Sonic Adventure/Beta elements

This article pertains to the beta elements from Sonic Adventure and its remake Sonic Adventure DX: Director's Cut.

Title
Sonic Adventure was originally titled Sonic RPG, and was intended be released on the Sega Saturn. However, by the time the Dreamcast came out, the developers moved the project over to that console to test out the new hardware.

Classic characters
Sega originally wanted the Classic forms of the characters in the game, but decided to fully use the Dreamcast's capabilities, and ultimately re-designed Sonic, Tails, Knuckles, Amy and Eggman.

E-Series
E-103 Delta, E-104 Epsilon, E-105 Zeta originally had the same color as E-102 Gamma (except their laser-cannons that are different). This can confirm in the E-102 Gamma tutorial.

Super Sonic
Like in previous games, Super Sonic was originally going to be playable in regular stages. It is possible this was removed for more bug fixes. There is an unused audio file within the game's data in which Tikal explains how to transform into Super Sonic: "Gather 50 rings, and press the Action button while you jump. You'll transform into Super Sonic! But watch out for your Ring consumption."

Emerald Coast
In Sonic the Hedgehog's gameplay, when he is chased by an orca, there are no Dash Panels on the docks.

Windy Valley
Windy Valley was a completely different stage in early development. There are a few screenshots showing Tails flying around in an unknown location and also some gameplay footage showing Sonic and the rest of the cast walking around in this unfamiliar environment. Even the final release's intro video and Amy's very first cutscenes show pictures of this place which was later proven to be a beta version of Windy Valley. Remnants of the stage were found within the files of the Sonic Adventure Auto-demo. Attempts to launch the level within the game itself weren't successful yet because of missing files which cause the game to crash when trying to do so. This geometry seems to be the beta version of the third section of Windy Valley which was partially used as a beta Chao Garden as well. Pre-release footage also shows that the first section had its own beta version as well and was partially recycled for the final design. Amy and Big were originally playable in this stage and there were several blue springs encased in a platform that were deleted from the final version.



Sky Chase Act 2
Originally, Sonic and Tails would have their classic designs from Sonic R like Sky Chase Act 1, and they were supposed to use the Tornado instead of the Tornado 2, so that means that the Tornado 2 doesn't exist in the early version of the game. The Tornado 2 originally didn't transform.

Little purple enemies
Those little purple enemies of Final Egg were originally purple and yellow.

Unused Duck enemy
In the Sonic Adventure Auto-demo, an unused duck enemy was found in Final Egg. While its Al is not completed, the duck has an animal inside it, which will be freed once the duck is hit.

Hot Shelter screenshot
There is a screenshot found among the files on the disc of the Dreamcast version of Sonic Adventure that was going to be used on the official website of Sonic Adventure, but was left unused. This screenshot depicts Big in Hot Shelter.

Unused object layout
Knuckles is usually confined to the room with the light panel puzzle in Lost World. However, by entering Sonic's section through glitches, one can be seen that these areas are filled with objects. This layout appears to be from an earlier version of the stage, as many objects are either in different locations, missing or not supposed to be there.

Gate object
There is an unused object that appears to be a gate in Lost World. It moves up and down and cannot harm the player, but it can push them through the floor. Interestingly, pausing the game will only slow its movement down slightly.

Unused switch
An another unused object in Lost World is a switch. It has a pad for both pushing and toggling and can be walked over normally, unlike other switches which must be jumped over. Its purpose is unknown.

Unused Action Stage layouts
Usually, characters that enter Action Stages they are not intended to be in will use Sonic's Action Stage layout. However, some empty level layouts still exist within the game files, some of which are still a part of the character's different playthroughs. Many of these layouts are outdated and with incorrect objects in them:
 * Sonic has object files for a number of Action Stages he does not appear in, including Hot Shelter and ZERO. He also has files for several unused sections, such as the second section of Hedgehog Hammer, the third section of Emerald Coast and Twinkle Park, and the fourth section of Final Egg and Hot Shelter.
 * The object files used for the test levels (SET0000S and SET0001S) are still present in the game files. While the latter only contains a single Ring and can be accessed, SET0000S is incompatible and will crash the game should the player try to access it.
 * The object file Tails uses for his cutscene with Sonic at Emerald Coast is identical to Sonic's version, except it lacks the Capsule. The entire Action Stage layout is loaded, but only a small part of it is seen.
 * Tails has object files for all sections of the of Sky Deck, including the second and third section. Tails' second and third sections are mostly empty, containing only a small number of obstacles.
 * There is a file for the Mystic Ruins Angel Island area included in Amy's gameplay, but it is never accessed in normal gameplay.

Hidden Rings
In many of the Action Stages in Sonic Adventure, there are Rings floating out of bounds.

Unused sections
There are a number of unused sections in the game. Most of them are empty and have files for objects or textures.
 * Hedgehog Hammer has a single unused section after the one in the final version of the game. This section only holds a single Ring.
 * Hot Shelter has two unused sections after the third section in the final version of the game. They have no geometry or starting coordinates, but they have texture files and they use the music from the second and third section. The fourth section holds one Ring, while the fifth section has no objects at all.

Final Egg leftovers
Final Egg has some interesting leftovers from the earlier stages of development. There are two paths at the beginning and the end of this Action Stage that are cut off from the main level by walls. Furthermore, an unused leftover of the Final Egg from the Autodemo version of this Stage holds a bizarre layout of objects, including Capsules and hazards. It also has a spawn point for Sonic far away from these objects. This section was originally a part of the Final Egg in the demo, but was moved to the Egg Viper's boss area in the final version.

Ice Cap leftovers
Leftovers from other sections exist in Icecap that cannot be seen normally. These include the mountain top from the third section in the first section of Sonic's version of the Action Stage (which Sonic cannot get close to in order to make it appear). Also, a part of Big's path in the small pool can be found in the second section of Sonic's version of Icecap. This path is cut off from Sonic's level by a layer of ice.

Sand Hill
There are two forked sections in the rightmost path of Sand Hill that have one path blocked by large objects.

Unused flags
There are a small number of unused flags in the game for certain characters that will open up areas that they will usually never go to:
 * Amy has a flag for opening the door to Casinopolis.
 * Amy has a flag for opening the entrance to Mystic Ruins Angel Island.
 * Big has a flag that opens the entrance to the Casino District in the Station District.

Uppercut
Knuckles was going to use the uppercut but was then scrapped for unknown reasons. The Uppercut is used in the autodemo version of the game, and like the Punch Attack, it consists of three steps which end with a fully charged, upward punch.

Sky Chase Dragon
There was an unused mechanical twin-headed dragon that was going to be a mini-boss in both acts of Sky Chase. It is invincible, but its programming is very limited as it only follows the Tornado in flight without attacking it. In a prototype image, the Dragon could breath fire. The battle against the monster was called "Sky Attack" in earlier screenshots.

Loading screen
The loading screen was originally in the middle of the screen and had the title of the game in black and white.

Chaos Emeralds
The Chaos Emeralds originally had their design from previous games.

Overall layout
Originally, each area of Station Square was going to be completely connected. Some leftovers of this attempt can still be found within the final release if the player meets certain conditions and activates debug mode: an untextured floorless version of the Casino Area can be accessed from Station Square's coastal area which loads itself as a part of it, suggesting that at some point in development the Station Square hub area was supposed to be loaded in its entirety. Also, more pedestrians were originally planned to roam around the city as evidenced in some screenshots. It is also possible to see the Casino Area by loading it up, leaving it and glitching out of the map.

Hotel layout
There is an early hotel object layout for Big the Cat that can only be seen before completing Icecap. Since Big cannot enter the hotel before completing that Action Stage, this layout is never seen. Two Key Stone are placed on the floor there, which Big is supposed to use to open the doors to the pool area.

The message "なんどこれ？" (when translated to English it says "What is this?") will appear when Big picks up one of the keys. This message will be in Japanese, regardless of the game's language setting.

Chao lobby (used in SA2)
This video is about SADX Prototypes. Seven minutes and twenty seconds into it you can see Omochao and the beta version of the Chao lobby.

Character select
In early character select, the game urges the player to "Choose your Buddy!". The player has to select a character by highlighting their image and pressing the A button.

Loading screen and Chao emotes
A leftover loading screen from the AutoDemo version still exists in the game files which displays various Chao emotion icons.

Unused item bonus
A stopwatch that would have likely frozen the timer and/or enemies appears in the game files.

Vs. Tails
Among the menu graphics for the last completed Action Stage, a "Vs. Tails" setting can be found. As Tails is never fought by any character, it goes unused.

Characters
There are unused characters in the game files that look like Rank icons. These were probably used on the older HUD in the AutoDemo. The demo contains the "Level" part that these letters would have likely been used for.

Lure icon
The icon that was used as Big's life count in the AutoDemo can still be found in the game's files on the final version.

City background
In the game files, there are two versions of the city background seen in Sonic's story intro - one 256x256 version and one 512x512 version. Only the 256x256 version is shown in the game.

Tornado Health Bar
The red "Tornado" life gauge is used in both acts of Sky Chase, despite the fact that Act 2 uses the Tornado 2. As such, the blue "Tornado2" life gauge is never used.

Spring Model
A spring model which resembles the spring from Sonic Jam is seen in the game files. The model is most likely a placeholder, as the texture does not fit it correctly and may have served until the final model was finished.

Star Panel
In the Autodemo version of Sonic Adventure, there was star panel that was used to mark the spot the player would land on after using the Jump Panels. This is not used in the final game.

How to play and Gliding tutorial
"How to Play" and the Knuckles's Gliding tutorial pictures from the Tokyo Games Show demo version of the game can be found in the game files:

Early Japanese trailer lines
Voice clips that were used in various early Japanese trailers can be found in the game files for both the English and Japanese version of the game:

Tikal's lines
There is a variety of unused lines for Tikal left on the game disc, including for the "Super Sonic" storyline and the Chao Garden:

Chao Garden
Clips of Tikal explaining how the Chao Garden works. In the final game, Hint Boxes explain how they work instead.

Idle lines
The characters say one of two lines relating to their surroundings if they stand idly for an extended period of time. Each character usually has one generic line and one unique to the stage they are currently in. However, many of these lines are impossible or otherwise extremely difficult to trigger in-game, such as during boss fights.

