery Zone (which was moved to Sonic & Knuckles) is still present by default, and Lava Reef also exists deep within the ROM. It's also horrendously buggy, especially in regards to music.

The prototype seems to be the same one that was showcased in Sega Magazine in December 1993, given that all of the screenshots are 1:1 matches of what's seen in this prototype.

Notes

• While the EPROMs date the ROM to November 3rd, the header suggests that it was built in October.
• Leftovers from Star Trek: The Next Generation, and even earlier builds of Sonic the Hedgehog 3 linger at the end of the ROM.
• The prototype is region free, unlike the final.

Gameplay Differences

• Sonic has a Drop-Dash-esque move that can be performed by jumping while pressing Up.
• Elemental shields lack their specific effects.
• Special Stage rings aren't present.
• The insta-shield isn't present yet.
• Even though sparkles appear above checkpoints when Sonic has 50 rings, the bonus stages are inaccessible through normal play.
• It's very easy to clip into walls due to unfinished collision.
• Tails will fly instead of swimming when attempting to fly underwater and is also capable of carrying Sonic underwater.
• Tails cannot get tired from flying or swimming.
• Super Sonic has been partially implemented, and has the ability to shoot rings, which was removed from the final.
• The demo of Angel Island Zone Act 1 is a bit different, and also desyncs.
• The debug mode "animation test" accessed by pressing B + C in debug mode has not been implemented.
• Many stage transitions have not been properly implemented yet, so the level select is required to continue to the next zone in most cases.
• Objects that Sonic can hang onto still act like Wing Fortress's from Sonic 2 in that Sonic won't curl into a ball when jumping off, and his animation stays the same.
• Overall, the Competition Mode levels are more complete than the single-player ones and even feature the final game's player sprites. There are still some things that were changed, however.
  • The Grand Prix and Time Trial modes (as well as the monitor options) do not exist as a result of a lack of menu for the mode.
  • The prototype features little markers near the black line that show the positions of the two players. They often change between three sprites for unknown reasons. These were removed in the final game, yet their sprites still exist within the data.
  • The lap counter uses the blue/yellow palette of the "TIME" text, instead of the final's red/white palette.
  • It's possible to complete a lap by jumping over the goal post.
  • The game will declare a GOAL at lap 6 rather than the final's lap 5, but the race never ends. As a result, races can go all the way up to Lap 9, which results in it rolling over to 0 and continuing from there.

Super Sonic

Coding for Super Sonic exists even though the Special Stages haven't been created yet, thereby preventing you from gaining any Chaos Emeralds. He can only be accessed by destroying an S monitor. Most of the code is reused from Sonic 2, with a few adjustments: the invincibility music plays instead of using a unique track, and the palette cycling has been adjusted to only use three colors in Sonic's palette instead of the four colors that Sonic 2 required. However, the actual colors used are still based on Sonic 2's palette format (Where the darkest blue in Sonic's palette is indexed first, followed by progressively lighter shades of blue) instead of Sonic the Hedgehog 3's format (Where the lightest blue color is indexed first, followed by darker shades). As such, the palettes for both Super Sonic and Sonic's palette after the transformation runs out are glitched.

Graphical Differences

• Sonic and Tails' sprites are the same as the ones in Sonic 2, albeit updated for Sonic the Hedgehog 3's palette with some new sprites.
• Fire shields always overlap the player.
• The HUD numbers have some shading that were removed in the final. The shine on the HUD text is also larger.
• Neither Sonic nor Tails have victory poses, instead they use their "hurt" sprites upon finishing an act.
• The bubble shield uses simpler graphics compared to the final.
• The invincibility stars are missing, but they do show up using the fire shield's graphics if the player has a fire shield.
• Some frames for the lightning shield haven't been positioned properly.
• The game-over graphic is still the Sonic 2 sprite, and thus looks incorrect with the palette used in Sonic the Hedgehog 3.
• Title cards for levels use a different palette, and graphics from the stage load early, making the title cards garbled after a few seconds.
• A majority of object palettes are not finalized.
• The Speed Shoes and Heavy Shoes icons in Competition mode have different icons:

November 3rd	Final

Audio Differences

Between Sonic the Hedgehog 2 and Sonic the Hedgehog 3, the sound driver was completely replaced. In this prototype, the replacement driver is in an early state where it hasn't had features from the previous driver re-implemented yet, and it seems to suffer from some glaring bugs. There are also some other general differences.

