Sonic Generations

"DOUBLE THE SPEED, DOUBLE THE FUN! Celebrate 20 years of Sonic with Sonic Generations."

- SEGA.com

Sonic Generations (ソニック ジェネレーションズ) is a game for Xbox 360, PlayStation 3, Nintendo 3DS and PC via download. The game was made to celebrate the 20th anniversary of the Sonic the Hedgehog series. The Japanese version has different subtitles: White Time and Space (白の時空) for the home consoles, and Blue Adventures (青の冒険) for the 3DS version. This game can be played in 3D on the 3DS and on the console versions also, but a 3DTV as well as a pair of 3D glasses are required for the PS3 and Xbox 360.

Development
Iizuka says the 3DS edition will only feature Sonic's friends "who are integral to the story" - a contrast from the console counterparts. The 3DS version will use some handheld game stages while the console versions will use games from the console main series. "For the PS3 and 360, none of the stages we're selecting are going to be from the handheld." Iizuka said. "However, on 3DS we're looking at picking stages from handheld as well." The 3DS will have minor story changes as well. The writers for the story are credited as Ken Pontac and Warren Graff of Happy Tree Friends fame. They also worked on Sonic Colors and MadWorld. Tetsu Katano, who directed Sonic and the Black Knight and did work on the Adventure series, is directing the 3DS edition. Sonic Team and Dimps are co-developing the 3DS edition.

Console/PC
The story takes place shortly after Sonic's last encounter with Eggman in Sonic Colors. In the past of Green Hill, Classic Sonic is exploring when he hears a noise, he then looks around but dosen't find anything. Suddenly, the Time Eater appears in the sky and he notices it, as the screen goes white. In the present day, Tails and his friends are having a surprise birthday party for Sonic, until the Time Eater appears and sucks all of them back into different periods in Sonic's history. Sonic goes to help but is instead attacked himself; he looks up before he passes out to see that Tails is the only one left struggling to resist the Time Eater's vortex. Sonic wakes from his unconsciousness in a white world with a colorless green hill zone, and wonders what's going on. Sonic first frees Tails when he was in a frozen state. Sonic and Tails then decide on finding their friends.Tails then tells Sonic to go check Chemical Plant out. Sonic quickly sets off, but a few seconds later, Tails sees Classic Sonic and mistakes him for Modern Sonic.

After Sonic brought Chemical Plant back to normal, Tails reaches Sonic and explains how he will never forget the annoying pink acid the place is filled with. Sonic agrees and tells Tails that he feels that he is experiencing Déjà-vu. Meanwhile, Classic Sonic encounters Classic Metal Sonic guarding a Chaos Emerald, and battles him at the bad future of Stardust Speedway, and destroys him. Later, Modern Sonic is in a black and white hall with a glass with Classic Sonic at the other side of the glass. Modern Sonic mistakes it for a mirror, along with mistaking Classic Sonic as his reflection and vice versa. The two started setting their hair and looking at their teeth, concerned about their looks. When the two Sonics touch their bellies, Modern Sonic noticed how his reflection's belly is rounder, and gets the feeling that the reflection is not him. The two then hear Dr. Eggman's voice, with Modern Sonic shouting his name; Classic Sonic looks at his Modern self through the glass and realizes that it was not his reflection the whole time. Classic Sonic runs towards Eggman's voice while Modern Sonic tries to catch up, but instead has the door close on him, resulting in being locked in the room. Sonic was surprised to see his "reflection" running and he wasn't, and realized that his "reflection" was actually Classic Sonic.

Who then finds himself in the Death Egg, Classic Sonic goes exploring but finds himself at a ledge, and falls back with relief. Then the Death Egg Robot appeares in front of him, starting a battle. After the Death Egg battle, he sees the Time Eater kidnapping Classic Dr. Eggman, while the Classic villain ironically cries for help. Modern Sonic then sees his Classic self, and wonders why there is another Sonic. Modern and Classic Tails tell the Sonics that they are traveling through time and space, which is why they are experiencing all of their past encounters, along with seeing Classic Sonic. The two Sonics quickly get along and run towards the other places to bring them back to its color. The two realize that the faster they go through the areas, the more time and color will be restored.