Main themes lines
There are menu lines said by all the characters (including Eggman and Tikal) for the "SEGA", "Sonic Team", "Adventure Mode" and "Trial Modes" options. In the final game however, both the SEGA and Sonic Team logos do not play sounds and both Adventure Mode and Trial Mode only uses the voices from the characters on the Character Select menu.

Unused Text
The line "Now, you can play with SONIC!" is seen in game files, but it is unused in all versions of the game because Sonic is unlocked from the beginning.

Unused cutscenes
An unused cutscene from E-102 Gamma's story can be found in the game files, which is implied to have been played should the play fail Final Egg. This cutscene includes Eggman speaking the following lines: The Japanese variant of the cutscene has some differences in comparison to the English one: Additionally, an alternate version of the cutscene featuring the Tornado 2's transformation can be found among the voice clips for Sonic's story. The clips used in-game can be found among the lines for Tails' story, so these were probably intended to be used for Sonic's story, but were not used in the final version:
 * What is this!?
 * I'm so disappointed, you useless machine!
 * All right, then. Back to practice! Go on, get going!
 * What's wrong, Gamma?
 * You can't even clear a training room?
 * Ugh, never mind! One more time! Go on, get going!

Emerald Coast elements
Through certain glitches, other characters can access Sonic's segment of Emerald Coast. Completing the first part of the stage dumps the character into a void outside the playable level where a single Spring can be seen. This is actually the default starting point for characters other than Sonic, but the purpose of the Spring is unknown. With a well-timed Spin Dash, it is possible to jump so far that the Spring can be seen.

There are also many leftovers from Sonic's Emerald Coast in Big's version, ranging from Dash Panels to Rings, to Springs. The objects in Big's Action Stage seem to be from an older version of Sonic's Action Stage. This include a lone Dash Panel where the first loop would be, instead of multiple panels. These objects also appear in the AutoDemo.

Casinopolis elements
Right at the start of the "Dilapidated Way" in Casinopolis, there is a passage up to the right. Although it is clearly visible, it is out of the way and cannot be accessed by Sonic or Tails,due to an invisible wall. It goes on for some time, twisting and turning, but abruptly hits a dead end. Its purpose is unknown though it resembles the other tunnels found in the same area.

The items found on the path differ between Sonic and Tails: As Sonic, the path is empty, except for two Item Boxes (containing an Extra Life and High-Speed Shoes) at the top of the path. As Tails, the path contains a Thunder Shield and several trails of Rings.

Mystic Ruins elements
Underneath the ground near the waterfall in Mystic Ruins, there is a row of fifteen blocks which are normally never seen.

Triangle
In the area where the player meets Tikal in the past, there is a triangle hidden inside the Shrine of Knuckles's race.

Unseen Ads
In the second section of Station Square, there are two ads which are positioned outside of the boundaries of the Adventure Field.

Sonic's pose
There is an unused pose that can make Sonic turn his head. On the character select, he will face his left, but during gameplay he will try to look towards the camera. This is cannot be done on the Dreamcast's controller since it does not have the required buttons to recover it. This is only possible with other types of Joysticks.

Duplicate clock
The clock at the top of Station Square's City Hall has another clock behind it that cannot be seen normally. The purpose of this extra clock is unknown.

Chao Card
In Sonic Adventure DX: Director's Cut, there is an unused item from the "Chao Stadium" that would let the player enter the Chao Race. This object does not have an English translation when grabbed, instead presenting Japanese texts saying "Chaocard Proof of Chao Stadium membership".

Duplicate Lure
There is an extra Lure that can be found in the area where Tails obtains the Jet Anklet. However, Big is unable to reach this area normally. This extra Level Up Item is a copy of the one located in the sewer nearby. Collecting either one will cause the other to disappear.

Speed Highway elements
In Speed Highway, there is a swing floating in mid-air near Tails' section. The swing only exists while playing as Sonic in Tails' version of the Action Stage.

An unused trash can object can also be found on the list of objects for Speed Highway. This object behaves like other minor, yet breakable background objects in Speed Highway. However, it does not have the correct textures and its lid is slightly misplaced.

Final Egg and Hot Shelter's elements
On the Dreamcast version of the game, there is a Capsule sitting out of bounds near the beginning of Sonic's version of Final Egg which can be reached with a well-timed Spin Dash-enhanced jump, meaning the Action Stage can be completed in less than ten seconds. Aside from that, there is also a piece of level geometry out of bounds in the Final Egg's second act. This piece is impossible to see due to the background and fog. While playing as either E-102 Gamma or Amy, there is also some leftovers from Sonic's version on the first and third sections of their respective version.

In Hot Shelter, there is a 1-Up above the player in the large room where Amy must press a switch to release water. The path to it is blocked, making it impossible to obtain. In addition, there are some leftover areas from Big's version of Hot Shelter outside Amy's version of this Action Stage. Those leftovers contain Rings and various Item Boxes.

Casinopolis signs
There are two unused variants of the giant Sonic and NiGHTS signs seen on the walls near the slots in the main area. The "Emerald Line" and "Galaxy Rose" images displayed on the signs are the same ones that can be seen on various machines around the stage.

Twinkle Park elements
There are numerous leftovers from Sonic's version of Twinkle Park present in Amy and Big's version of this Action Stage. However, they cannot be seen normally since the areas of the leftovers are blocked off.

Windy Valley elements
In Windy Valley, there is an unused tumbleweed object. The object moves in a fixed cycle and cannot be interacted with by the player.

The gate to Angel Island
The gate that stands between the Windy Cave in the Mystic Ruins Station Area and the outdoor area in Mystic Ruins Angel Island is usually only seen from inside the cave. If the player somehow gets outside the cave while the door is closed, they can see that the other side of it has its own unseen, unique design. The gate also has an opening and closing animation that is never seen either.

Falling tree
When the player explores Mystic Ruins in the past near the Altar of the Emeralds, there exists an unused tree object that splits in half when approached (if that tree is reactivated in the game files). It will appear on the middle of the path to the altar.

Red Mountain elements
Some objects from Sonic's version of the second section of Red Mountain exist in E-102 Gamma's version of the action stage. They cannot be seen because Gamma never gets to this part of the action stage.

Perfect Chaos
There is unused attack used by Perfect Chaos in the game files where Perfect Chaos forms a small arm from the floods to attack Super Sonic with. However, the attack is not fully finished.

Realistic blue hedgehog
A painting of a realistic blue hedgehog can be found inside the game files. This picture can also be found in the gallery Sonic and the Secret Rings. Its purposes are unknown, although it was featured in the game's 1998 behind the scenes segment at the Tokyo International Forum.

Unused music
There are a number of tracks in the Jingles section of the game's Sound Test that are not used in the final version of the game:
 * A jingle that would play if Big loses a fish.
 * A jingle listed as 'Extend' in the Sound Test. Previous Sonic games played a fanfare upon obtaining an extra life (called an "extend" in Japanese gaming jargon), so it was presumably meant for that purpose. However, the final game uses the "Chaos Emerald" jingle from earlier games for this purpose instead.
 * An unused theme for Station Square, and two for Mystic Ruins. They would likely have been played during the loading screens for the adventure fields.

Other jingles
There are tracks in the "Jingle" section of the Sound Test labelled "JINGLE A" to "JINGLE E". They seem to have been used for the Sonic Adventure  Homepage, but were not used in the game itself.

Japanese level list
In each version of the game, there is a Japanese level list that contains three empty level slots listed as "きのこ" (Kinoko), "ジャングル" (Janguru), and 砂漠 (Sabaku). In gameplay, there is not a particular Mushroom or Jungle-themed level, though the "Desert" might be a placeholder name for Sand Hill.

Starting point
There are many Action Stages in the game that include starting point for characters that do not normally go to that specific stage or act:
 * Sonic has a starting point to go in Big's Act of Emerald Coast.
 * Gamma has two starting points to go into the second and third sections of Windy Valley which are unused. These are actually the starting coordinates that were used for Sonic in the early version of the stage.
 * Tails starts next to the Capsule at the end of Sonic's Red Mountain. However, the game will force the player to leave the level immediately afterward.
 * Tails and Knuckles have different starting points in areas out of bounds of Sky Deck.
 * In Lost World, Knuckles has a starting point below where Sonic does.
 * In Casinopolis, every character has the same starting points as Sonic in all Acts.
 * In Final Egg, Gamma starts at the same location Sonic does in the AutoDemo. Amy and Gamma have different starting points for this stage too. Though Sonic, Amy and Gamma also have starting points for the unused fourth section of the action stage.

Miscellaneous

 * Tails has a small number of actions in the game that he never uses, either as a playable character or while following Sonic:
 * Tails has a working "Pinball mode" for the pinball tables in Casinopolis. However, much like Sonic in the Japanese version of the game, Tails cannot shake the table.
 * Jump Panels are functional for Tails, whereas Knuckles and Amy will get stuck on the second panel they use, and Big/Gamma cannot use them at all.
 * Upon entering the menu, the following string is loaded into the RAM: "Team Andromeda".
 * Pressing or  as Sonic or Tails while riding a snowboard causes them to duck. Ducking has no effect on Sonic or Tails and lasts for as long as they stay on the ground, or until they land on the ground from a fall.
 * Similarly, holding down on the analog stick as Sonic will cause him to stand sideways on the board. This seems to be part of a braking mechanic, as Sonic demonstrates attempts to slow down.

Autodemo
The AutoDemo is a build of Sonic Adventure designed to showcase the game through CPU-controlled demos in certain Action Stages in the game. With a burn date of October 16, 1998, this build predates the Japanese final release of the game by approximately two months.

Music
The are twenty-nine music tracks present in the game's build, some of which have noticeable differences from their final versions.

Knuckles
In Knuckles' version of Red Mountain, there are texture packs of ghosts. The game files also reveal that Knuckles was supposed to have tutorial textures.

Test levels
In the game files, there can be found three models of test levels for Sonic Adventure.