• Sounds often bug out and sustain until either the game is paused or something else plays on that sound channel.
• Various objects don't play the correct sound effect:
  • The underwater "alarm" sound uses a completely different sound - likely just an incorrect ID assignment.
  • Many bosses don't play sounds. This includes explosions, zooming, etc. They play one sound when being defeated.
• Collecting a ring only plays the sound for the right speaker, and doesn't alternate between the ones for the right and left (despite both sounds being present).
• The Spin Dash plays the rolling sound, much like Sonic the Hedgehog Genesis as well as some of the Sonic 2 prototypes.
• Playing a theme that would interrupt the stage theme prevents it from reloading.
• Beating an act doesn't play the act-clear jingle, it instead continues playing the stage theme.
• The Speed Shoes play the invincibility theme rather than speeding up the music - and it does not cut back to the level music when the effect ends.
• The Sonic the Hedgehog 3 miniboss theme does not exist in this prototype. In the slot $2E, where the final Sonic the Hedgehog 3 miniboss theme would be, this prototype contains an SMPS rendition of the unused theme from the PC version.
• The Sonic & Knuckles miniboss theme, located at sound test slot $18 in this prototype and the final release of Sonic 3 alone, plays when fighting minibosses instead of using slot $2E.
  • A small remnant of this exists in the final game while fighting the bosses in Hydrocity Zone; leaving the water while the drowning countdown plays will result in the Sonic and Knuckles miniboss theme playing instead of the Sonic the Hedgehog 3 one. This was fixed in Sonic the Hedgehog 3 & Knuckles with the Big Shaker fight, but not with the Robotnik one.
• Interestingly, certain tracks are Genesis compositions of their themes in Sonic & Knuckles Collection, suggesting those may have been originally intended to be used instead of the final tracks. The MIDI tracks in that rerelease often match up better with these early music versions as well, indicating that all the MIDI music was likely ported from a prerelease build rather than the final game where available.
• The pieces of music which are recognizably the same tunes as those in the final Genesis release, rather than entirely different tracks which were used in the PC version, still contain some differences.
  • Some instrumentation in nearly all of them is noticeably different from the final. Specifically, the instruments used for Angel Island act 2, both acts of Flying Battery, both acts of Mushroom Valley, Lava Reef act 2, Sky Sanctuary, Doomsday, Balloon Park, Desert Palace, and Chrome Gadget are audibly different, likely because the sounds used there in the final are unfinished and may not even exist yet.
  • The Angel Island Zone act 2 theme is missing a few notes.
  • The Doomsday Zone theme seems to be incomplete, as its Square/Saw Wave instrument sound is likely meant to be quieter.

Sound ID	Name	November 3	Final	Sonic & Knuckles Collection
$01	Angel Island Zone Act 1
$02	Angel Island Zone Act 2
$07	Carnival Night Zone Act 1
$08	Carnival Night Zone Act 2
$09	Flying Battery Zone Act 1
$0A	Flying Battery Zone Act 2
$0B	IceCap Zone Act 1
$0C	IceCap Zone Act 2
$0D	Launch Base Zone Act 1
$0E	Launch Base Zone Act 2
$0F	Mushroom Valley Zone Act 1
$10	Mushroom Valley Zone Act 2
$13	Lava Reef Zone Act 1
$14	Lava Reef Zone Act 2
$15	Sky Sanctuary Zone
$1A	The Doomsday Zone
$1C	Special Stage
$1F	Knuckles' Theme
$21	Balloon Park
$22	Desert Palace Zone
$23	Chrome Gadget Zone
$26	Sonic the Hedgehog 3 Credits
$29	Act Clear
$2A	1-Up
$2D	Competition Menu
$2E	Unused		(No equivalent music is in the final game.)

Notes

• The song used for the level select ($2F) does not glitch after listening to it for an extended amount of time, unlike in the final version of Sonic 3.
• The unused theme from the PC game is also present as slot $2E, which is where the Sonic the Hedgehog 3 miniboss theme is in the final release. In Sonic & Knuckles and Sonic 3 & Knuckles, this slot contains a duplicate of the Sonic & Knuckles miniboss theme, which is used instead of slot $18 to play music for the minibosses. This renders slot $18 unused in all final retail releases of Sonic 3, Sonic & Knuckles, & Sonic 3 & Knuckles except for Sonic & Knuckles Collection.

Title Screen

November 3rd	Final

The title screen uses some very, very basic graphics. Specific visual differences include:

• There's no background at all - the final adds a nice skyline of Angel Island Zone. This also means no Tails or Tornado.
• The palettes appear to be broken in some fashion. The logo banner is changed from a light blue/white to a red/white color scheme, and the logo itself was changed from dark blue with orange outlines (the way the text was presented on the box art for previous titles) to yellow with dark blue outlines. There's also no TM next to the banner.
• The model for the ring and Sonic himself seems to be the same as the final, but the ring's positioning as well as the lighting were updated. The final render makes better use of the color space, since it dithers colors where the proto render doesn't. Sonic also isn't animated, though the banner still bounces up and down. The rest of his body is present below the ring, unlike the final.
• Incidentally, the text reading "Sonic the Hedgehog" below the logo is finalized - this simple text carried its way into the final build of the game.
• The Copyright 1994 SEGA text is absent, which is likely more of a given.
• Entering the button combination Up, Up, Down, Down, Up, Up will enable Debug Mode.
• There are no menu options. Pressing Start automatically sends the player to the Level Select.
• Using the patch code FFFFD0:0000 will disable Level Select. Doing so will allow the game to immediately start on Zone 1 as in Sonic 1 and 2. This does not disable the soft reset (pause, A) or frame advance (pause, B) functions, however.

