Stage Differences Something in each Stage was generally changed or enhanced in some way for Battle.
Opening Sequences, Title Screens, and Menus
The Dreamcast version does not feature the short opening sequence with Sonic and Shadow at Radical Highway before the title screen. There is simply a small intro clip of the title of the game popping into view extravagantly in space, the Dreamcast intro is still in the game, just broken.
The title screens are different, albeit using the same music. The GameCube version features a scrolling background of the game's main characters, whereas the Dreamcast version is not animated.
With the exception of the main menu, the background of each menu in the Dreamcast version uses art of Sonic and Shadow's faces under different sets of colors. In the GameCube version, a different background is used featuring all the characters instead and does not change colors. The functionality for the color-changing menus was not removed (as can be seen in the leftovers of the original 2P menu), but for whatever reason is not compatible with the GameCube version's background.
The demo mode that appears after the title screen remains idle for a bit is changed.
On the Dreamcast, the demo is of a character playing one of their stages to their character theme. So for example, the first demo is of Sonic playing City Escape with "It Doesn't Matter" playing as the music. There's a demo for each character.
On the GameCube, the demo is of a two-player match played under usual conditions. The original demos are still in the game, but they aren't used.
"SONIC ADVENTURE 2" in various fonts can be seen scrolling in the background of menus in the Dreamcast version. In the GameCube version, this was replaced with various floating orbs.
The two player option says "2P Play" on the Dreamcast and "2P Battle" on the GameCube.
Seeing as the GameCube version cannot get online, the Home Page option on the main menu was removed.
The kart race menu in the Dreamcast version featured a 4th course option where players could choose downloaded tracks. As the GameCube version had no use for it, it was removed for SA2B.
Unlockable skins were added to each character in the Kart Race. Two of the special karts used for downloaded tracks in the Dreamcast version (High Speed Trial Sonic and Eggrobo) were included among these as alts for Sonic and Rouge respectively.
On the Dreamcast, the sound test is located in the options menu. In the GameCube version, the sound test slot in the options menu was replaced with the ability to delete multiplayer records. The sound test was moved from the Options menu to the Extras menu in order to replace the Download Event option that was on the Dreamcast, which was for reading downloadable themes for the menu and alternate costumes/karts from the VMU.
The icon for changing between stereo and mono was changed. In the Dreamcast version, it's a megaphone-looking speaker with sound waves coming out of it. On the GameCube, this was changed to a modern-looking speaker emitting sound waves.
The TV settings menu option no longer appears in the GameCube version's options menu.
When the game is switched to Japanese text, the Dreamcast version doesn't translate the main menu or the "Now Loading" indicator into Japanese. This is all translated in the GameCube version.
The Dreamcast needed to download menu themes from the game's website. As the GameCube version doesn't have an equivalent for this, it had to make a lot of changes. The themes for the 6 main characters are available from the start of the game, with no download required. The Amy, Maria and Omochao themes can be bought at the Black Market in Chao World and the secretary's theme is unlocked by rotating through the theme select a certain number of times. The Christmas and Halloween themes were removed.
The order of the themes, as well as the design of each theme was revised for the GameCube version. In the Dreamcast version, themes are color swaps of the default menu background with character art overlaid in the Options menu. In the GameCube version, an entirely new graphic is used instead.
Despite not being able to be accessed without the use of cheats, the game's hidden debug menu was also enhanced for the GameCube release.
The title graphic was changed for the GameCube version. Interestingly, Sonic and Shadow both still use their Dreamcast models in the SA2B version.
The Japanese text on the title was changed.
In the Dreamcast version, there's text around the logo that reads PSO, ver.2, ガンバレ (Do your best), ガンバロウ ("Let's do our best") and ソニ２ (SA2). There's also a much larger line of text at the bottom that says 祝！日本ゲーム大賞受賞 ("Congratulations! Japan Game Grand Prize Winner").
In the GameCube version, there's text above and below the logo. The above line being いつもよりたくさんだしてます ("getting out a lot more than usual") and 行楽のお供に ("to accompany for a picnic").
The text at the top of the screen to toggle missions and upgrades does not appear in the GameCube version unless the player selects "1P ONLY" or "1P DEMO".
Stage Selection was reworked for the GameCube version. In the Dreamcast version, all stages are listed and are ordered by their internal ID, but in the GameCube version it only lists stages for the selected character and in the order they're played in.