Station Square
By extracting the Station Square geometry, it is possible to see some differences relating to the field's earlier design:
 * The Twinkle Park entrance is completely different.
 * The hotel has a sign.
 * The dock which leads the player to the Egg Carrier does not exist. This may suggest that the player originally would not be able to go back to the Egg Carrier after completing the game.
 * In the Hotel area, the ladder shown in some of the prototype pictures still exists. The pool area also has different placements of the chairs and tables.
 * The sewer area where Big obtains a lure has a much lower ceiling.
 * The slope between the street and the beach is smaller.
 * The Skyscraper is much taller than in the final version of the game.
 * The Station District has no entrance.
 * The player cannot ascend the stairs in the Station District properly.
 * The player can walk along the train tracks.
 * The front of the Hotel District has no collision.
 * The billboard of the Casino does not advertise Chao in Space. In its place, there is an advertisement for "The Man 3", though only the top-left of it is shown.
 * There is a poster above an awning in the alley of the Casino District that is not in the final version of the game.
 * In the Hotel District, the player does not have a spawn point.
 * In the Hotel District, there is a chandelier that does not appear in the final version of the game.
 * There is a ladder shown in the prototype images that still exists in this version.
 * The pool area from the Hotel District has different placement of the chairs and tables in this version.
 * The tables and sunbeds by the pool are arranged differently than the final version of the game.
 * The only difference in the City Hall District is that one door on a building next to the sewer in the City Hall appears to be reflective (glass) instead of using a texture like the final version of the game.
 * The water is present, but is invisible due to the incomplete map of this version.
 * The player will spawn out of bounds in the Twinkle Park District in this version.

Mystic Ruins
The Mystic Ruins crashes upon trying to access it. By extracting the geometry some minor changes can be seen.
 * The Eastern Cave with the imprisoned Kiki is in a slightly different shape compared to the final version of the game.
 * The Ancient Light ledge in the Mystic Ruins Angel Island section is missing in this version.
 * The bridge on Angel Island is slightly different compared to the final version of the game.

Egg Carrier
The Egg Carrier has some notable changes to its adventure field in the form of object layouts:

Front deck

 * There are Item Boxes below the Captain's room containing Random Rings Item Boxes in this version.
 * There is no Spring at the back of the Center Dome where Chaos 6 is fought in this version.
 * There are many circles and lines of Rings present around the deck in this version.
 * The Monorail is missing in this version.
 * The Springs in the landing area point straight up instead of being set in an angle in this version.
 * There are no Hint Boxes at the Center Dome where Chaos 6 is fought in this version.
 * The Center Dome for the Chaos 6 battle sticks out, unlike in the final version of the game where it is flat. The low-detail version viewed from the back of the ship when transformed actually makes it into the final version of the game, but it is difficult to see.
 * The Item Boxes around the Center Dome are in different locations and contain items that include two High-Speed Shoes, an Extra Life and a Super Ring.

Rear deck

 * Behind the swimming pool building is two Random Rings Item Boxes and an Extra Life. In the final version of the game, this was changed to two Super Rings.
 * There is a cannon on the middle platform of the large tower that is not there in the final version of the game.
 * The large, spinning platform at the top of the tower does not appear in this version, nor does the Super Ring slightly below it.

Main hall

 * The monorail is missing in this version.
 * The lighting is slightly less greener than in the final version of the game.
 * The doors have a very bright lightening in this version.
 * There are five maids in the bottom area. In the final version of the game, there are three maids.
 * There is no puzzle outside the Chao Garden Portal in this version.
 * There are Rings and two Super Rings at the back of the room that were removed in the final version of the game.
 * There are no Hint Boxes in this version.
 * The robots moving along the left and right side of the upper area are missing in this version.
 * The pods, elevator and arches going over the room are not solid in this version.

Prison

 * The lightening is different compared to the final version of the game. There is also no fog in this version.
 * This version loads textures and objects due to Knuckles' cutscene taking place here, though instead of playing the Knuckles fight scene for the third demo, it plays Amy's cutscene with Gamma instead.
 * The middle cell contains a Random Ring Item Box and an Extra Life. In the final version of the game, these were replaced with the a black Chao Egg.
 * The cells make no sounds when opened in this version.
 * There is no Lure in the rightmost cell for Big in this version.
 * The fans below the floor spin slightly slower in this version.

Misc

 * There are no Item Boxes on the upper levels in the Pool room.
 * Sonic's cutscene will load if the player tries to enter any map from the Egg Carrier's exterior.
 * The entrance to the Private Room is on the right side of the room, rather than the left.

Windy Valley
The geometry and level design for the prototype version of Windy Valley seen at the game's official Japanese unveiling are partially intact. The proper textures are missing, however, and thus the model substitutes its textures for those of Red Mountain in the screenshots. This version of Windy Valley is very large open-ended in comparison to its more linear counterpart from the final game. While the geometry for Act 1 seems to follow the same rough path as the final version, the third section is entirely different. All three parts have their original texture listings and start positions present in the game's coding, although the level file itself only contains Parts 1 and 3, skipping the tornado section. While the mesh for Part 2 does exist, it does not have the necessary entries in the level file itself.

Speed Highway
Speed Highway was used for Sonic's Autodemo and the only Action Stage for Sonic that can be completed normally. Tails' version of this Action Stage is pretty much identical to Sonic's, but he is not able to move correctly. In all the sections of Sonic's version of Speed Highway, the Hanging Bell is silver, unlike in the final version of the game.


 * The starting point is very different. The ceiling is lower, and the walls use a different texture.
 * The camera at the starting point is lowered in this version.
 * A 1-Up on the platform to the right of the starting point was changed to a Thunder Shield in the final version of the game.
 * Three Rings at the top of the two large buildings at the beginning of the Action Stage are changed to a 1-Up in the final version of the game.
 * In the middle of the buildings at the beginning are Item Boxes containing a 1-Up, Random Rings and another 1-Up. In the final version of the game, this was changed to five Rings, a 1-Up and another five Rings.
 * The building before the first checkpoint is very different from how it looked in the final version of the game. It has Hint Orbs, Rings and more décor in this version.
 * There are no Rings to collect in the moving platform section.
 * There is no Invincibility or High-Speed Shoes on the wall Sonic runs along.
 * To the right of the checkered area of the lower path, there is an empty building. In the final version of the game, it has Rings, a Cop Speeder and a 1-Up.
 * The small slope just before the building with the bell area on the lower path has six Rings instead of eight in this version.
 * Sonic is slower than normal when going up the stairs near the bell in this version.
 * There are two Super Rings below the bell area. In the final version of the game, one of these is changed to a Shield.
 * Rings were added after the Dash Panels after the bell in the final version of the game, unlike here.
 * Two lines of two Rings were turned into one line of four Rings in the final version of the game just before the tunnel.
 * There are two Rings at the end of the tunnel in the lower path not present in the final version of the game.
 * Double line of Rings before the square moving platforms was reduced from six to four in the final version of the game.
 * There is no High-Speed Shoes on the upper path to the square platforms.
 * The camera on a 1-Up under the first square platforms part is slightly different in the final version of the game.
 * There are arrow signs next to the three Springs that launch the player over to the Helicopter.
 * The Hint Orb near the Helicopter does not have Rings surrounding it in this version.
 * When Sonic hits the Spring that takes him to the Helicopter, he is facing the camera (with his back turned to the helicopter) while in the air. In the final version of the game, he is facing the helicopter, with his back turned to the camera.
 * The High-Speed Shoes in the area after the Helicopter is missing in this version.
 * There are two 1-Ups after the upper path's Homing Attack chain above the end of the section. In the final version of the game, the 1-Ups were reduced to one.
 * A circle of Rings was added to the bottom of the large circular building in the middle path in this version.
 * A line of four Rings on the slope leaving the circular building in the middle path is square in this version.
 * A line of six Rings at the Dash Panels after the moving platform is reduced to four in this version.
 * The large building on the lower path only has two squares of four Rings, three Cop Speeders, and a Super Ring surrounded by a semi-circle of rings. In the final version of the game, the building adds two more squares of rings, three 5 ring boxes, two Spiky Spinner and changes the 10 Ring Item Box into a Shield surrounded by a square of Rings.
 * The second moving platform has no Rings.
 * A line of four Rings at the end of the middle path (where it meets with the lower path) is missing in this version.
 * Two lines of three Rings on the road approaching the area with the rocket were changed to three straight lines of four Rings in this version.
 * The Bladed Spinner and the Explosion Item Box are absent at the rocket area in the in this version.
 * A line of two Rings next to the rocket were changed into a line of four Rings in the final version of the game.
 * One of the buildings in Tails' section of the map has a chunk of geometry missing in this version.
 * The text for the Hint Orb's messages in this Action Stage are as follows:

Section 2

 * When Sonic pushes on the barriers in Speed Highway, a sound effect is played that sounds like something scraping along the floor. This does not occur in the final version of the game.
 * The bottom of the Action Stage is completely different. There are no benches or posters, and more palm trees than in the final version of the game. This is also where the Action Stage, with a capsule being present and the path to the third section is blocked off. The transition to the third section still exists, but the textures will be incorrect if the Action Stage is accessed this way.
 * There are no objects or lights in the small starting area.
 * The controls moving left and right while running down the building are slightly looser than the final version of the game.
 * There are no Item Boxes in this version of the section.
 * The circles of Rings at the end of the section are missing in this version.
 * There are a more plants on the ledges above the bottom of the Action Stage than in the final version of the game.