Playing as Tails or Knuckles

You can play as different characters by pressing the following button combinations at the title screen:

• Sonic + Tails: A + Start
• Sonic alone: B + Start
• Tails alone: C + Start

You can also play as different characters by using the cheat codes FFEF4C:000X FFFF08:000X FFFF0A:000X and replacing the X with one of the following numbers:

• 0 - Sonic & Tails
• 1 - Sonic
• 2 - Tails
• 3 - Knuckles (will use Tails' sprites instead)

Tails and Knuckles have graphical problems with their end-level Sign Posts they beat a level, however;

Tails' Sign Post	Knuckles' Sign Post

• When playing as Tails, the Sign Post will display an image of a blue Knuckles instead of Tails' image.
• Knuckles has data in the game and his name card is still present, though when playing as him the Sign Post will load Dr. Robotnik's image instead of Knuckles' image.
• When playing as Knuckles, the player object doesn't correctly set the collision plane when spawned, making navigating the stages very difficult. Setting memory address FFB046 to 0x0C will fix this.

(Source: TCRF & Sonic Retro)

Level Select

The level select is almost the same as the final game. It plays no music, rendering the File Select theme unused.

Just like in the final game, none of the S&K zones are selectable by default (with the exception of Flying Battery Zone). Unlike in the final game, all bonus stages are accessible (the last 2P VS act goes to the gumball machine, while the two "Bonus" acts go to the Sonic & Knuckles bonus stages). The PAR Codes below can be used to regain access to these zones.

Zone	Act 1 Code	Act 2 Code
Mushroom Valley Zone	005C0E:0700	005C10:0701
Sandopolis Zone	005C12:0800	005C14:0801
Lava Reef Zone	005C16:0900	005C18:0901
Sky Sanctuary Zone	005C1A:0A00	005C1C:0A01
Death Egg Zone	005C1E:0B00	005C20:0B01
The Doomsday Zone	005C2A:0C00	005C2A:0C01
ID 0D	005BF2:0D00	005BF4:0D01
Lava Reef Zone Act 3/Boss	005BF6:1600
Hidden Palace Zone	005BF8:1601
Death Egg Zone Final Boss	005BFA:1700
Hidden Palace Zone (Special Stage Ring)	005BFC:1701

Each level can be played through the level select. Lava Reef Zone, Sky Sanctuary Zone, and Death Egg Zone are accessible using the first, second, and third 2P VS options respectively while The Doomsday Zone uses the Sound Test option. The gumball machine bonus stage can be played by selecting "Bonus" on the level select. "ID 0D" can be accessed by selecting Angel Island Zone Act 1 and 2. Lava Reef Act 3 and Hidden Palace Zone can be played by selecting Hydrocity Zone. Finally, the Death Egg Zone final boss and Hidden Palace Zone (Special Stage Ring) can be accessed through Marble Garden Zone Act 1 and 2.

Stage Differences

Angel Island Zone

To do: Layout and object differences

• The intro features Sonic riding a surfboard into Angel Island Zone. In the final game, Sonic rides the Tornado, jumps off, and turns into Super Sonic. The object still exists in the final game, but goes unused.
  • The only way to see this intro is if you wait on the title screen for the demo. Getting into Angel Island Zone Act 1 normally does not play the intro.
  • Knuckles also has completely different sprites, and simply blocks Sonic's path instead of punching him out and stealing the Chaos Emeralds. Because they share the same palette, Knuckles also causes the HUD to turn green; the developers fixed this in the final by coloring his socks yellow.
  • Outside of the intro cutscene, this version of Knuckles can also be seen during gameplay, standing a short ways in front of the player at the beginning of Angel Island Act 1. He leaves after a few seconds of standing and gesturing. If the player walks forward before he leaves, he glitches out when the player gets near him. The exact way in which he glitches varies; if playing as Sonic, he turns blue, and if playing as Tails, he turns into a mass of incorrect tiles.

These Knuckles sprites, possibly before he was redrawn to be more in-style, are completely different from the other cutscene sprites used throughout the game.

• Tails does not seem to spawn into the level for a while, aside from flying above the first badnik. The player can be airlifted by Tails, interestingly.
• A fire shield and badnik right before the miniboss are missing.
• Underwater countdown timer graphics do not load correctly.

• In the debug list, there is a strange object that seems to test sprite scaling. It causes some very adverse effects on the game, its level collision, and its VRAM.
• In one of the upper alcoves early in the level, there are 2 static monitors that hurt the player when broken. These were replaced with monitors containing Power Sneakers and 10 Rings in the final game.
• The area before the miniboss has a few tiles incorrectly placed.
• The miniboss cutscene is slower, rougher, and the miniboss plays a different sound when launching missiles.
• The second part of Act 1 loads much more slowly, leading to some garbage object graphics at first.
• The waterfall platform objects do not play any sounds.
• Act 1's boss arena has the decorative flame objects like final, but they load incorrect graphics.
• During the tunnel to the end of the level in Act 2, you can see for a moment when the flying ship graphics are loaded.
• Eggman's "whooshing" sound when he goes through the trees at the end is completely different.
• The sound that plays when Eggman burns the bridge is different.
• The boss palette tends to cause issues with rings.
• Even if you jump off the bridge while Knuckles destroys it, you still go to Hydrocity Zone anyway.