A timestamp was added to the Event menu. It lists the version as 07 November 2000 at 17:14:20, with the year most likely being a typo as the listed date would mean it predates SA2:The Trial.
Both versions are color-coded, but for different reasons.
The Dreamcast version lists "New Event" entries as Yellow (None are listed), "Complete Event" entries as Green and "Incomplete Event" entries as Gray.
The GameCube version separates events by "Normal", "Big" and "SFD", with Big events being two scenes from Last story (The cutscene before Cannon's Core and the cutscene where Sonic and Shadow transform) and SFD events being the game's prerendered SFD files.
The upgrade toggle was added to the event menu in the GameCube version.
Events consisting only of time stamps (Such as those before in-stage cutscenes) are not listed in the GameCube version of the menu.
All characters and objects are lit differently in the GameCube version. This is due to shaders used in the original game that aren't present in the GameCube version, so the object lighting looks slightly bland in comparison.
The draw distance for objects is greatly extended in the GameCube version.
All of the main character models were enhanced slightly for the GameCube release. (Note: Aside from select moments, these changes do not appear in cutscenes.)
Eggman's mech was given a flashlight effect that lights up anything in front of him.
The "Now Saving"/"Now Loading" icon that appears in the upper right corner of the screen doubles as a progress bar that gradually fills as the save/load progresses. While the icon remains in the GameCube version, it does not act as a progress bar anymore.
The Life box icons were changed slightly. Notably, Sonic's icon uses a more up-to-date model than the Dreamcast version.
When a character uses a special move during a battle/race, the Dreamcast version has a background (with inverted/monochrome colors) specific to that level, showing the level. Meanwhile, a fairly opaque background was added for every playable character on the GameCube version.
The GUN robots that use shields (Shield Hunters) had their shields redesigned for the GameCube release. The shields on the Dreamcast looked as though they were made to cover a little bit more of the robot, but the GameCube version made them narrower and more revealing. There's also a "01" shield variant in the Dreamcast version that was removed in the GameCube version.
The Beetle robots have a GUN logo on their foreheads on the Dreamcast version. It's still there in the GameCube version, but due to a layering error it doesn't show up. This same problem can be seen on Eggman's mech.
The item balloons and the bodies of Artificial Chaos are slightly transparent on the Dreamcast. On the GameCube, they were made fully opaque.
The SOAP posters in City Escape, Radical Highway and Mission Street have not only been modified but also swapped around. City Escape uses Radical Highway's design, Radical Highway uses Mission Street's design and Mission Street uses City Escape's design:
The "TIME EXTENDED" text in Route 101/280 does not overlap the pause menu in the GameCube version.
A border was added to the Mystic Melody doors.
The bright light under the player when travelling over transparent floors in the ARK stages looks slightly different.
All of Big the Cat's cameos in levels were removed (some of them replaced with a ring), though he can still be seen in some cutscenes by rapidly pressing the A or B buttons.
Knuckles and Rouge can climb on and dig into walls underwater on the Dreamcast. This ability was taken out on the GameCube. This is likely because this ability was actually a glitch, seeing as the Dreamcast version never necessitates the use of it, much less even mentions it.
When Knuckles and Rouge are close to one of their objectives, an exclamation point in a red bubble pops up above their heads in the GameCube version. This makes pinpointing a hidden emerald/key much easier.
When Sonic completes a stage, while his pose is the same between versions, he doesn't directly look at the camera on the Dreamcast. On the GameCube, he looks directly into the camera.
On the Dreamcast, when Eggman or Tails (or any other mech character) gets hit with a shield on, they lose health on top of losing the shield. On the GameCube, they only lose the shield, no health, like they should.
The emblem distribution for Chao World is completely different between versions:
In the Dreamcast version, Chao World awards 10 emblems, all of which are obtained by completing each of the five groups of races in Chao Race. Each group awards two emblems each.
In the GameCube version, Chao World now only awards nine emblems. Chao Race awards five emblems for completing each group of races, with the remaining four awarded by clearing the four levels of Chao Karate. The absent 10th emblem is now awarded for achieving A Ranks in every mission of Cannon's Core.
The multiplayer was overhauled for the GameCube release, which is the entire reason why "Battle" was tacked onto the end of the title on GameCube.
Multiplayer now runs at 60 FPS. It was locked to 30 on Dreamcast.