After The Dreamcast Era, Modern Sonic finds Shadow near City Escape. Shadow tells Sonic he doesn't care where he is, he just wants to finish their battle. Sonic accepts and the two battle on in Final Rush. Sonic defeats Shadow with the help of some power cores. Later, while Classic Sonic was in Seaside Hill, Modern Sonic finds himself in a flooded Station Square. the city starts to rumble and Perfect Chaos comes out and starts screaming. He then opens his eyes and spots Sonic, and the battle begins. After the battle, Perfect Chaos drowns. After Perfect Chaos, the gang has a little chat until Time Eater appears leaving 3 more zones in the white limbo, after leaving the third zone, Time Eater spots a colorless Chaos emerald who tries to attack, it but the power Chaos Emerald blocks it off. Classic Sonic finds Silver above Crisis City. Silver is surprised to see Sonic, and thinks he is a faker because hasn't seen him in a long time. Silver challenges him to a battle in Crisis City. Modern Sonic appears, and rushes to the scene of the battle, and joins in.

After restoring every friend and only one more place to bring back, the two Tails realize that the Time Eater dislikes Chaos Emeralds and tell the two Sonics to collect the seven Emeralds. The two Sonics restore Planet Wisp and race each other to the Emerald. Modern Sonic beats Classic Sonic in the race because he's had more experience (using the Sonic Boost in the air). After beating the Egg Dragoon, Classic Sonic gets confused to see Eggman inside of it, as he thought that Eggman got kidnapped. However, the Time Eater comes again and kidnaps Eggman once again, leaving the gang confused.

The gang then chases after the Time Eater and find it to be a supernatural being converted to a machine being piloted by Modern and Classic Dr. Eggman. When asked, Modern Eggman explains that when he was in trapped in space with Orbot and Cubot at the end of Sonic Colors, he found a monster with a unique ability to erase time and space. His plan was to undo all of his past mistakes whilst kidnapping Sonic's friends to use as bait to get Sonic to chase after him. He also had the help of Classic Eggman in order for all of it to work. The monster tries destroying the two Sonics; though they put up a decent fight, it quickly managed to throw them off the ground and crush them with its arm. The two Sonics pass out, but they get support from all of their friends along with Shadow and Silver, allowing the Chaos Emeralds to glow and activate, transforming them into Super Sonics. The two defeat the Eggmans and their monster, and return back to where Sonic had his birthday party.

At the party, Modern Sonic got to enjoy the rest of his chili dog as Classic Sonic and the rest of the gang reappeared, including Shadow and Silver. After a few conversations between the two Sonics and two Tails, Classic Sonic tries out Sonic Boost in the air but slightly fails to keep up. Modern Sonic claps for Classic Sonic, saying that he will get better. Modern Sonic and Tails share a few high-fives and wave good-bye as Classic Sonic and Tails jump back to their time-line.

A post-credits scene shows the two doctors lost in a blank and timeless existence. The two argue as they search for an exit, discussing whether or not they have ever defeated Sonic and contemplating if they should go back and get their teaching degree, as opposed to continuing their misdeeds.

Handheld
The story begins with Classic Sonic in Green Hill. After completing Act 1, a purple vortex appears and surprises Classic Sonic. Then it goes all the way to the present day. Sonic is invited to a party by Tails. However Sonic arrives early. And Tails tells him to wait. Then a vortex sucks Tails in. Sonic jumps in but is "attacked", though he manages to get in anyway. Sonic sees a white world and wonders what's going on. Modern Sonic rescues Tails after restoring Green Hill, and Tails tells him that he sees a big city in nighttime and a giant mushroom, so Sonic decides to go check those places out, being followed by Classic Sonic. After restoring Casino Night, Tails informs Sonic that he feels like he has been there and Sonic mentions that he had a some sort of Déjà-vu of that place too. After restoring all of the zones in the Classic Era, the Boss Gate opens and Sonic enters it. He then sees Classic Sonic through a glass, thinking that it's a mirror. Then, both Sonics hear Eggman's voice, and Classic decides to follow the voice through a portal, but Modern was unable to get there in time. After entering the portal, Classic Sonic meets with Metal Sonic and races him. After winning, Classic Sonic meets with Robotnik on his giant robot, the Big Arm. After the boss fight with the Big Arm, Robotnik is kidnapped by the Time Eater and the 2 Sonics and the 2 Tails meet. Classic Sonic learns the Homing Attack after Modern Sonic used it on some Spinners.