Section 3

 * The lighting is very different compared to the final version of the game. It is noticeably more blue, similar to the first two sections of this Action Stage. The lighting in this section also appears to shine on Sonic differently.
 * The Action Stage is textured very differently compared to the final version of the game. For example, many platforms use brick textures rather than what they use in the final version of the game.
 * There are major changes to the buildings in this part of the Action Stage, most notably around the center of the map.
 * The camera at the start of the section for Sonic is different.
 * The start of the section is noticeably different. There are Rings on the small walls that are not there in the final version of the game, the road is slightly wider, there is a continuous line of ten Rings at the Dash Panel near the start, and a checkpoint that is not present in the final version of the game.
 * There are more decorations on the sidewalk, including plants and newspaper stands in this version.
 * There is an area with a High-Speed Shoes to the right of the Dash Panel near the start that was replaced with a building in the final version of the game.
 * There is a hole in the road with a clock tower, benches and Rings inside near the start that is not present in the final version of the game. This is the same clock tower hole that can be seen in early images of the game.
 * The Bladed Spinners located at the clock tower hole in the final version of the game are missing.
 * On the building to the left of the hole are awnings and a platform with a Ring on it that are not there in the final version of the game.
 * There is a searchlight at the top of the building to the left of the start of the Action Stage that is not in the final of the game.
 * The High-Speed Shoes on the building to the left of the start is in a different spot, and neither has Rings surrounding it or the containers near it from the final version of the game.
 * There is a Jump Panel on the High-Speed Shoes building that is not there in the final version of the game. This Jump Panel sends the player quite far.
 * The path leading the main street is wider than in the final version of the game. There are also four Bladed Spinners before the glass roof that were reduced to one in the final version of the game, and there are many more plants at the area on top of the glass roof than there are in the final version of the game.
 * Due to the path from the previous point being wider, there are twelve glass panels instead of nine in the roof in this version.
 * The entrance to the small tunnel Sonic can run through lacks a Shield Item Box and the ledge is narrower and not directly connected to the tunnel.
 * A set of two Rings on the ledge to the right of the panels were changed to a set of three in the final version of the game.
 * There is a line of Rings missing on the wall Sonic runs across in this version.
 * The building that Sonic can run on top of has a steeper roof with two Bladed Spinners on it. In the final version of the game, the roof is slightly lower and the enemies are replaced with containers, Rings and a five Super Rings. There are also arrow signs on top of the building that are replaced with four posters in the final version of the game and an overhead camera that is not present in the final version of the game.
 * A line of three Rings is missing from the area the player can access by jumping over to the right of the building's roof in this version.
 * In the small area the player can jump across to, the 1-Up Item Box is in a different spot and the ledge is much larger than in the final version of the game. There is also a Spring here that the player can use the jump onto the building in front of them as a shortcut to the end. In the final version of the game, this is replaced with a small passage with a wall between it and the 1-Up box.
 * The clock at the loop in the road has a different base compared to the final version of the game.
 * There are two Cop Speeders near the clock that are not present in the final version of the game.
 * The sidewalk is lined with Rings, Dash Panels and Springs both on the sidewalk and on small ledges attached to the sides of the buildings. In the final version of the game, there is only one line of Springs that remains and are accessed by skipping across a Bladed Spinner floating over the road (that does not exist in the AutoDemo). These Springs send the player into a small tunnel.
 * The section goes downhill, while in the final version of the game, it goes uphill.
 * The two buildings that the cars drive under are much shorter and able to be walked on top of in this version.
 * The path where Sonic runs along a wall after the first tunnel is different, featuring things such as glass panels in this version.
 * There is a second tunnel that is not present in the final version of the game.
 * The last tunnel is in the form of a Ramp and has arrow signs and a High-Speed Shoes on top of it.
 * There is a long, raised platform that does not appear near the end of the Action Stage in the final version of the game. It has two lines of Rings, a Super Ring, a Spiky Spinner and the fountain that sends the player to the Capsule, with a support column in the place of the fountain's final location.
 * The buildings in the center of the road area are very different compared to the final version of the game. They only have two containers on them and the building heights are very different. The small tunnel with steps in from the final version of the game is also missing in this version.
 * The Cop Speeders near the end of the Action Stage are in different locations compared to the final version of the game.
 * The Spring to enter the small tunnel in the building near the fountain does not launch sonic high enough in this version.
 * There are four extra Rings in the fountain in this version.
 * There are a ton of Rings around the city hall building that were considerably reduced in the final version of the game.
 * There are three Springs to the left of city hall and one Spring to the right of it. In the final version of the game, there is one Spring on the left and two Springs on the right.
 * There are Dash Panels in front of city hall that lead to the Spring to the right of the building. The 1-Up there is also missing in this version.

Knuckles
Knuckles' version has an outdated object file, meaning none of the objects that appear in the Action Stage are correct. He can still find the Emerald Shards, but the third shard will sometimes not appear, making the Action Stage impossible to complete. Also, the trash can object that goes unused in the final version of the game are correctly textured here, unlike in the final version of the game.

Red Mountain

 * There is a couple of areas in E-102 Gamma's version of Red Mountain that do not look similar to the final version. The enemies' locations also greatly differs.
 * There is no lighting in the first section.
 * The background drastically differs from the final version. In the final version of the game, the horizon is obscured by rocky walls, but in the autodemo version, forests and distant mountains are visible in the background. The bridge in the Action Stage was also originally red.
 * In the autodemo of Sonic's version of the Action Stage, the elimination inside the Red Hot Skull section was a lot harsher, lava pools were present and the lightning made Sonic look pitch black.
 * In the final version, Red Hot Skull section has very different floor textures, almost light brown. In the autodemo version however, they are dark with black splotches.
 * The Bumper design of the Switch is green button in the Autodemo.
 * The launching platform of the rocket is very different in the autodemo, being a lot bigger than in the final version.
 * There are black areas under Red Mountain in the Autodemo. However, they are filled with clouds in the final version.
 * The transition to Sonic's second section covers a much larger area. Sonic will go to the section as soon as the second zipline ends, instead of when he jumps into the hole nearby in the final version of the game.
 * If the player enters the second section from the first one, the lighting will still be absent. To get the lighting to show up, the player either needs to enter from the level select menu directly or reload the Action Stage by dying/restarting.
 * various Item Boxes and Ring lines in this version have been either altered, replaced, or even removed in the final version of the game.
 * There is a set of crates humorously breathing fire in the second section of this Action Stage. In the final version of the game, it has been replaced with a falling spiked ball.
 * Sonic's Homing Attack is not working very well in this Action Stage, as his movements are kind of circular due to bending downwards. In the final version of the game, Sonic dashes directly into enemies.
 * In E-102 Gamma's version of Red Mountain, Gamma can lock onto enemies, but no numbers are popping up next to them.
 * Some sections lack some enemies.
 * Sonic gives the camera a grim look with an animation not shown in the final game.
 * Some of Knuckles' sections are greatly modified, if not deleted.
 * There is Hint Orb after the small tunnel before E-104 Epsilon.
 * E-104 Epsilon does not react when hit.
 * E-104 Epsilon does not turn into an Animal when defeated.
 * The E-series boss music does not play during E-104 Epsilon's fight.
 * Tikal's hints for Gamma's section read:

Knuckles
Knuckles version of this Action Stage seems to be using the version of the Action Stage from the TGS build of the game. The tutorial for Knuckles is present and there are many more Hint Orbs present than in the final version of the game. The Emerald Shards are always in the same places; in front of the starting point, in the underground at the area Sonic lands at after using the Jump Panels and near the falling spiked ball in the area just after Sonic's first Zip Line.
 * Knuckles' starting area only has three Rings. In the final version of the game, there are six Rings and a Hint Orb.
 * There is a floating line of four Rings in front of Knuckles' starting point. In the final version of the game, there is a Super Ring Item Box.
 * The Hint Orbs are present near the Emerald Shard at the starting point. One is next to the shard, one is on the bridge and the other is on the other side of it. The third one was moved to Speed Highway in the final version of the game.
 * A line of Rings on the path to the rocket at the bottom of the mountain are missing in the final version of the game.
 * The switch puzzle for the rocket from Sonic's version of this Action Stage is used in Knuckles' version too. In the final version of the game, Knuckles' rocket is already activated and the switch has been replaced with a square of four Rings.
 * Knuckles' restart position is at the same place as the first Emerald Shard. The final version of the game uses his original starting point.
 * A Super Ring and an Invincibility are missing on the side of the mountain below the area with the rocket.
 * At the top of the mountain are three Hint Orbs. In the final version of the game, one was removed while the two other are placed in different locations.
 * The Zip Line platform is empty. In the final version of the game, there is a Kiki and a circle of Rings.
 * At the line of Bladed Spinners near the starting point, there is a Hint Orb that is absent in the final version of the game.
 * The line of four Bladed Spinners was replaced by a line of three in the final version of the game.
 * A Super Ring on the opposite side of the leaning platforms is missing.
 * Underneath the collapsing platform after the first Zip Line section is an extra fire-breathing skull.
 * Another Hint Orb after the collapsing platforms near the Jump Panel section. This one (where Tikal talks about buried Emeralds) was moved to the starting point in the final version of the game.
 * A Bladed Spinner was moved from over a pit to near the collapsing platform area in the final version of the game. The number of them was also reduced from three Bladed Spinners to just one.
 * A Kiki was replaced with a Gola nearby.
 * On the top of a mountain behind the starting position is another extra Hint Orb in this version.
 * To the right of the starting point is a small, but tall mountain. On top of it are two spiked balls and a Hint Orb. In the final version of the game, there are three spiked balls in a triangular formation and a Super Ring nearby.
 * Tikal's hints read:

Emerald Coast
Emerald Coast differs from its version in the final game in a number of ways and is rather incomplete. The lighting is very dull compared to the final game, many objects, including rails and chairs, are missing, and the Action Stage lacks death planes. There is no music in the first two sections, nor do any section transitions exist.

Section 1

 * Sonic starts directly above his starting point in the final version of the game. When he lands, the camera angle is different.
 * There are no Item Boxes behind the starting point in the Autdemo.
 * Ihere are two Rhinotanks near the bridge instead of one.
 * Only four springs under the bridge at the beginning of the Action Stage exist instead of five. Some are also floating without supports.
 * There are no rope barriers on the platforms after the Springs, or swinging spiked ball in the middle of the area after the Springs. There is also only one Spring for getting Sonic back up to the bridge before the loop.
 * The first Shuttle Loop only has one Dash Panel. It also has a very different camera angle than the one in the final version of the game.
 * There are extra Rhinotanks before the Ramp.
 * There are no Item Boxes around the back of the island with the Ramp.
 * There is a Kiki instead of a checkpoint after the jump ramp.
 * There are extra Dash Panels in the small area Sonic runs through after the jump ramp.
 * The checkpoint before the Orca chase section is placed right after the second loop, rather than just before the chase itself.
 * The Orca and its chase section is completely missing.
 * There is no Kiki in a tree next to the second spike wall.
 * Three Random Ring Item Boxes from the final version of the game are missing from behind the large island near the lighthouse.
 * There is an extra Spring added while climbing the large island.
 * There are fewer floating islands around the 1-Up Item box near the end of the section than in the final version of the game.
 * The player will not get picked up by wind if they fall down one of the holes around the lighthouse.
 * There are Kikis on the rails near the lighthouse, unlike in the final version of the game.
 * There is no Kiki above the section transition point.