In the Dreamcast version, teams are determined and then the type of match is chosen with the alternate option to choose a stage manually. In the GameCube version, the type of match is chosen first, followed by character selection and a mandatory stage select.
The 2 Player menu was heavily redesigned for the GameCube version, with unique music and a new menu featuring the main cast of characters standing in the background. In the Dreamcast version, the 2 Player menu is more like the story select - even using the same music and team icons.
Selecting the type of match is done through the 2 Player menu itself in the GameCube version. In the original game, the match types were separated into "Action", Kart Racing and Chao Racing on the main menu. The match select within the "Action" menu was merged with the main 2P menu in the GameCube version.
In the Dreamcast version, one player is set to Hero and the other is set to Dark. In the GameCube version, individual characters are selected instead. This allows match combinations that were not possible in the Dreamcast version (such as Sonic vs. Amy).
Alternate costumes are accessed differently. In the Dreamcast version, they're found by pressing Left or Right (depending on the player) while highlighting the preferred match or stage. In the GameCube version, they're found by pressing Up while highlighting the corresponding characters in the character select.
The stage select is significantly different. In the Dreamcast version, a list is shown alongside the icons of characters compatible with each stage. In the GameCube version stages are ordered on a tiered list, from short to long. Each stage is represented by a thumbnail and a name display when highlighted.
21 new stages were added to the GameCube version. The 9 stages found in the original game were listed as Level 3 stages (Excluding Weapons Bed, which is Level 2).
A "Battle Option" menu was added to the GameCube version via stage select that includes settings for handicaps (stronger special attacks), time limits (usually around 5 minutes) and the number of matches. In the Dreamcast version, there are no handicaps or time limits and the number of battles is solely determined by whether the player started a match through the main menu (Best of 3) or the stage select (Single match).
In the Dreamcast version, the alternate costumes for each character are unlocked when you complete every mission available to that character. The alternate characters would unlock when the player gets A Ranks in every mission as a specific character. In the GameCube version, the alternate characters are available by default and have new, unique abilities and fitting sound effects (in the Dreamcast version only Amy had unique sounds). In turn, new karts would unlock for the kart racing mode when a player completes every mission as a character, and achieving all A Ranks now unlocks the costumes.
Each alternate costume was redesigned in some way. Tails is the only character who retains the same costume from the Dreamcast version, albeit modified.
Each character was given a unique background for their special attack animations in the GameCube version.
Eggman has a different intro camera.
All of the alternate characters are the same in the GameCube version with the exception of one. In the Dreamcast version, Eggman's alternate character slot is occupied by Big the Cat, who rides in Eggman's walker. In the GameCube version, Big was replaced with a Dark version of the Chao Walker.
The Dreamcast version of the game included a number of seasonal costumes for Christmas and Halloween in 2 Player mode. These costumes could be enabled through special menu themes that (like all themes in the game) were unlocked via downloads to the VMU. They were removed entirely from the GameCube version.
Like the other alternate costumes in the original game, the seasonal outfits are completely aesthetic changes and do not affect gameplay at all.
The Chao World underwent many changes between the two versions as well.
When picking up a Chao, the Dreamcast version only displays the Chao's name in a text bubble above its head. A window displaying the Chao's stats is used instead for the GameCube version, with the name being moved to the top of it instead of being in a bubble.
Chao stats range from 0-9999 in the Dreamcast version (However, the last digit is hidden) and are increased every time a Chao is given an animal or drive. In the GameCube version, stats increase via level ups with a cap of 99 levels in place. Due to this cap, the max possible value a stat can be in the GameCube version without cheats is 3266. The magnitude of the stats was adjusted accordingly.
Grades from S to E were added to determine how many points are added to each stat upon level up. This means that every Chao has a different stat cap in the GameCube version, whereas the Dreamcast version's rate is constant for every Chao.
Many new breeds were added to the GameCube version, with the new breeds including Two-tone and Mono-tone Colored Chao as well as their shiny variants. 4 New Jewel Chao were also added (Aquamarine, Peridot, Topaz, Onyx). However, the Moon Chao is unobtainable in the GameCube version.
The types of fruit that can be obtained are different, as well as the method of obtaining them. The Dreamcast version's seeds could be obtained through Chao Adventure, whereas the GameCube version's are bought via the Black Market.