After clearing the Adventure Era (The Dreamcast Era is called this), the Sonics go to the boss gate and Modern Sonic tells Classic Sonic that he's going to take care of it. After beating both Shadow and the Biolizard, Tails does some modifications to Modern Sonic's shoes so he can do the Stomp.

At the DS Era, Sonic meets with Eggman again on his Egg Emperor. After the fight, Eggman is kidnapped by the Time Eater again.

After beating all the levels, the Sonics go to fight the Time Eater who turned out to be some sort of monster being controlled by both Classic and Modern Eggman, and from seeing both Tails defend the Sonics from the monster, the Chaos Emeralds allow the Sonics to go Super.

After defeating the Time Eater, both Sonics and Tails return to the place where the party was going to take place, right after that Sonic starts eating his chilli dog. However, Classic Tails realizes that the vortex to the past was closing, so he and Classic Sonic had to go back. Just before leaving, Classic Sonic shows Modern that he's learning the boost as well. After telling him to have a great future, Modern Sonic says goodbye to Classic Sonic and he, along with Classic Tails, return to the past.

Sonic Boom
A Sonic Generations demo was playable at 2011's E3 Expo, under the name Sonic Boom. It was the first major American Sonic event, being hosted by SEGA, and took place on June 8th, at 6pm PT. At E3, Sonic Generations was playable in both console and handheld versions. Although only Green Hill was playable for the console versions, City Escape was shown; Green Hill was playable, including the boss Big Arm, was playable for the 3DS version. There was also a Birthday Song for Sonic sung at Sonic Boom and the ending of the song, "Happy Birthday Sonic!" will appear in Sonic Generations. This song appeared at the Tokyo Joypolis event and at the Summer of Sonic event in London. It appeared at the Gamescon 2011 event in Germany, and at TGS (Tokyo Game Show) 2011.

Demo Release
The Australian government’s OFLC rated a multi-platform demo release of Sonic Generations, and SEGA formally announced at E3, that they will release a demo for PSN and Xbox Live on Sonic's 20th Anniversary, June 23rd. The demo only contained Green Hill, and only the Classic Sonic playthrough. The demo was only available until July 12th, at which point it was no longer available, including for players who had already downloaded it; the file has essentially locked itself. In the Xbox Live version, one has to be an Xbox Live Gold Member to download the demo. The name of the demo is "Sonic Generations Green Hill Zone Demo #1", indicating that a Modern Sonic demo is on the way. SEGA confirmed on their blog a second demo released in Europe for PSN and Xbox Live on October 18th and was released in North America for PSN on October 25th. The demo contains both classic and modern Sonic playable in Green Hill Zone, and has no time limit.

Gameplay
The game features levels derived from 20 years of Sonic history, ranging from the Classic era, through the Dreamcast era, to the Modern era. There will be a level taken from each other Sonic games to represent the different times. Each level can be played with either Classic Sonic or Modern Sonic, each taking their own routes throughout the level. Classic Sonic's levels are strictly two dimensional side scrolling stages, using classic moves like the Spin Attack and the Spin Dash. Modern Sonic's levels, on the other hand, carry on the modern 2D/3D gameplay of recent titles such as Sonic Unleashed and Sonic Colors, featuring Homing Attacks, Combo Tricks in the air, Drift, the Stomp Attack, Light Speed Dash, and Speed Boosts. There is going to be a new interactive menu that allows for complete immersion into Sonic's universe, as the player completes the game, extras are unlocked such as favorite characters and hidden treasures.