Angel Island Zone Act 1 Map

November 3rd
Final

Angel Island Zone Act 2 Map

November 3rd
Final

Unfinished cutscene

In addition to the surfboard cutscene, an early version of the final intro does exist in the prototype ROM, as shown in the embedded video. It can be enabled using the PAR codes 003CC6:0003 and 003CC8:5AD2. There are a few differences:

• Some of the graphics are glitched.
• The Tornado doesn't bob up and down while flying.
• The final Knuckles object is present in addition to the prototype one. However, he doesn't jump up to uppercut Sonic, which softlocks the game because it leaves the player unable to move.

Hydrocity Zone

November 3rd	Level Select Icon

• The background in Act 1 is completely different from the final game, featuring gray bricks and pillars, waterfalls, and rows upon rows of plant life. This early background design can still be seen in the level select icon for Hydrocity Zone in the final game.
• Sonic and Tails do not play their falling animations when entering the level.

No animation plays for the fall into HCZ.

• After dying, the background does not seem to load properly.

Game having problems with loading background at higher elevations after death in inner Hydrocity Zone.

• The giant fan object does not play any sound.
• When Sonic runs across water, there is no sound associated.
• The Buggernauts use different graphics.
• The grabbing hand booster object plays no sounds.
• The Turbo Spikers play no sounds.

• There are some misplaced spikes in Act 1.
• Destroying a Blastoid causes the player to bounce back the other direction as if they hit a boss.
• The 3D-like effect of the water doesn't work properly towards the middle of the level.
• The Big Shaker's underwater palette is incorrect.
• If Sonic is twirled around by the miniboss, he uses his death-animation instead of his floating animation.
• When the miniboss enters, no sound is played.
• The "whooshing" sound is played more frequently when the miniboss causes a whirlpool.
• The drowning miniboss music bug exists in this prototype, but it plays IceCap Zone Act 2's track instead of the Sonic & Knuckles miniboss theme.
• Some walls in Act 2 use slightly different sprites during the wall crusher segment.
• The wall crushing segment plays no sound.
• Sonic will play his previous animation when jumping on a spinning cylinder.
• Rings overlap tubes.

Layering issue with rings and tubes.

• Knuckles is blue when first loading in.
• The boss overwrites the water surface graphics.
• Trapdoor objects have issues with sprite priority.

To do: Screenshot

• There is a section in Act 2 involving a vertical bar object that is unused in the final game.
• The Knuckles cutscene is very different and unfinished - he immediately charges towards Sonic upon seeing him, which in turn presses the button and makes the bridge collapse in under a second.
  • The small wall between the two also doesn't stop Knuckles from running, which results in him floating in air near Sonic.
• The pathway to the boss has no objects.
• Act 2's music has issues with volume.
• After defeating the boss, the level music does not start back up.
• In the final version, the level includes a couple of swinging balls and water droplet objects as eye candy. The proto lacks this, making the level look rather bland.

This ornamental tower is only in the final version.

‎

Unused Chunks
Hydrocity Zone Act 1

• 

  ID DF A colorful mosaic? This is really too colorful to see in Hydrocity.

Hydrocity Zone Act 2

• 

  ID 28

Hydrocity Zone Act 1 Map

November 3rd
Final

Hydrocity Zone Act 2 Map

November 3rd
Final

Marble Garden Zone

To do: Object & Layout differences

• The player doesn't start up in the sky.
• The drillbot enemy seen throughout the level does not play any sounds when drilling.
• Tails seems to be able to influence the spinning top object when both he and Sonic are on it.
• The spinning top object doesn't fall out of the level when hitting a dead end.
• The chain with spike ball object plays no sound.
• The spinning wheel object makes no sound.
• Neither Sonic nor Tails have animations for grabbing pulleys, instead continuing whatever animation they were playing before grabbing on.
  • The "switch" sound plays when grabbing the pulley.

• There are some misplaced rings in Act 2.
• It's possible to see below the level in Act 2.
• When the player encounters the Act 2 boss, the background is buggy. The player also dies when they hit the bottom of the screen, so two-player Tails must be used to start the fight properly.
• The game lags a lot during the Act 2 boss, and it's possible to stand on the air.
• Like with Hydrocity Zone, there's no transition to Carnival Night Zone.

Marble Garden Zone Act 1 Map

November 3rd
Final

Marble Garden Zone Act 2 Map

November 3rd
Final

Carnival Night Zone

Sound ID	Name	November 3	Final	Sonic & Knuckles Collection
$07	Carnival Night Zone Act 1

• Both acts use a completely different music track. MIDI renditions of these songs would go on to be used for the same zone in Sonic & Knuckles Collection (although Act 1 is in a different key).

• The Act 1 boss arena has no walls.
• Once the Act 1 boss is beaten, there's no way to progress further without using the level select.
• The underwater palette is very different, identical to the one seen in early screenshots.
• Knuckles doesn't appear in Carnival Night Zone Act 2 at all, which results in the blackout and subsequent flood never happening, as well as Sonic falling to the ending area of Knuckles' Act 2. It is possible to get to the intended boss arena via Tails, though.
• The capsule at the end of Act 2 is not present.
• Touching one of the spinning cylinders as Tails will crash the game, possibly due to the game trying to load incorrect/missing graphics.

Carnival Night Zone Act 1 Map

November 3rd
Final

Carnival Night Zone Act 2 Map

November 3rd
Final

Flying Battery Zone

Flying Battery Zone is in a very preliminary state, lacking animated tiles and many objects.