Chao cocoons are white in the original game, but they were given colors in the GameCube version. Blue for evolution, Pink for reincarnation and Gray for death.
Hidden Tails, Knuckles and Amy Chao were added to the GameCube version. The Tails Chao could be obtained through Phantasy Star Online while the other two were obtained via events. Currently, the only way to legitimately obtain the Knuckles and Amy Chao is to transfer them from a certain catalog disc.
In the Dreamcast version, the player can still use attacks in the gardens with just as much ease as if they were in a level. While they can still be selected on the action command, the attacks in the GameCube version are not automatically available so that players wouldn't accidentally hit their Chao. It was also made impossible to somersault or Spin Dash.
The music used in the lobby was changed to the race entrance theme from Sonic Adventure. The music that was used in the Dreamcast version's lobby is instead used for the Chao Stadium entrance.
Omochao greets the player with "Welcome to Chao world!" upon entering the Chao Lobby in the Dreamcast version. His welcome is removed from the GameCube release. Instead, a title graphic shows upon entering (as well as for any other place entered in Chao World).
The menu for leaving the Chao World was redesigned for the GameCube release.
In the Dreamcast version, you can see the background behind the exit to the Chao Garden. The GameCube version turned this into a more natural cave exit.
The skybox in the Chao Garden is centered around and follows the player in the Dreamcast version just like the ones in the main stages do. In the GameCube version, it's stationary. However, it should be noted that this only applies to the first garden and that the Hero and Dark Garden's skyboxes are stationary in all versions of the game.
Each Garden's decorations were moved around, as well as some trees in case of the Dark Garden.
In the Hero Garden, there is a river and bridge in the Dreamcast version. These were taken out in the GameCube version, and the pond around the fountain was made bigger to compensate.
The pools in the Dark and Hero Garden were made shallower, likely to prevent Tails from drowning.
In the Dark Garden, there is a large cliff with a cave hidden underneath. All of that was removed and replaced with a tree. A large branch from the mountain was reused for said tree, with the bottom of the cage on it even being made solid.
Also in the Dark Garden, there were submerged steps in the blood pool that made it have various depths. These were removed on the GameCube - it's completely flat. The decorations, like in the Hero Garden, were also rearranged slightly.
Animals and dropped fruits are removed when the player leaves the garden in the Dreamcast version, but remain in the GameCube version and can actually be brought to other gardens through the lobby.
The amount of trees was increased from 2 to 3 in the GameCube version, with the added tree occupying a tree seed spot.
The design of the transporters was changed from a VMU to a GBA to fit the platform transition. The GBA transporters only have a single design, whereas the VMU ones fit the theme of each garden.
The transporter menu was redesigned heavily in the GameCube version. Whereas the Dreamcast version can only transfer a Chao to/from VMUs, the GameCube version allows Chao to be moved between GBAs and Memory cards, as well as the feature to remove a Chao altogether.
The Chao Transporter is stylized in the Hero and Dark Gardens in the Dreamcast version, while in the GameCube version the same model for the transporter is used in all gardens.
A new minigame was added - Chao Karate. While the Dreamcast version goes straight to the race entrance upon entering the stadium, the GameCube version presents another menu first asking whether the player wants to do Races or Karate.
The music used in the race entrance was changed. The original theme was repurposed for the Chao Transporter.
Four emblems from the challenge races were relocated to the Karate. A fifth emblem was redirected to all A Ranks on Cannon's Core.
The lights on the Chao statue in the Race entrance are brighter in the GameCube version. The statue is also missing the platform it was standing on in the Dreamcast version.
The area behind the numbered doors is a wall in the Dreamcast version, but black fog in the GameCube version.
The amount of Chao that can participate in Party Race was reduced from 8 to 4.
The Chao selection screen was revised for the GameCube version, adding a display for the Chao's stats:
Names no longer appear above the heads of Chao at the beginning of a race. The names given to Chacron and the Ranger Chao (GREEN, YELLOW, RED, BLUE, PINK) are thus never displayed.
The Cockroach Chao racers were changed from Black to Onyx Chao for the GameCube version. They were also given animal parts from dragons to appear more cockroach-like.
The "Kid Troops Chao Rangers" were given animal parts and changed into shiny Chao. The unobtainable breeds they use in the Dreamcast version were removed.
The Kindergarten was mainly adjusted to accommodate features from Chao Adventure and the Dreamcast's Internet features that couldn't be ported to the GameCube.