Section 2
Section 2 is missing most of the objects that appear in the final version of the game. Notably, the latter parts of the Action Stage are almost completely empty:
 * There is an extra set of Rings after the first checkpoint that does not appear in the final version of the game.
 * The last two checkpoints are missing.
 * The Ring layout on the wall near the start is very different. Only small single lines lower down. There is also no Power Sneakers on this wall either.
 * There are no objects in the higher tunnel accessed from the wall.
 * Springs at the upper path do not work correctly consistently and follow a different path.
 * No 1-Up Item Box or Dash Panel after the Springs in the upper path.
 * The Sweepers are at the bottom of the pool rather than on the surface. There are also three of them, with the final version of the game reducing them to two. There are also no Air Bubbles or platforms in the water.
 * There is no circle of Rings after the pool.
 * No Super Ring in the spike wall area.
 * There is a Super Ring after the spike walls that has been replaced by a Kiki in the final version of the game.
 * There are very few Rings before the big loop.
 * There is no Dash panel after the big loop.
 * The Ramp encountered afterward does not work correctly.
 * The area with the large steps in the final of the stage lacks the objects.
 * There is a Kiki on a small tree in the large step area that is not there in the final version of the game.
 * The Item Boxes, Kikis and Hint Orbs are missing in this area.
 * The alternative route to the Jump Panels (Spring) does not work. The Spring sends the player to a bottomless pit.
 * There are only four Jump Panels there.
 * The last Jump Panel is slightly to the right of the platform the player is going to, rather than directly above it. There are also no spike walls present.
 * The end island is completely empty, unlike in the final version of the game, where Tails/Capsule (depending on the mission) can be found here.

Big

 * Big spawns on the island in the secret cave area, rather than on his usual starting point on the beach in the final version of the game.
 * There is a light effect over the island that is not in the final version of the game.
 * There are no fish. The only thing available to catch is Froggy.
 * The exit to the cave has been blocked off.
 * The game will crash if Big goes up the slope where Sonic's first Spring/extra life Item Box is in the final version of the game.
 * A 1-Up from Sonic's version of this Action Stage is still present.
 * Objects from Sonic's version of this Action Stage (the objects before the loop) still exist and seem to be from later along than Sonic's sections. The rope rails exist and there is a lot more décor, like the previously-missing Springs.
 * Froggy is very weak and it is impossible to break Big's lure even if his reel gauge reaches its limit.

Casinopolis
The most notable feature of the early model for the first section of Casinopolis is the "Bunny girl" that would ultimately become the Cowgirl in the Japanese release. The bunny girl is 3D unlike the Cowgirl, who only appears on a billboard. The model of a bar that does not exist in the final can also be seen nearby.

The second section has an early design for the long path that goes unused in the final version of the game. The third section (Sonic Pinball) is virtually the same as in the final version, but (NiGHTS Pinball) is very different to the final version of the game; it forms a long, curved shape that looks nothing like the table used in the final version, but much like the prototype images released early by Sega for the stage.

Section 1

 * The start of the Action Stage is missing a Hint Orb and an Ice Ball.
 * The small tunnel at the start only has one Dash Panel and it is placed at the end rather than two at the beginning of it and a line of Rings.
 * The Dash Panel sends Sonic into a Spring that does not exist in the final version of the game.
 * The area at the bottom of the hill is completely empty other than the icicles preventing Sonic from going further. The Jump Panel area and the Dash Panels are also missing.
 * A Dash Panel near the entrance to the cave that sends Sonic into the Spring to bounce him up there was replaced by a line of seven Rings in the final version of the game.
 * There are three enemies present on the hill that are not seen in the final version of the game. These include an Ice Ball and two Boa Boas.
 * The Item Boxes at the top of the hill are missing.
 * Immediately upon entering the snowy cave, the player encounters a line of four Rings that are not found in the final version of the game.
 * To the left of the cave entrance is a circle of Rings that is not in the final version of the game.
 * There are a lot of wooden textures. In the final version of the game, these were replaced with standard walls.
 * There is a curved line of four Rings across a small hole to the next platform here. In the final version of the game, there is a Hint Orb, a Spring and a platform covering up the hole.
 * There is a Spring to send Sonic into the hanging Icicles. This was replaced with a small platform in the final version of the game.
 * There are ten Icicles here. In the final version of the game, two at the right end were removed and a platform was added below to compensate.
 * Taking the middle path at the Icicles sends Sonic into a small platform. In the final version of the game, the platform was enlarged with platforms.
 * Jumping on top of the Icicle area are five Rings that are not in the final version of the game.
 * Taking the right path at the Icicles sends the player to a platform with five Rings, a Random Ring Item Box and a Spring over a small hole. In the final version of the game, there are four Rings, fences and the hole near the Spring has been covered entirely. There are also boxes next to the Spring not present in the final version of the game.
 * To the right of the Spring mentioned above, are three tiny platforms. In the final version of the game, boxes were added and the small platforms were reduced to one.
 * There is an area after the platforms with a Super Ring and a 1-Up. In the final of the game, the Super Ring is removed and the 1-Up is moved to its former location.
 * The entrance to the second section is not solid.
 * The rocket platform is missing. Instead, there is a bridge in its place. There is also an extra Point Marker at the end of the bridge that in the final version of the game, was moved to the beginning of the second section instead.

Section 2

 * There is no rock behind the player at the start.
 * There is a single Spring floating out of bounds where Big's part of the Action Stage would be located.
 * There are boxes when the player leaves the cave. In the final version of the game, this was replaced with a Point Marker, fences and Rings.
 * There are two Ice Balls at the bottom of the cavern. In the final version of the game, they have been replaced by a Boa Boa.
 * The Spring at the bottom of the cavern had five Rings added to its path in the final version of the game.
 * Between the first and second Spring, there is a slightly misaligned line of five Rings. In the final version of the game, this was replaced with a line of four Rings and two spikes.
 * The area below the first Icicles section is empty aside from a Spring sending the player back to the beginning of the area. In the final version of the game, many spikes were added as well as a Spring allowing the player to skip the icicles.
 * The first Icicle section has five Icicles. In the final version of the game, two more were added and the Icicles are closer together. The spikes near these Icicles in the final version of the game are also missing.
 * The spikes near the line of Rings after the Icicles are missing.
 * There is a small hole that the player must jump over with a curved line of five Rings. In the final version of the game, a Spring was added, the line of Rings was reduced to four and a small platform was added over the hole to prevent the player from falling.
 * There is a switch that does nothing next to the small icy pool area. There is also a small line of three Rings floating nearby. In the final version of the game, this was changed into an arrow of Rings.
 * Under the floating Rings is a small area with a tiny platform for the player to use to climb back into the icy pool area. In the final version of the game, this was replaced with two springs, with one allowing the player to progress.
 * There is a small hole in the wall after the floating rings section that does not appear in the final version of the game.
 * A Super Ring next to the location of the small hole in the final version of the game is missing.
 * A Dash Panel leading into the second Icicle section is missing in the Autodemo.
 * The area below the second Icicle section is empty aside from a Spring and some fences. In the final version of the game, an Ice Ball was added as well as a circle of Rings.
 * There are six Icicles in the second Icicle section. In the final version of the game, the same changes to the first section were applied - the Icicle count was brought up to seven, and spikes were added nearby.
 * Two circles of Rings are missing from the area after the second Icicle section in the final version of the game.
 * The Spring in the area after the second Icicle section is also in a slightly different spot. The Rings were not corrected in the final version of the game.
 * The area with the floating ice block switch is empty aside from the switch. In the final version of the game, the switch was moved slightly to the left and a Hint Orb and fences were added.
 * The Point Marker after the ice blocks section is missing in this version.
 * The Dash Panels at the loop area are missing in this version.
 * There is no Hint Orb at the first Jump Panel.
 * The boxes around the first Jump Panel are slightly different than in the final version of the game.
 * There are three Jump Panels. In the final version of the game, a fourth one was added.
 * Three Super Rings in a small area to the left of where the Jump Panels end are missing in this version.
 * The end of the tunnel to the third section is not solid in this version.

Section 3

 * The gate at the start is facing the wrong way in this version.
 * The beginning of this section continues to play music. In the final version of the game, the Action Stage is silent until Sonic triggers the snowboarding segment.
 * Sonic does not make a screaming sound in the small cutscene where he notices the avalanche in this version.
 * Instead of focusing on the snowboard in the cutscene as Sonic walks off the platform he is standing on in the cutscene, the camera follows Sonic closely in this version.
 * The snowboard instantly appears under Sonic in this version.
 * Large rocks at the sides of the mountain are missing.
 * There are fewer icicles along the course than in the final version of the game.
 * Sonic's snowboard incorrectly plays the icicle breaking sound sometimes in this version.
 * There are three Dash Panels to the right after the avalanche section. In the final version of the game, there are two.
 * There are many dead trees on the mountain that were removed in the final version of the game.
 * The first falling ice arch was moved further up the mountain. One was also added on the side path to the right in the final version.
 * Sonic makes a different sound performing a trick in this version.
 * The first set of Trick Jump Panels are spread apart with a gap between them. In the final version of the game, they are united.
 * There are no Rings in the last caved area in this version.
 * There are no hot air balloons in this version.
 * There is a double Trick Jump Panel after the last cave. In the final version of the game, this was reduced to one ramp.
 * After the Ramps on the small land between the two Ramps is a Dash Panel and a line of rings that was removed from the final version.
 * The end of the Action Stage looks completely different; the capsule is in a slightly different spot compared to the final version of the game, there are no houses at the end of the Action Stage and there are more trees.

Big
Sonic has his own object layout for Big's section that is an earlier version of this Action Stage. There are many leftovers from the second section present that do not appear when playing as Big, such as Ring trails near the top of the Action Stage. However, many objects are incorrect in Sonic's version of the Action Stage. The differences for Big's version of Icecap compared to the final version of the game include:
 * There are Ice Balls here that were not moved to the final version of the game.
 * Big cannot break the breakable ice.
 * There is an underwater area under the smaller icy area at the start of the Action Stage. In the final version of the game, only the large icy are has an area under it.
 * The water is not animated and a lot of the underwater sections are not considered "underwater" by the game.
 * Much like Sonic, Big's Action Stage does not have spikes in it.
 * The area where there is an arrow of Rings in Sonic's version of the Action Stage in the final version of the game does not have any objects in this version. In the final version of the game, there is a High-Speed Shoes and a Spring.
 * The small icy pool halfway through Sonic's route is still icy in Big's section. In the final version of the game, it is a pool of water already.
 * The small platform to the side of the area where the Jump Panels end in Sonic's version has a rock on it in this version. In the final version of the game, this has been replaced with two Random Ring Item Boxes.
 * The areas on Sonic's route after the area with the arrow of Rings from the final version of the game are completely empty in this version. In the final version of the game, this area is filled with Springs, platforms, Rings and Item Boxes.