Hub worlds like the ones in Sonic Unleashed have been confirmed in an interview with Takashi Iizuka. He said that the hub world starts out as the white space, but opens up more as the Sonics pass through more levels. The Hub worlds will only be playable in 2D, so they are not free roam like they were in Unleashed. Also, characters rescued in that stage will stand outside the entrance to the stage, and they can be talked to. Also, there is an area above the entrance to the main stage where the player can access extra missions and boss stages. Patrick Riley, the Director of Sega America, has talked about updated gameplay issues.

The speed boost on Green Hill inclines was enhanced and fixed, among other physics issues, a few were noticed when Generations gameplay was first revealed to the world. The handheld version, unlike the console versions, makes the Modern Sonic gameplay similar to Sonic Rush, while also featuring Special Stages based on Sonic Heroes. Some bosses are played as Classic Sonic and some are played as Modern Sonic. This game, like most other Sonic games, features acts, with Act 1 played as Classic Sonic and Act 2 played as Modern Sonic, along with 10 missions per level.

Classic Sonic


Classic Sonic stages consist of him running in a permanent 2-D perspective, platforming all the way towards an end sign post just like in the original games. Patrick Riley referred to Classic Sonic levels as "Momentum-Based Platforming". He can also use the Spin Dash.

The handheld 3DS version uses stereoscopic 3-D to give a sense of depth. Classic Sonic also has an unlockable homing attack. Classic Sonic does not talk at all in the game.

Modern Sonic
Modern Sonic's console stages consist of running extremely fast through the stages while the perspective switches between 2D and 3D such as in his more recent games, Sonic Unleashed (PS3/Xbox 360, daytime levels) and Sonic Colors (Wii version) specifically.

There are also new Combo Tricks, which are performed in the air, and fill up the Boost Gauge. There is a new visual element to all returning levels such as the cave in Green Hill. There's a bit more platforming involved like the sections after the cave in Green Hill. The camera is also immovable unlike how it was in Sonic Unleashed and invisible walls can hinder the exploration aspect.

In the handheld version, Modern Sonic's gameplay is similar to Sonic Rush and Sonic Colors (DS version) and will have the Sonic Boost, the ability to slide under obstacles, jump off walls, and use the Homing Attack. After the Dreamcast Era, Modern Sonic learns the Stomp. Modern Sonic's levels use the 3-D effect of depth on the handheld version more actively, although the console versions are 3D TV compatible.

Genesis/MegaDrive
Sonic the Hedgehog (1991 game) is available to unlock. To play the game, you have to buy the "Sega Genesis/Mega Drive Controller" for 7777 skill points from the Skill Shop.

Profile Card (3DS version only)
The profile card is a feature in the 3DS version. It shows your user name, your rank (such as Novice and Expert), how many years have passed since you became a Sonic fan, your favorite Sonic game, as well as your favorite character, your Mii, and the points it has. On the back (you can turn the card by pressing the R button), it shows the progress you have in the story, how much you have unlocked in the Collection Room, how many missions you have unlocked, how many rings you have collected, your play time, and all of the ranks you have gotten on the levels.

You can also unlock backgrounds for it by leveling up your card. The backgrounds were taken from different Sonic games, including all the ones that are represented in Generations. There are some obscure choices such as Sonic 3D Blast, Sonic Spinball, Sonic the Fighters, Sonic Riders and even Shadow The Hedgehog.

Versus Mode (3DS version)
There is local wireless and Wi-Fi 2-player race mode in the 3DS version of the game. In the multiplayer mode, you can use Download Play to send a signal to another 3DS user, or you can challenge the world by using the Wi-Fi connection. There are also online leaderboards between your races and world-wide races. By playing online races, you can earn points for your profile card, and after playing more online races, you can unlock extra content in the collection room, as well as some of the 100 extra missions.

StreetPass (3DS version)
StreetPass is used to unlock special content and challenges, and is activated when someone with a 3DS passes by someone else with a 3DS. You can also use the Nintendo 3DS "Playcoins" system to buy content such as missions (which cost 5 Playcoins each) in case you are unable to StreetPass (you can also unlock content by playing online). With StreetPass, you can trade your profile card as well as adding 3 missions to exchange with other players. Once you StreetPass somebody, your profile card gets upgraded in various ways.