November 3rd	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 and as a result, the background becomes more broken as you progress.
• The Act 1 boss position matches that with Sonic the Hedgehog 3 Alone and Sonic 3C 0408.
• 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 leftover from an earlier layout.
• Act 2's boss position matches that with Sonic the Hedgehog 3 Alone.
• Act transitions are once again 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.

Flying Battery Zone Act 1

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

Flying Battery Zone Act 2

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

Flying Battery Zone Act 1 Background

November 3rd	Final (Sonic & Knuckles)

Flying Battery Zone Act 2 Background

November 3rd	Final (Sonic & Knuckles)
200px	200px

IceCap Zone

|$0B |IceCap Zone Act 1

|

|

|

|- |$0C |IceCap Zone Act 2

|

|

|

|-

• Both acts use a completely different music track. MIDI renditions of these songs would go on to be used for the same zone in Sonic & Knuckles Collection. Act 1's appears to be unfinished at this point due to missing drums and a general lack of polish.
• Sonic begins the stage running down the mountainside. In the final, he snowboards down it.
• The "trap" glitch (in which the game treats the vertical screen wrap position as a bottomless pit under specific circumstances) affects both playable characters at this stage in development. The final version of the game fixed it for Sonic, but Tails would be stuck with it until Sonic the Hedgehog 3 & Knuckles.

• There are some misplaced ice spikes in Act 2.
• Though the tunnel leading to Launch Base Zone is present, the game does not actually send the player there like in the final game.

IceCap Zone Act 1 Map

November 3rd
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Final

IceCap Zone Act 2 Map

November 3rd
Final

Launch Base Zone

|$0D |Launch Base Zone Act 1

|

|

|

|- |$0E |Launch Base Zone Act 2

|

|

|

• Both acts use a completely different music track. MIDI renditions of these songs would go on to be used for the same zone in Sonic & Knuckles Collection (although the MIDI version of Act 1 is in a slightly different key).

November 3rd	Final

• The background has a different palette, resulting in a bluer ocean, a somewhat pink sky (not unlike Act 2) and a greenish Death Egg with darker supports. Much like Hydrocity Zone and Flying Battery Zone (initially), this palette would show up in the final game in Launch Base Zone's level select icon.

• The player does not start by launching through the snow.
• Knuckles' palette and sprites mess with some objects.
• Some animated tiles are missing.
• The building doesn't collapse, though the transition to the boss still works.
• There are four warp tubes in the Twin Hammer boss arena, two on the floor and two on the ceiling. Entering a floor tube will warp the player to a corresponding ceiling tube.
• The top of Act 2's background is buggy.
• Jumping on the first floating platform encountered in Act 2 triggers a series of FM chirps. This can be found in a few other areas of the level. This does not seem to be found as a playable value in the sound test. Instead, this appears to be a bug related to jumping out of the water while only partially submerged.
• Part of the first Act 2 boss is overlapping the foreground.
• Knuckles stands on a bridge. The animated tiles also disappear for some reason.
• After a certain point in the cutscene, Sonic freezes, making it impossible to beat the stage.

Water Level

Just like the final version, the water level is disabled, but intact. To activate it, follow the same directions as in the final version of Sonic 3.
Unlike the final version, these color palettes are greenish. The final version uses a copy of Launch Base Zone Act 2's palette with a few minor changes.

‎

‎

Launch Base Zone Act 1 Map

November 3rd
Final

Launch Base Zone Act 2 Map

November 3rd
Final

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.
• Reuses Launch Base Zone's title cards. This happens for the rest of the levels until The Doomsday Zone, with a few notable changes here and there.
• As soon as you spawn in you die for no reason.
• 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 Zone layouts.

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

A re-imagining of how Mushroom Valley Zone may have looked. This screenshot is taken from the Sonic 3C 0408 prototype using this prototype's 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 completely different from any of the palettes used for the final game. One color is wrong here, the brightest white, causing rings and the HUD to look incorrect.

Mushroom Valley Zone Act 1 Map

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

Mushroom Valley Zone Act 2 Map

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

Sandopolis Zone

• Almost the same as it is in Sonic the Hedgehog 3 Alone.
• However, the Act 1 boss is implemented, 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.
• Act 2 uses the Angel Island Zone Act 2 palette. This is also true for other zones that use AIZ graphics.

Lava Reef Zone

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

Download Sonic_3_(Sonic_3_Nov_3_1993_prototype_-_LRZ2restored).bin File: Sonic_3_(Sonic_3_Nov_3_1993_prototype_-_LRZ2restored).bin (2 MB) (info)

(Source: Drx)

To do: Rip the leftover maps using offset addresses in the list below and try to find out the differences.

A re-imagining of what Lava Reef Zone Act 2 may have looked like. This uses the early layout and an altered prototype palette to fit the final graphics.

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. The only data that is missing is collision. The prototype contains a set of 6 maps for ACT1 and 1 map for ACT2, which apparently contains some differences, there are 7 complete maps and 2 fragments.