Lost World
There are few changes to Lost World's geometry; one being that the demo lacks the background walls from many of the areas throughout the Action Stage. However, the Action Stage has many differences in its object layout compared to the final version of the game. However, the only differences in the third area are that there is no Capsule and the door behind the starting point is missing.

Section 1

 * The starting room has an open ceiling that was covered up in the final version of the game.
 * There are flaming arrow shooters near the start of the Action Stage in this version.
 * There is an extra Boa Boa at the start of the Action Stage in this version.
 * There is a Dash Panel missing before the long tunnel of flaming blocks in this version.
 * There are no platforms after the long tunnel of flaming blocks in this version.
 * There is no Item Box over the spike pit in this version.
 * The checkpoint is missing here.
 * The camera messes up when the player enters the snake room.
 * The snake room is completely different. The platforms are in different locations and the route to complete the puzzle is different.

Section 2

 * The mirrors are missing in the dark room in the final version of the game.
 * There is a Boa Boa in the dark room that is replaced with a Ghola in this version.
 * There are no arrows at the end of the dark room in this version.
 * There are no Rings in the water slide in this version.
 * The layout of the puzzle is different. There are Boa Boas here and all the switches are situated on high platforms in different spots compared to the final version of the game.
 * The wall panels in the light room are already connected to each other rather than being separated from the beginning.
 * The switches for the wall panels in the light room have bright lights over them. This was removed in the final version of the game.

Final Egg
Final Egg has a duller appearance than its counterpart in the final version of the game. The first section is the only section featuring music and there is no section transitions.

Section 1

 * Sonic starts further back, in an area that is usually blocked off in the final version of the game.
 * There is no Egg Keeper at the start of the Action Stage in this version.
 * There are three Laser Field Blocks at the right at the start of the Action Stage. In the final version of the game, spiked balls were added and one Laser Field Block was moved to the left instead.
 * There are two Rings after the Laser Field Block section that are missing in the final version of the game.
 * The swinging spiked balls near the start swing much faster than in the final version of the game.
 * The platform with the Item Boxes and Springs around the swinging spiked balls are missing in this version.
 * There is a line of Rings missing before the first checkpoint area in this version.
 * The first checkpoint is missing, along with the Rings nearby in this version.
 * The Egg Keepers just after the first checkpoint area are further back than in the final version of the game.
 * There is another set of two Laser Field Blocks near the entrance to Amy's section in this version.
 * Amy's section is not blocked off in this version.
 * There are four Dash Panels in the large wall next to Amy's section. In the final version of the game, another one is added.
 * A machine claw is missing from nearby the entrance to Amy's section in this version.
 * In the room where Sonic and Amy's paths briefly meet, the only objects there are two Bladed Spinners and the Springs. In the final version of the game, more Spinners, Rings and a corner section containing lasers and Item Boxes were added.
 * The Springs in this room send Sonic slightly further in this version.
 * Two Rings after the second checkpoint are missing in this version.
 * There is a spike trap on the second conveyor belt that was removed in the final version of the game.
 * There are two rolling spike traps on the fourth conveyor belt. In the final version of the game, this was reduced to one.
 * The last three rolling cylinders in the Action Stage are in slightly different spots, preventing the section from being completed. They may be placed in accordance to an earlier design of the Action Stage.
 * The end of the Action Stage features a doorway. In the final version of the game, this is a slope that Sonic runs down.

Section 2

 * There are no death planes between the platforming sections in this version.
 * The piece of geometry out of bounds that is present in the final version of the game is also present in the autodemo. However, unlike the other paths, this piece still has the round appearance from the final version of the game.
 * The second section looks completely different, with the walls having a yellowish color scheme similar to the first section, rather than the bluish tones in the final version of the game. The start of the Action Stage is also a straight hallway rather than a slope Sonic runs down.
 * The objects seem to be slightly incorrect in this version, with some objects floating in odd places.
 * There are Rings of platforms around the walls separating the platforming sections. In the final version of the game, the only thing separating the platforming sections are death planes.
 * The platforming sections are empty in this version of the section. None of the floating platforms move, there are no enemies or Rings.
 * At the end of the first platform section at the start there is a platform on top of another one. In the final version of the game, the top platform is a Super Ring.
 * Before the first running section, the camera angle is completely different in this version.
 * There are no automated paths, Dash Panels or Rings in the small tunnels after the platforming sections in this version.
 * The running areas have different walls and open areas. In the final version, these are covered with glass. The floor in the running sections is also flat. In the final version, the tunnels are far more rounded.
 * The Springs after the first checkpoint usually send Sonic to the bottom of the Action Stage since the moving platforms are broken in this version.
 * To the right of the two Springs at the first checkpoint are a pipe and a platform that are not in the final version of the game.
 * The 1-Up after the second platforming section is missing in this version.
 * There are no Springs at the end of the second running section in this version.
 * There is no voice after pressing the Switch at the bottom of the platforming sections in this version.
 * The Rings over the switch are missing in this version.
 * The area below the raised switch is empty in this version.
 * The Bladed Spinners in front of the raised switch platform are missing in this version.
 * The Rings on the platform before the first swinging hammer are missing in this version.
 * The elevator and the Super Ring in front of it are missing in this version.
 * There are no objects in the area after the elevator in this version.
 * There are many more platforms at the last descent and they lead to a location slightly underneath the platform Sonic needs to go to in this version.
 * There are no Rings around the platform at the end of the Action Stage in this version.
 * The elevator at the end of the section starts lower down than in the final version of the game. This is around the Action Stage that the platforms nearby go down to.

Section 3

 * Sonic starts in the middle of the first room, rather than inside the elevator in this version.
 * Gamma uses Sonic's version of the Action Stage and has the same starting point as him.
 * The first room is empty aside from a square of four Rings. Furthermore, the area with the elevator does not exist in this version.
 * There is no voice in the first room in this version.
 * There are no Beats at all in the Action Stage in this version.
 * Sonic uses two Springs to get to the upper path in the second room. In the final version of the game, there is a ladder with spikes at the top there instead.
 * On the upper path there is a Laser Field Block and multiple Fans under the floor that are missing in the final version of the game.
 * The first checkpoint is missing in this version.
 * The Fan rooms consist entirely of close-together Fans. In the final version of the game, they have been set further apart and other objects (such as platforms and conveyor belts) are added to these rooms.
 * A section underneath the Fans with boxes, a Spring and 1-Up is missing in this version.
 * There is a duck enemy in the room between the first and second fan rooms. In the final version of the game, there are Rings forming a cross shape.
 * The second Fan room has a door that is not there in the final version of the game.
 * The room between the second and third Fans has a different camera angle in this version.
 * The Bladed Spinners in this room are Electro Spinners. In the final version of the game, they are not.
 * There is a Switch in the upper area of this room. In the final version of the game, it was replaced with three Item Boxes.
 * The amount of Bladed Spinners in room after the third set of Fans was reduced from three Electro Spinners to two Bladed Spinners.
 * The second Beat room has no Springs in this version.
 * The second Beat room has a platform in the upper area that does not exist in the final version of the game, and has Item Boxes containing High-Speed Shoes, a Super Ring and a 1-Up on it. In the final version of the game, the High-Speed Shoes and the 1-Up were moved to the pipes in the center of the room and the Super Ring was removed.
 * The small hole the player runs into before the checkpoint area is covered up, though the player can still enter the hole. The checkpoint here is also missing. Alternatively, the path where the player jumps over the small hole also looks different. It has no objects and leads into a long path of its own. In the final version of the game, these paths have objects and lead into long falling areas. The end of the running sections still exist in the final version of the game and are used after the falling areas.
 * The final Beat room lacks a door at the exit in this version.
 * There are four stationary Electro Spinners in the Sonic doll room. In the final version of the game, this was changed to three stationary normal Bladed Spinners and one Egg Keeper.
 * The Sonic-shaped cluster of Rings is missing in this version.
 * There is an Egg Keeper outside the Sonic doll room. In the final version of the game, this was changed to a checkpoint and some Rings.
 * The trail of Rings going up the curved path to the right is missing in this version.
 * The Sonic, Tails and Knuckles dolls are missing in this version.
 * The upper area of the room after the Sonic doll room is completely empty aside from a lone Egg Keeper that is not there in the final version of the game.
 * The checkpoint at the end of the room after the Sonic doll is missing in this version, much like the Rings around it.
 * The room before the Light Speed Dash Ring trail is empty. In the final version of the game, there are Egg Keepers, Bladed Spinners and a bonus area containing 1-Ups.
 * The Light Speed Dash trail reaches up higher at the end than in the final version of the game.
 * The giant Eggman face at the end of the Action Stage is missing in this version.
 * There is a tunnel to the right of the end of the area that Sonic can run down. In the final version of the game, this tunnel is blocked off.

Section 4
This unused section contains the room where Sonic meets the Egg Viper, though the small area he enters from at the start of the cutscene is missing. In the final version of the game, this section is in the same map as the Egg Viper boss fight (albeit far below the main arena) rather than an a part of Final Egg.

In this version only, there are two copies of the object file used for this section. The object file is outdated and the objects that appear in this area are the same as in the final version of the game, meaning the bizarre clusters of Capsules can be seen here too. The textures cannot be loaded, however.

Amy

 * ZERO does not immediately notice Amy at the start of the Action Stage in this version.
 * There is a Hint Orb in front of the starting point in this version.
 * After the first set of Springs, there are two Rings. In the final version of the game, this was changed to eight Springs.
 * There is only one Egg Keeper after the first Point Marker as Amy in this version.
 * There is a single Laser Field Block near the entrance to and inside Amy's section after ZERO breaks the wall. In the final version of the game, there are two Laser Field Blocks at these locations.
 * The Hint Orb in front of the elevator is missing in this version.
 * The crates to the left of the "Choose a door" room are missing in this version.
 * The large ledge near the end of the Action Stage has a crate nearby that Amy can use to get high enough to reach the ledge with a normal jump in this version.
 * Tikal's Hint Orb at the starting point reads:

Sky Deck
The second and third section of Sky Deck were given some minor changes for the final version of the game.

Sky Chase
There are some object changes in both acts of Sky Chase: There is also a third object layout that does not exist in the final version of the game. It references a number of bizarre objects, including the unused Sky Chase Dragon.
 * Act 1 only has one type of enemy (HODAI). In the final version, two more types (RENZAKO and ZAKOS) were added.
 * Act 1 and Act 2 have the same object layout.