Two new rooms were added: The Fortune Teller and the Black Market. Both of these are replacements for features that were unable to be ported from the original game (The Fortune Teller being the VMU's naming abilities and the Black Market being the replacement for the Dreamcast's online version).
The bulletin board offers to launch the player to an online Chao message board, in-game, on the Dreamcast. Since the GameCube version can't connect to the Internet, it simply refers the player to the game's website with the URL.
The small clip of the player character walking up to or away from the Kindergarten is skippable on the GameCube when it wasn't on the Dreamcast.
In the Dreamcast version, there's a small table in the middle of the Kindergarten that serves no purpose except for decoration. It was removed in the GameCube version.
The music in the Classroom changes to Chao singing in the GameCube version, whereas in the Dreamcast version, the music doesn't change at all.
There are captions that pop up in the upper left corner in both versions of the game when an entrance to something in the Kindergarten is approached. However, in the GameCube version there is a colored backing for it so that it is more noticeable.
Most room text boxes in the Kindergarten (other than the Classroom) are transparent in the GameCube version.
In the Dreamcast version, the introductory text for the Principal in the Kindergarten progresses on its own eventually if no buttons are pressed. In the GameCube version, they only progress the text when the player presses a button.
The headers for each room in the Kindergarten were given a minor redesign.
The objects in the background in for the Principal's room were flipped to the opposite side of the room.
For some reason, the Principal's line "Chao doctor will give you tips on how to raise your Chao." does not complete in the GameCube version. Instead, he just says "Chao doctor will give you tips".
The Principal's tutorial text was given a considerable revamp in the GameCube version. The categories were reorganised and all of the text was re-translated.
The Health Center's functions were redesigned in the GameCube version. In the Dreamcast version, the doctor examines the Chao and then says a line related to a random quality of the Chao (e.g. "This Chao likes Sonic."). The GameCube version removes this and instead offers a "Medical Chart" of the Chao's details. The Examine option in the GameCube version is only used to check if the Chao is sick.
There are many slight modifications to most of the cutscenes between the two versions. In general...
In the Dreamcast version, some scenes (President and ARK) ran at 30 FPS. On GameCube, all scenes are at 60 FPS.
FMVs were upgraded from 480×366 to 640×480, and were uncropped.
Some camera angles were altered slightly from the GameCube, ranging from more relevant shots to simple zoom-outs.
The way lights and shadows work is different between the two versions. The GameCube version removed most of the shadows that appeared in the Dreamcast version. This is because the shadows didn't have any kind of fading, so they looked awkward in the cutscene sometimes. The lighting, however, was changed for the worse. On the GameCube version, bright lights affect the characters, but don't affect any upgrades that they're wearing. Also, there are rays of light from specific light sources that are missing in the GameCube version. On the Dreamcast, bright lights do affect character upgrades, and there are light rays where necessary. Characters also look significantly darker in ports.
The Eclipse Cannon's control panel monitor is very incomplete when Rouge accesses it and in the Dark story's ending. In the Dreamcast version, elements displayed on its screen are created in-game, show relevant information and progress alongside the scene (noticeable using the time manipulation features of the Debug menu's Event Test). In the GameCube version, the screen is a movie file of what looks to be a very incomplete port of the original game's version - with a lot of elements from the original appearing crushed into the top left corner.
Emeralds in the Eclipse Cannon were edited to stand out more in the GameCube version.
In general, the "Off" mode of all screens looks different in the GameCube version.
Earth's texture was changed, it's a lot smaller and has faded edges. Though this has the side-effect of leaving empty space in cutscenes, and the planet wasn't updated in stages or some cutscenes.
In most scenes with Chaos Emeralds in the Eclipse Cannon, they are more vibrant.
Despite the in-game models changing, most cutscenes still use the Dreamcast models. Some models have been ported, but aside from one scene, only Sonic's was changed. His belly is a lot smaller than the Dreamcast version. This is because unlike SA1, cutscenes are self-contained, meaning they have to be all changed individually.
Knuckles' eyes don't clip as-much during cutscenes. He also looks less angry in most scenes despite his model being unchanged.
Amy's noticeably cross-eyed due to her pupils being made larger. Her teeth were also made red, making it look like she has none.