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

Color palettes

Act 1		Lava Reef Zone color palettes 0x1F58EA (act 1) and 0x1F59AA (act 2).
Act 2		An odd color palette that may have been intended for use for Lava Reef Act 2 is located at 0x1F594A or 0x1F302E. This color palette does not match well with any known version of Lava Reef Act 2. However, some of the colors are recognizable to the final version, unlike the Sonic 3C 0408 prototype version, albeit arranged differently.

Background

November 3rd	Final (Sonic & Knuckles)

(Background, Map Rips: evilhamwizard)

The lava channels, the far-end cavern hollow background, and the Death Egg were redrawn.

• 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 Chunk
Lava Reef 1

Only a single chunk is not used to compose the map. ID 7E.

Lava Reef 2
Although the map contains several unused chunks, these may have been used 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.

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/colors, with chunk IDs shifted / remapped
Sonic 3C 0408
Final (Sonic & Knuckles)

Sky Sanctuary Zone

• While the title card reuses Launch Base Zone's, it also happens to be missing the act numbers. This seems to indicate that the rest of the S&K zones had proper title cards at one point.
• The music instrumentation here is quite different.
• Act 2 oddly uses Death Egg Zone 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 Death Egg Zone Act 2's music.

The Doomsday Zone

• Much like Sky Sanctuary Zone, the act numbers are missing from The Doomsday's title cards. It still claims to be Launch Base Zone, though.
• The music here has different instrumentation on a few parts.

Zone ID $0D

• This zone lacks a title card, in the final version of Sonic the Hedgehog 3 it simply said "Zone".
• The Blue Spheres special stage music is used here.
• Act 1 uses AIZ intro graphics, whereas in the final it uses the standard level graphics.

Azure Lake Zone

• The background is a little different.

Balloon Park Zone

• The music is composed differently.

Desert Palace Zone

• One of the background palette's colors is incorrectly set to black instead of brown.
• The music here is also composed differently.

Chrome Gadget Zone

• The background scrolls differently.
• The music here is also composed differently.

Endless Mine Zone

• The large breakable gold nuggets aren't there.

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 Zone.
• Act 2 has a bug that causes the Launch Base Zone Death Egg graphics to load midway through the level.
• Both acts play the Special Stage music.
• There is no title card.

Zone ID $17

• Act 1 was later used for Death Egg Zone's boss.
• Act 2 was used for the alternate Hidden Palace Zone that is accessed through a big ring in Sonic & Knuckles.
• Both acts use the special stage music.
• There is no title card.

Gumball Machine

Incredibly bare bones at this point in development, but a start has been made.

• Plays the Special Stage theme.
• The map only features a layout - there's no collision detection for the walls, the gumball machine itself doesn't do anything, and most importantly, there aren't any bumpers, meaning you unceremoniously fall... to your death, as the code to end the bonus game isn't present. The tiles for the spring net are present(!) and are even a different color(!!), but alas, there's no springs atop them, nor does said net have any collision itself.
• There's some different graphics, namely in the tileset for the walls - the final has more shading details. The background is filled with placeholder tiles instead of the finalized checkerboard, and the layer in front of it is quite different in design. The gumball machine itself is more or less finalized, however.
• This level lacks a Bonus Stage title card.
• The HUD still has SCORE and TIME listed, unlike the final version of Sonic the Hedgehog 3.

Glowing Spheres

• Even less complete than the Sonic 3C 0408 prototype.
• The stage's background does not exist in the ROM, and instead uses placeholder number tiles. These numbered tiles are intended to be animated by a seemingly not yet present reloading routine.
• The Bonus Stage title card is missing.
• The HUD still has SCORE and TIME listed, unlike the final version of Sonic the Hedgehog 3.

Slot Machine

• The Bonus Stage title card is still missing.
• The HUD still has SCORE and TIME listed, unlike the final version of Sonic the Hedgehog 3.

Background graphics with animations

November 3rd	Final

• The slot machine in the November prototype is quite bare-bones, lacking several details that would appear in the final game.
  • The simple hole that operates the slot machine was replaced with an elaborate glass cage.
  • A bunch of shading was added to the blue area, as well as connections between the shapes and the central cage. The top shapes were shifted down to accommodate the top-most shade.
  • On the topic of the squares and triangles, they had their colors changed to a cycling yellow palette.
  • The indigo color used by the slot machine was updated to a proper blue.
• The protoype's second palette is missing the colors needed for Rings, which is obviously a problem. The colors in the object palettes had to be shuffled around to accommodate both the Rings and the updated slot machine...

November 3rd
Final

• ...which would result in the slots themselves losing some of their details.
• A layout is present, but collision has not been implemented.

Special Stage 1

The Special Stages are tech demos at this point in development, using different sprites entirely for the spheres. No proper gameplay has been implemented however, other than manipulating the spheres. Holding A and pressing Start will return you to the Title Screen.

Special Stage 1 features a pre-rendered gray sphere, with red spheres rotating around it. These set of spheres do remain in the final game in Angel Island Zone Act 1, however they are unused.

Button	Control Pad 1	Control Pad 2
Start	Toggles between automatic and manual rotation.	Toggles between automatic and manual rotation.
A/C	Rotates left or right.	Zooms the spheres in or out. A zooms out, C zooms in.
B	Resets the spheres to their point of origin.	If automatic movement is enabled, stops the spheres from rotating along one of the axes if held down.
Up/Down	Adjusts how fast the spheres rotate on one of the axes.	Moves the matrix up and down.
Left/Right	Rotates the spheres along the Y-axis	Moves the matrix up and down.