Sand Hill
A file named "SETSBOARDS.BIN" is the only object file for Sand Hill in this version, and is much smaller than the ones used in the final version of the game, indicating that this Action Stage was one of the last implemented stage for the game.

Twinkle Circuit
The only section of Twinkle Circuit in the AutoDemo is an early model that does not resemble any of the courses used in the final version of the game. It has no music, objects, or textures and features multiple small inclined areas that are not seen anywhere in the final version of the game in any course.

Bosses
The maps for most of the boss arenas are in this version, even though the bosses themselves are not there (the Egg Viper has an area, but it appears to be empty).

Egg Hornet
The Egg Hornet's arena seems to use a very early model of the Mystic Ruins. None of the details present in the final version of the game can be seen here, much like the maps used for Casinopolis.

Chaos 2
While the arena itself does not have any interesting changes, Chaos 2 makes an appearance there. However, Chaos 2 will not move at all, nor will it try to attack. Chaos can still hurt the player with collision damage, though.

Perfect Chaos
The arena for Perfect Chaos is completely different compared to the final version of the game. The buildings that appear at the sides of the arena are also much taller than the ones used in the final version of the game. Furthermore, there is only one stretch of buildings, rather than the final version's loop shape. This suggests that the player would have kept using the same part of the arena for the entire fight rather than move through different areas.

The textures for this arena are present, but a few of the buildings do not have the correct textures, suggesting these textures may be for a different version of the arena.

Chao Garden
The maps for the Chao Gardens are very incomplete. The only one that does not crash the game is the Station Square Garden.

Station Square Garden
This garden is used for the prototypes images of Sonic Adventure. Its differences compared to the final version of the game include:
 * There are eight Chao here in the garden that spawn in set positions in this version.
 * The controls are disabled.
 * The camera is closer to Sonic and the player cannot zoom in and out like in the final version of the game.
 * Upon entering, the player drop a Rabbit, Deer, Kangaroo, Elephant, Lion, Gorilla, Mole, Koala, and Penguin.
 * The garden has no garden warps, elevator or stadium entrance. It is possible to fall out of the map through the elevator's location in this version.
 * There are no Hint Orbs in the garden.
 * The columns at the corners of the room are not solid in this version.
 * The trees do not drop nuts in this version.
 * The transporter says "NO DATA". Putting a Chao into it will cause the transporter to essentially remove the Chao; it will not come back out of the transporter and no VMU menu shows up.

Egg Carrier
The Egg Carrier Island is a piece of geometry ripped straight out of the third section Windy Valley. This is the garden used in the prototype Chao images.

Mystic Ruins
All that exists of the Mystic Ruins Garden is an early model similar to Casinopolis. The garden model is very different compared to the one in the final version of the game. Notable differences include the entrance being set on the other side of the garden. The only object in the garden is a single Ring located out of bounds, which is interesting considering that the Egg Carrier Island in the final version of the game has a similar out-of-bounds Ring.

Chao Race
The Chaos Race follows the same course as the one in the final version of the game, but there are some minor changes present along the course:
 * The Chao Stadium is missing in this version.
 * The area at the main starting point of the race has no hills on either side. There is also a very large wall to the left that was removed in the final version of the game.
 * The third platform that the Chao run to on the Amethyst Course is floating. In the final version of the game, it is attached to the ground.
 * The bridge connecting the second and third platforms is a regular bridge. In the final version of the game, it has a bridge of large blocks.
 * The arch over the path under the Amethyst Course's finish line is wider. In the final version of the game, the water is able to go through that part.
 * The island at the start of the Ruby Course is missing in this version.
 * There is an arch at the end of course that is not present in the final version of the game.

Gameplay differences

 * The player starts with two lives instead of four in this version.
 * The camera feels very different to the one in the final version of the game. Its rotation controls can sometimes be inverted depending on the current angle in the Autodemo.
 * Completing an Action Stage does not cause the Action Stage music to stop playing. It also plays the "Chaos Emerald" sound over the top of it. There is no results tally either.
 * The draw distance seems to be different in this version, notably the third section of Speed Highway seems to be smaller than both the prototype images and the final version of the game.
 * Instead of abruptly being taken to a black screen upon losing all the player's lives, the "GAME OVER" text is simply displayed onscreen. Because the screen hastily fades out to black, though, it is only visible for less than a second.
 * The transition from one section to another does not work correctly. The lighting and music will not update until the player either restarts or dies.

Characters differences

 * SonicAdventureAutodemo_SonicPose.png has a different action pose in this version. However, the old one is still used in a number of cutscenes in the final version of the game.
 * The standing animation for Sonic, Tails and Big is slightly faster in this version.
 * The characters do not have idle animations, nor do they talk after standing still for long periods of time in this version.
 * The animation list for the characters is different compared to the final version of the game.
 * Sonic is the only character that can push an object for an extended period of time. All other characters can only push briefly (Though as Sonic, a moving sound can be heard too).
 * Picking up objects is done in a very buggy way. Notably, it has difficulty choosing a target among multiple objects in this version.
 * Only Big and Sonic have the ability to put down a held object without throwing it. Gamma cannot pick up objects at all in this version.
 * The player cannot shake held objects in this version.
 * Tails is missing an animation for getting tired while flying in this version.
 * Tails and Amy are missing animations for jumping while carrying an object in this version.
 * Knuckles' gliding sound does not fade out and will continue for a short while after landing in this version.
 * Amy makes a sound when being locked onto by ZERO.
 * Amy's Piko Piko Hammer does not make any sound in this version.
 * Classic sounds are used for breathing an air bubble, getting hurt and dying in this version.
 * The opponent Sonic in Tails' Icecap does not speak in this version.
 * Drowning is very incomplete. The numbers that appear are very large and only appear for a fraction of a second in this version. There is also no drowning animation, as the game will just send the player back to the nearest checkpoint in this version.
 * Gamma will quickly go into his "holding gun" idle pose if he comes to a stop in this version.

Chao
The Chao system is very limited in comparison to the Chao system used in the final version of the game. All Chao in the garden will stay completely still until the player approaches them, upon where they will run up to the player continuously. If a Chao gets hurt by the player, they may decide to briefly run away from them instead.
 * The Chao make "Chao Chao!" sounds constantly in this version.
 * The animals do not affect the Chao's evolution in the same way as they do in the final version of the game.
 * All the Chao in the garden are child Chao here
 * The Chao do not die from abusing them too much in this version.
 * The animals will change a Chao's appearance instantly and more drastically than the animals in the final version of the game.
 * The "evolutions" are actually the child chao morphing beyond the limits there are in the final version of the game, giving the appearance of a different Chao.
 * Chao do not recognize water and run around underwater as if they were on land in this version.
 * Chao slide very far when thrown in this version.

Enemies
Some of the enemies in the game are slightly different compared to their counterparts in the final version of the game:
 * The Rhinotanks are missing their texture file, so they appear with incorrect textures in this version.
 * The player cannot pick up bombs thrown by Kikis in this version.
 * Enemies make fewer sounds than in the final version of the game. For example, Kikis make no sound when throwing bombs and Ice Balls do not make any sounds when moving around.
 * Ice Balls do not release animals upon exploding in this version.
 * ZERO has different "?" and "!" symbols, the latter making a sound usually reserved for the menu. His attack's lock-on target is also more solid in design compared to the final version of the game.
 * There is an untextured duck enemy that is present in the third section of Final Egg. It was removed from the final version of the game and replaced with an Egg Keeper.

Gimmicks

 * The Rocket platform added a lower part in the final version which is lacked in the Autodemo.
 * The Jump Panels were changed considerably for the final release. They have a flatter appearance in the final version of the game.
 * A Star Panel is used in the autodemo as the final landing point for the Jump Panels. It was removed in the final version of the game, but can still be found in the game's files (see "Unused models" section above).
 * Ramps do not make sounds and usually fail to launch the player to the correct point in this version.
 * The spike walls in Emerald Coast make no sounds and fall deeper into the ground than they do in the final version of the game.
 * The player cannot use the Homing Attack on all the Springs in this version. Some can be locked onto, but others cannot.
 * There is only type of Spring used in the autodemo; the large variant. In the final version of the game, a smaller variation is used as well.
 * Point Markers are not activated after respawning at them in this version.
 * Item Boxes have a green tint at the bottom that is not in the final version of the game.
 * Extra Life plays the "Chaos Emerald" jingle from Sonic the Hedgehog 2.
 * Capsules do not release animals in this version.
 * For that matter, animals make a "ring" sound instead of their regular sound when collected in this version.
 * The Cars in the third section of Speed Highway stop a much further distance away from the player than in the final version and cannot hurt them. They also have incorrect textures.
 * The Hint Orb's "This way!" is not voiced.
 * When a Random Item Box is broken, the "?" icon is displayed to the player. In the final version of the game, Random Item Boxes will display the icon corresponding to the amount of Rings given to the player.
 * There are no Explosion, Invincibility or Shield power-ups in this version (Their icons do not exist).
 * The ice block Switches in the second section of Icecap do not cause ice blocks to appear in this version.
 * Big cannot pick up the boulders in Icecap in this version.