There are many layering issues in the GameCube version. Usually, this appears in the form of lights showing up behind objects, but it also has effects such as the monitor in Eggman's base displaying information in the background and Chaos Emeralds being notably distorted.
Maria is missing eyelashes in the GameCube version.
The ARK's main room shows reflections in the glass that are lost in the GameCube version. This is because they're all drawn behind the space background.
The intro was revised far more than any other scene in the game:
Clouds are slightly smaller in the GameCube version.
Camera movement is more fluid and Sonic uses his updated model through most of the cutscene.
It's no-longer possible to see the door floating in the background.
Sonic does not incorrectly wear his regular shoes briefly in the GameCube version.
Lens-flares are missing throughout the scene, though the light source is still present.
The helicopter's blades disappear for one shot.
The city is lit a dull-gray in Battle.
After City Escape
The scene where Sonic and Shadow meet for the first time was also heavily revised compared to others:
Sonic uses his updated model a lot during this scene too, and is the only instance where a character other than Sonic uses their GameCube model.
Sonic loses some expressions in the GameCube version of this scene - his ear moves in the Dreamcast version when he hears Shadow land on the crashed Big Foot and his eyes squint when Shadow leaves, but these were lost in the GameCube version.
The pilot of the crashed Big Foot is missing in the GameCube version. It's actually still there, but can't be seen due to a transparency error with the glass.
Sonic and Shadow are very bright in the GameCube version. The lighting on the updated models just seems to be incomplete, as more accurate lighting is used before Sonic notices Shadow.
The camera is further away from Shadow when he performs Chaos Control. The green-flash is also missing during the shot.
Some background objects were added in the GameCube version, such as signs.
When Shadow leaves, his skin lights up but not his spines.
Knuckles Meets Rouge
When Knuckles and Rouge first meet, Rouge screams after the shot of Eggman flops onto his dashboard, followed by her throttling Knuckles. In the GameCube version, Rouge screams the exact moment Knuckles shatters the Master Emerald, obscuring Eggman's line and causing the cutscene to briefly desync.
Eggman's mobile has a more detailed shadow in the GameCube version. Its window is also missing.
Tails Flies to Prison Island
Tails' cannon is missing markings.
Amy's lit brightly in the GameCube version.
Tails Saves Amy
For unknown reasons, there's an untextured door in the background.
Amy Frees Sonic
The bars of Sonic's cell cast shadows in the Dreamcast version that aren't present in the GameCube version.
Before Mission Street
The building shadow pattern was replaced with something more generic in the GameCube version.
For unknown reasons, the level geometry for Sky Rail somehow made it behind the cutscene geometry. Though it can't be seen unless someone uses Dolphin's free cam option.
When the president talks with Eggman in his limo, there is a little more interference added to Eggman's video screen on the GameCube version.
The bridge was also given a shadow and some background objects are drawn correctly in the GameCube version.
The camera clips through the bridge in the GameCube version, and some transparency issues with the trees can be seen.
The limo's windows are tinted on the inside.
The president's suit is displaying incorrectly in the GameCube version, despite the texture being unchanged.
Tails Goes In
When Sonic, Tails, Knuckles, and Amy find the pyramid where Eggman's base is located, a lens flare is present in the original game that is not in the GameCube version.
Knuckles' hand just looks wrong in the GameCube version.
After Pyramid Cave
The glowing Eggman signs are missing in the GameCube version.
Sonic's thumbs up pose to Knuckles was revised with a new camera and updated model. Though his wink was removed.
Sonic Climbs Onto the Shuttle
The FMV in which Sonic boards the shuttle mistakenly depicts him with his regular shoes in the Dreamcast version, instead of his redesigned Soap sneakers. This was fixed for the GameCube version.
Tails' Fake Emerald
When Sonic, Tails, and Amy meet in a hallway in the ARK, the hallway they're in has been redesigned slightly. Notably, there is now a red stripe along the floor and walls that follows the rest of the patterns.
Tails' emerald box lock looked noticeably mangled in the Dreamcast version, this was fixed in the GameCube version.
Rouges Gives Knuckles the Master Emerald Shards
The background looks different for the first few shots. This is because a transparent background from the Dreamcast version is now opaque. Though it should be noted that it is invisible on Dreamcast unless the camera is close to it.
Sonic noticeably did not walk into the circular area that would encapsulate him in the Dreamcast version, but appears there when he's captured. He correctly enters the circle in the GameCube version.