Special Stage 2

Special Stage 2 features a flat square of spheres bouncing up and down while rotating. A secondary animation causes them to contract and expand. Parts of this animation overload the VDP's sprite bandwidth, causing some of the sprite pixels to disappear (as can be seen in the expanding animation below).

Button	Control Pad 1	Control Pad 2
Start	Toggles between automatic and manual rotation.	Toggles between automatic and manual rotation.
A/C	Speeds up or slows down the rotation when automatic, or rotates the spheres left or right along the X-axis when manual.	Zooms the spheres in or out. A zooms out, C zooms in.
B	Toggles between the primary and secondary animations.	If automatic movement is enabled, stops the spheres from rotating if held down.
Up/Down	Rotates the viewing angle in the given direction.	Moves the matrix up and down.
Left/Right	Rotates the viewing angle in the given direction.	Moves the matrix up and down.

Special Stage 1	Special Stage 2

Unused Objects and Enemies

ID	Offset	Name	Description
12	0001C6A0	LBZ Platform	A glitched platform that appears to belong to LBZ.
1A	0001DFCE	Speed Cannon?	A seesaw-esque object that forces Sonic to run extremely fast upon pressing the jump button. It seems to belong to LBZ.
1C	0001E6C6	Spinning Spike?	A very strange object that appears to be spinning. It seems to belong to LBZ.
1D	0001C228	Grabbing Platform	One of the LBZ platforms, but with a "grabber" underneath that can hold Sonic. Its tile mappings appear to be somewhat glitched.
84	00040704	Hey Ho	A very glitched version of Hey Ho, the Mushroom Valley Zone Act 1 boss.
90	00049FB6	Fireworm?	Fireworm badnik for Lava Reef Zone. Crashes the game while trying to DMA non-existent sprites.
91	0004A29C	Iwadomoki	The exploding "fake stone" badnik. Can crash the game.
92	0004A400	Toxomister	The smoke clouds do not hurt Sonic, they only slow Sonic down.
93	000495CC	Madmole	The mushrooms it throws have an exaggerated effect on Sonic. It appears in the Mushroom Valley Object Layout.
94	000499BC	Mushmeanie	The bouncing mushroom enemy from Mushroom Valley Zone.
95	00049B24	Dragonfly	Flies up and down, as in the final game.
96	00049DCA	Butterdroid	Butterfly badnik from Mushroom Valley Zone.
97	00049E50	Cluckoid	Chicken badnik from Mushroom Valley Zone.
98	0004107E	Sandopolis Golem	The miniboss from Sandopolis Zone.
B6	0003CE96	FBZ2 Barrier Eggman	The mid-boss of FBZ Act 2. Although coded, it isn't actually placed in the stage.
C5	0004178A	Hidden monitors that can be revealed by the falling signpost.
CA	00035AD2	Sonic during the AIZ intro sequence.

Unused Graphics

Possible early graphics for a button used by Knuckles. These tiles are loaded early on in the space used for the burning Angel Island Zone stage graphics.

Compressed graphics in 0x182624 contain Tornado plane sprites, indicating that the cutscene with Sonic surfing would be removed soon.

A smaller version of the Turbo Spikers. This was found in an unreferenced Konsinki Moduled-compressed archive at 0x132802.

Act Clear Signs

Early
November 3rd 1993 and Final

In Sonic 3, the sign frames are uncompressed and loaded dynamically over each other to conserve video memory. This said, also present in the game's data is an unused copy of the same art compressed like in Sonic 2, strongly suggesting it is from earlier in development.

Although Sonic, Tails, and Robotnik are basically the same as their Sonic 2 counterparts, Knuckles appears for the first time, with a slightly different appearance relative to the final art. This early version is still present in the final game, as well as in Sonic & Knuckles.

Unused Palettes

Hydrocity Zone Act 1 underwater

Original	Alternative 1	Alternative 2
		0x1F53AA

Hydrocity Zone 1

Original	Alternative 1	Alternative 2

Hydrocity Zone 2

Original	Alternative 1	Alternative 2
		0x1F534A

IceCap Zone Act 1 and 2 "Cavern Area"

Original	Alternative 1	Alternative 2
		0x1F554A

IceCap Zone Act 2 "Outside"

Original	Alternative 1	Alternative 2
		0x1F55AA

Mushroom Valley Zone Act 1 and 2

Original	Alternative 1	Alternative 2
		0x1F582A and 0x1F588A

Lava Reef Zone Act 2
Although the color gradients are disorganized, these color palettes, oddly enough, are the same as the final version rather than the Sonic 3C 0408 prototype.

Original	Alternative 1	Alternative 2
	0x1F302E	0x1F594A

Balloon Park Zone This palette matches the final icon's colors.

Original	Alternative 1	Alternative 2
		0x1F5B2A

Chrome Gadget Zone

Original	Alternative 1	Alternative 2

This palette shows an otherwise unseen part of the background, and also matches the final icon's colors. {clear}}

Angel Island Zone 1 "Used in an early cutscene?"