Other differences
The mission cards present in the demo are very different to the ones used in the final version of the game. Even though the game only uses the Japanese versions, there are English versions of the cards in the game's files.
 * In the opening movie, Tails opens his mouth as he is flying away from the building. In the final he keeps his mouth closed.
 * There are extra Hint Orbs in Speed Highway than in the final version.
 * The cutscene with Tails outside Casinopolis is playing to another music track.
 * In the same cutscene, the textures for Tails' mouth, nose and eyes does not work properly. This also happens in the cutscene with Gamma and Sonic on the Egg Carrier.
 * In the cutscene with Amy and Gamma, there are Item Boxes inside one of the jail cells which are not there in the final version. Likewise, there would normally be a black Chao Egg inside one of the cells which is not there in this version.
 * Knuckles digs without the Shovel Claw.
 * In the cutscene with Amy and Sonic near Casinopolis, birdie has no wings.
 * In Final Egg, when Amy runs at top speed, her Piko Piko Hammer is not visible
 * The question mark and exclamation marks above ZERO's head look is different. Likewise, ZERO's target laser looks different and he has different sound effects.
 * In Final Egg, there is a 1-Up near the end of the demo that is not there in the final version.
 * In Gamma's cutscene with the other E-100 robots on the Egg Carrier, the purple robot looks like he has a white face rather than black.
 * In Big's cutscene, Froggy's model looks a bit odd. The colors also look quite dark.
 * When Big hooks Froggy, the "hit" music does not play.
 * Knuckles was going to have a complex list of combat-based moves in battle at some point, but they got scrapped.
 * In the game files on the Autodemo, there is a wallpaper showing Sonic with a Neutral Chao.
 * In the case of Amy's, her dress was going to reach her chest when she was falling.
 * In the autodemo, the Light Speed Attack and Light Speed Dash were mixed into one move and was executed differently. When using the attack, a blue orb appears and circles Sonic. Sonic can then home directly into a nearby enemy or along a trail of Rings. Also, either or  must be pressed each time the player wants to attack an enemy as opposed to the final where its targets all enemies at once.
 * The SEGA logo is a lot darker and smaller than the one used in the final version of the game.
 * In the Autodemo, all Extra Life icons face to the right with the exception of Sonic. This was changed in the final version of the game, where all the icons face to the left. The Tails, Knuckles, Amy and Big icons' transparency issues were not fixed, though.
 * The HUD is different in the Autodemo. The Rings icon is slightly different and there is a "Level" part that is not used anywhere in the final version of the game.
 * Big's HUD lacks the darkened numbers and his weight value is fixed at 12345g in the Autodemo. His life counter in the Autodemo is displayed in the top right of the screen in the form of lure icons.
 * The Chao icon for stress was changed in the final version of the game.
 * The billboard advertising Chao in Space in the final version of the game advertises something completely different in the Autodemo. This billboard can be seen in the final version of the game, but only during the Egg Walker fight. It was removed entirely in Sonic Adventure DX.
 * The pause menu uses an earlier design than the one in the final version of the game, though it cannot normally be seen as the pause menu is disabled. The pause menu sprite is still left in the game files on the final version of the game, but is not used.
 * There are two images reading "Start!" and "Goal" in the Autodemo's files. They seem to be some of the earliest files in the development.
 * Twenty nine music tracks are present in the build, some of which are used in Action Stages different from the final version of the game, or not used in the demo at all. Some of these unused tracks include:
 * Open Your Heart (Main Menu ver.)
 * Azure Blue World (Emerald Coast Act 1)
 * Windy and Ripply (Emerald Coast Act 2)
 * And... Fish Hits! (Big's Fishing)
 * Limestone Cave (Icecap Act 2)
 * Tricky Maze (Lost World Act 1)
 * Danger! Chased by Rock (Lost World Act 2)
 * Leading Lights (Lost World Act 3)
 * Crank the Heat Up!! (Final Egg Act 2)
 * Welcome to Station Square (Station Square)
 * Event: Strain (Cutscenes)
 * Event: The Past (Cutscenes)
 * Appearance: Knuckles (Cutscenes)
 * Many of the tracks in the Autdemo have noticeable differences from the final version of the game.

E3 Prototype

 * All the characters have all their Level Up Items enabled.
 * When the players select a character, they go to a list of Action Stages, like trial mode in the final version of the. The players does not get a list of all the Action Stages that were available in the final version. Also, the sub-Action Stages and regular Action Stages are in the same list, unlike the final game.
 * If the players do not move for a while (whether while playing or in a menu), they will return to the title screen.
 * A "Coming Soon" screen appears after playing an Action Stages.
 * Most of Knuckles' lines are different from the final version.

Gamecube preview
The GameCube preview is a direct port of the Dreamcast version of Sonic Adventure with debugging features enabled and a few changes added for the game's GameCube release. The date the disc image was created on was 2002/04/10.

Visual differences

 * The title screen uses a 2D artwork of Sonic over the final version's 3D artwork of Sonic.
 * The save icon is more simplistic in this version.
 * An Easy Menu, which is accessed by going to the Pause menu during gameplay and quitting.
 * PLAYER - Select the player character
 * STAGE - Change the Action Stage number by pressing left or Right and L or R to change the Act number.
 * MODE - Choose the game mode.
 * EVENT - Select a cutscene.
 * MEMORY CARD UTILITY - Opens up the memory card utility menu.

Mission Mode
The Mission Mode is incomplete. Only a handful of missions are programmed at that point and are mostly used for testing the game.

Prototype images differences

 * In the prototype screenshots, Big can be seen somewhere completely unrecognizable. It could possibly be the entrance to Twinkle Park, but this is unconfirmed.
 * Eggman is seen in an unknown cutscene with a Station Square in background, which never happened in the final version of the game.
 * Sonic Team's logo in the prototype sceneshots are different from the final with different sound effects.

Station Square

 * Near the beach in Station Square where Sonic and Tails chat, all the humans are missing from the prototype shot, along with their chairs.
 * Near Knuckles' entrance to Speed Highway, groups of people are walking out from the Entrance. These people are removed from the final version.
 * All of Station Square in general is filled with more humans across the multiple storylines than in the final version.
 * In images from Amy's storyline however, all the humans and cars are removed.
 * In an image from Knuckles' storyline, people can be seen waiting at the Kiosk in Station Square. This Kiosk does not have a line of people waiting at it in the final version. The humans present seem to be the same ones coming from the entrance to Knuckles' Speed Highway in the image above.
 * In an early shot from the Chaos 0 boss fight, the battle area has a more purple hue as opposed to the blue in the final version while Chaos 0 is more transparent and blue.
 * For the boss fight against Chaos 2, the lighting of Chaos is fairly off due to issues.
 * In the boss fight, the background was very dark and gloomy in the prototype images. In the final version, the chairs and windows are clearly visible in the background.

Egg Carrier

 * Inside Big's version of the Egg Carrier, the EGGMAN buttons are green and very small, whereas in the final version, they are orange and a lot larger
 * In Knuckles' version of the Egg Carrier Adventure Field interior, the floor is very lightly colored. In the final version, they are transparent with machinery visible behind them.
 * Some of Knuckles' punches make his back turn black.
 * When Sonic is talking to Eggman in the cutscene before the Chaos 6 fight, his mouth moves very differently from the final version. He has a huge bottom lip and seems to just jabber up and down.
 * The Egg Carrier's control room is differently colored from the final version.

Emerald Coast

 * In a shot, Sonic is sitting on a small sand island across from the beginning of his Action Stage. Unlike the final version though, but the beach is empty and Sonic does not strike his finishing pose for clearing said Action Stage. There is also another image showing Sonic doing his pose in a place different from the Goal in the final version.
 * The beach in Sonic's version is not filled with any Badniks.
 * In Big's gameplay, Froggy was originally in a secret passage, and Big had to catch him there instead of near the lighthouse.

Ice Cap

 * At one point, a peculiar bridge with an enemy on it appear in Sonic's version of the Ice Cap. Sonic would use this bridge in the early version of the game, most likely instead of the rocket in the final version to get to the second area. Other images shows it during the avalanche section. A bridge can be seen in the final version of the game at this point, but it is very difficult.
 * Some of Sonic's snowboarding tricks are deleted in the final version.
 * In different screenshots, there were no large walls surrounding the Ice Cap, leaving the background visible. Also the whole area was surrounded by trees much different to the ones interacted with on the course.
 * There was a trick ramp that is split in half with a score counter which appeared in the prototype version.
 * There were also some "beta" trees which Sonic would fly through due to the ramp which were removed.
 * The camera angle when Tails escapes the avalanche is different from the final version.
 * Big's animation is seen from a different angle and the camera is further away from him.

Casinopolis

 * When Sonic is showering in Casinopolis, the shower is different. He also does not do his 'cleaning' animation.

Hot Shelter

 * In Amy's version of the Action Stage, Amy is shown doing her victory pose in an area that does not exist in the final game.
 * There is an area that does not exist in the entirety of the Action Stage. It looks like the power cube area, but the floor is very different and there are no recesses or places to put the power cubes in.

Final Egg

 * Amy Rose's version of the Final Egg has no enemies and only includes ZERO.

Chao

 * In some screenshots, Sonic is seen wandering around in what could be the very first version of the Chao Garden, part of the original Windy Valley. The Chao all appear to be following Sonic around. This area is quite basic, using a completely flat surface with a few ruins like model surrounding it. The most
 * In a prototype video, the 3D model of a Chao is shown. This shows that at some point the Chao were yellow/blue, before they made the decision to make them green/blue like in the final. It was later changed back in other games. Also, their wings are completely different.
 * In a prototype video one can see some Chao Adventure animations from the VMU game. When the Chao meets Sonic, Sonic's animation is very different from the final. For comparison, the final sprite is stuck to the side in the image above.

Lost World

 * The room with moving fire blocks have different textures
 * The first Star Post inside the primal world section is moved further away from their position in the final version.
 * The primal world section lacks the floor texture seen in the final version.
 * At the beginning of the Action Stage in the final version, Sonic can easily drop down the first steps. In the prototype version Sonic has quite some difficulty moving along these steps.
 * Further down the beginning of the Action Stage in the protoype version of the game is a hazard area with fire arrows, and an E-05 Boa-Boa. Both these objects are removed from this area in the final version.
 * In the room with the rising water and the snake transport, the snake transport would float in midair in the prototype version.
 * In the waterslide section which goes down a waterfall, Sonic was originally running down the waterway in the prototype version rather than sliding down it in the final version.
 * Knuckles is lacking the Shovel Claws in the prototype videos.
 * In the prototype video and Japanese advertisements, Knuckles was seen in the room with the Perfect Chaos mural with Sonic reaches in his version of this Action Stage. However, Knuckles cannot enter this section in the final version without performing glitches.

Trivia

 * In the final version of the game, there are some leftovers from the beta that were surprisingly not deleted and can still be seen without using any tools or software. These are likely developer oversights since the game has gone through a number of revisions:
 * When Amy is remembering "her old times" the beta version of Windy Valley can be seen with an object prominent in the Red Hot Skull portion of Red Mountain
 * In Sonic's pinball table located in Casinopolis, the images of Sonic, Tails, Knuckles, Amy and Eggman that are in the slot machine are in their classic styles.
 * In Gamma's tutorial gameplay, E-104 Epsilon has Gamma's color design (except for his laser cannons).
 * In Sonic's tutorial gameplay, the beta version of Windy Valley can be seen in the screenshots.
 * For whatever reason, a few leftover tracks from the Chao Gardens in Sonic Adventure 2: Battle exist in Sonic Adventure DX: Director's Cut.