Sonic's reaction to being encapsulated was revised.
There is a lens on Eggman's gun that was removed from the GameCube version.
When Sonic is launched out of ARK, the planet is unfinished.
Before Sonic vs. Shadow 2
The Emerald is missing a shine effect.
Sonic uses his updated model when he holds the Fake Emerald and when he runs into the distance before fighting Shadow.
Tails' alarm is higher pitched in the GameCube version.
A window shine is missing.
Instead of lighting, the screen just flashes red.
A large door is missing behind Eggman when he first appears in the GameCube version.
Eggman Releases Shadow
Eggman enters the password to release Shadow, there is a slight glow from the screen that is lost in the GameCube version. It's still there, but is drawn behind the wall.
Shadow's capsule glows more in the GameCube version.
Rouge Meets Knuckles
All of the changes made to Knuckles' version of the scene applies here.
New camera angles were added in the GameCube version.
Rouge Breaks into Eggman's Base
When Rouge breaks into Eggman's quarters and looks through his computer, text from the transparent screen is overlayed over Rouge looking at the computer in the GameCube version, making it look more like the camera is behind the transparent screen. Again, the glow from the screen that hits Rouge is lost on the GameCube.
The ARK's True Power
When Shadow announces the true power of the ARK to Eggman, a flash of light appears. However, in the GameCube version a layering bug causes it to appear behind the control panel and Shadow's spines, yet in front of Shadow's face.
Amy Confuses Shadow for Sonic
When Amy hugs Shadow, her head is in a different position - leaving her looking slightly cross eyed.
Shadow Runs to Save Rouge
When Shadow decides to go save Rouge, Rouge is surrounded by the three Chaos Emeralds that she just collected in the Dreamcast version when the scene cuts to her. These are missing in the GameCube version.
After Shadow vs. Sonic
The way Shadow leaves Sonic is different between versions. On the Dreamcast, Shadow slips away, while on the GameCube he jumps.
When Shadow lands at Rouge's location, his movement is different and more fluid than the Dreamcast version.
The camera on Eggman's bomb is different. It also isn't drawn correctly in the GameCube version.
Shadow Spots Tails
The camera when Shadow first spots Tails at Sky Rail is different.
Shadow watches Tails fly past after having completed Sky Rail, the background for the mountain is lower in the Dreamcast version than it is in the GameCube version, making it look as though Shadow and Tails are at a higher altitude on the Dreamcast.
In the Dreamcast version, part of the level geometry appeared in-front of the fog, this was fixed in the GameCube version.
When Rouge looks through the computer on the ARK, completely different screens are shown to her between versions.
Rouge's hand is different when she calls Eggman.
When Eggman discovers two Emerald readings at his base, he enlarges a map of the ARK. In the GameCube version, this briefly appears at first to be a copy of the same view of Sonic he was already looking at.
When Eggman leaves Shadow at his base, the camera is different at the end of the scene.
When Rouge confronts Shadow about the "ultimate life-form" in the ARK's database, in the Dreamcast the music played is Fly In The Freedom (Rouge's theme) throughout the entire cutscene, but in the GameCube the music cuts out for about ten seconds as Rouge begins to read the report before switching to Throw It All Away (Shadow's theme).
The message on the control panel monitor in the ending says "DANGER" in the Dreamcast version. This was changed to "WARNING" in the GameCube version.
When Eggman looks at the control panel monitor of the Eclipse Cannon, the screen is different. Aside from the windows behaving differently, the picture of Gerald Robotnik is easier to see and comes up much earlier on the Dreamcast, giving Eggman time to look at the picture and deduce who it is.
The door to the main room disappears after Rouge finishes Gerald's diary in the GameCube version.
Sonic's thumbs up pose uses his updated model.
There was an error in the Dreamcast version which caused Sonic's right eye to not show up, this was fixed in the GameCube version.
When Sonic and Knuckles encounter the prototype, the slightly transparent clip of Gerald that is made full screen for a moment was mistakenly put over the subtitles on the Dreamcast and were not very easy to see as a result. This was fixed on the GameCube version so that the subtitles are over the clip and a bit easier to see.
The red panel where Knuckles places the Master Emerald in the core flashes in the GameCube version.
Sonic's wave at the end of the game uses the updated model.
The color of Shadow's ring was changed accordingly (from red to yellow) when Sonic gives it to Rouge.