Original	Alternative 1	Alternative 2
		0x1F5C4A
		An unused AIZ1 color palette appears to be a mix between the beach cutscene and the forest interior, as if the forest background did not exist. This color palette has been removed in the version used by the prototype.

Data Leftover

Data Leftover Listing with the location of data leftover from other rewrites of old builds during development.

Towards the end of the binary, two partial blocks of older data exist, which contain Lava Reef Zone data and older palettes (and potentially other levels' data), among other things. The palette block used in-game is the one on the left.

0x1E96D4 (Used)	0x1F25AE (Very Old)	0x1F4E6A (Old)
The prototype main color palette array, a large majority of which are referenced and used. It does not contain the palettes for Mushroom Valley or Lava Reef.	The oldest group of unused palettes. Hydrocity's bricks have orange/purple colors, and the outside palette for Ice Cap Act 2 does not exist. The Mushroom Valley and Lava Reef palettes are still present, and of all the Competition zones, only Azure Lake has an entry.	Another group of unused palettes. Mostly similar to the previous one, except Hydrocity now has the final brick brown shades, an early version of Ice Cap Act 2's outdoors palette exists, and more of the Competition zones have palettes with only Endless Mine still missing.

Source Code

Pieces of another game's source code (judging by the labels, most likely the aforementioned Star Trek game) can be found scattered throughout the ROM at the following locations.

0xAFF0E:

                          ,WhichMessage
                Bra     @DoneInput

@InComingHail:
                Move.w  #3,WhichMessage
                Bra     @DoneInput

@ImpulseDamaged:
                Move.w  #4,WhichMessage
                Bra     @DoneInput

0xBFAB4:

                                                                  the screen.

DMAScrollArrows:
                Subq.w  #1,ArrowDelay                           ; Determine if arrow buffers or blanks should
                Bne.s   @NoTogg                                 ;  be DMA'ed this makes the arrows flash.

                Move.w  #15,ArrowDelay                          ; Reset delay between flashes.
                Eor.w   #1,ArrowToggle                          ; Toggle between blanks and arrows.

@NoTogg:
                Tst.w   ArrowToggle                             ; Branch to relevent bit.
                Beq.s   @ArrowsOff

; ====== Arrows on, DMA the buffers. ======

                Lea     UpArrowBuffer,A0                        ; Source.
                Lea     ScrollBBase+(27*2)+(21*64),A1           ; Destination.
                Move.w  #1,D0                                   ; Number of words.
                Move.l  #VDP_VRAMWrite,D1                       ; Set to write to VRAM.   
                Moveq   #2,D2                                   ; Auto increment.        
                Jsr     PushDMA                                 ; Move characters to VRAM.

                Lea     DownArrowBuffer,A0                      ; Source.
                Lea     ScrollBBase+(27*2)+(26*64),A1           ; Destination.
                Move.w  #1,D0                 

0xCF970:

                Lea     ScrollBBase+($b*64)+(27*2),A1
                Jsr     Word_2GVRAM    
                Move.w  #AsciiOffset+CHR_Palette0+CHR_HighPri,D5 ; Color is different if in impulse.

                Bra     @DoneSeperators

@NotImpulse:
                Move.w  #AsciiOffset+CHR_Palette3+CHR_HighPri+'.',D0        ; Place decimal points and '/' seperators.
                Lea     ScrollBBase+($5*64)+(28*2),A1           
                Jsr     Word_2GVRAM     
                Lea     ScrollBBase+($7*64)+(27*2),A1
                Jsr     Word_2GVRAM     
                Lea     ScrollBBase+($d*64)+(28*2),A1
                Jsr     Word_2GVRAM     
                Move.w  #AsciiOffset+CHR_Palette3+CHR_HighPri+'/',D0  
                Lea     ScrollBBase+($9*64)+(27*2),A1
                Jsr     Word_2GVRAM    
                Lea     ScrollBBase+($b*64)+(27*2),A1
                Jsr     Word_2GVRAM    
                Move.w  #AsciiOffset+CHR_Palette3+CHR_HighPri,D5 ; Set up character color.

@DoneSeperators:
                Move.w  CurrentDistance,D7                      ; Get whole part of DISTANCE.
                Moveq   #3,D6                                   ; Three characters.
                Moveq   #'$',D2                                 ; Lead with a spaces.
                Lea     ScrollBBase+($5*64)+(25*2),A1           ; Screen destination.
                Jsr     PrintVal                                ; Print it.
                Move.w  CurrentDistance+2,D7                    ; Get fractional part of DISTANCE.
                Moveq   #2,D6                                   ; Two digits.
                Move.w  

0xDFEF3:

                                              _No1,VIEW_NOT_FLIPPED,VIEW_SIZE_6
                Dc.b    VIEW_PLANET10,VIEW_PAL_NoA,VIEW_FLIPPED,VIEW_SIZE_6

                Dc.b    VIEW_PLANET4,VIEW_PAL_NoC,VIEW_FLIPPED,VIEW_SIZE_7
                Dc.b    VIEW_PLANET10,VIEW_PAL_No1,VIEW_NOT_FLIPPED,VIEW_SIZE_7