30-second Trial (Console/PC version)
In this mode you have to get as far as you can in a stage in 30 seconds. You can upload your score online and see who of your friends made it the farthest in one specific level.

Time Attack
In this mode, you can see how fast you can clear a stage, a rival or a boss fight and share your time in online leaderboards. In the 3DS version, all stages can be played for a top time, and 300 Supporter Points (for your profile card) are awarded for each time submitted to the leaderboards. In the 360/PS3 version, Time Attack can only be done online, and only the 18 Main Acts can be played for a top time.

Playable

 * Sonic (Both Classic and Modern)
 * Super Sonic (Both Classic and Modern)

Friends

 * Miles "Tails" Prower (Both Classic and Modern)
 * Knuckles the Echidna (Console/PC version)
 * Amy Rose (Console/PC version)
 * Cream the Rabbit (Console/PC version)
 * Rouge the Bat (Console/PC version)
 * Vector the Crocodile (Console/PC version)
 * Espio the Chameleon (Console/PC version)
 * Charmy Bee (Console/PC version)
 * Blaze the Cat (Console/PC version)
 * Shadow the Hedgehog
 * Silver the Hedgehog

Other

 * Omochao (Optional guide)
 * Dr. Eggman (Both Classic and Modern; arch-rivals of Sonic(s))
 * Cheese the Chao (Follows Cream)
 * Classic Metal Sonic (Boss)
 * Chaos (Boss)
 * Biolizard (Boss in 3DS)
 * Egg Emperor (Boss in 3DS)
 * Chao (They appear in a Speed Highway mission)
 * Animal friends (Flickies and other species must be rescued)
 * Orange Wisp (Console power-up for Modern Sonic)
 * Pink Wisp (Console power-up for Classic Sonic)
 * Red Wisp (3DS power-up for Classic Sonic)
 * Cyan Wisp (3DS power-up for Modern Sonic)

Cameos

 * Fang the Sniper - City Escape (Wanted poster)
 * Bean the Dynamite - City Escape (Wanted poster)
 * Bark the Polar Bear - City Escape (Wanted poster)
 * Mighty the Armadillo - City Escape ("Missing since 1993" poster)
 * Ray the Flying Squirrel - City Escape ("Missing since 1993" poster)
 * Chao - Speed Highway/City Escape/Crisis City/Radical Highway ("Chao in Space" billboard in Speed Highway, "Chao in Space 2" billboard in City Escape, "Chao in Space 3" for Crisis City, and a neon sign for Radical Highway) & Trophy room
 * Perfect Chaos - City Escape ("Chao in Space 2", also a boss)
 * Big the Cat - Casino Night (neon sign) & Trophy room
 * E-123 Omega - Speed Highway (road sign) & Trophy room
 * Death Egg Robot - Speed Highway ("Chao in Space" billboard in Speed Highway)
 * Tikal - Speed Highway ("Chao in Space: The Search For Tikal" billboard)
 * Chip - Speed Highway (road sign) & Trophy room
 * Jet the Hawk - Speed Highway (road sign) & Trophy Room
 * Wave the Swallow - Speed Highway (road sign)
 * Storm the Albatross - Speed Highway (road sign)
 * NiGHTS - Radical Highway (NiGHTS hotel [3DS version only])
 * Orbot & Cubot - (Eggman mentions that he left them in space after the events of Sonic Colors; current status unknown)
 * White Wisps -Planet Wisp (In the beginning of both acts)

Console/PC

 * Motobug - Green Hill
 * Giant Motobug - Green Hill (mission)
 * Chopper - Green Hill/Seaside Hill
 * Mecha Chopper - Green Hill
 * Crabmeat - Green Hill/Planet Wisp
 * Buzz Bomber - Green Hill (with blue and red heads)
 * Giant Buzz Bomber - Green Hill (mission)
 * Spiny - Chemical Plant
 * Grabber - Chemical Plant
 * EggRobo - Sky Sanctuary
 * Cop Speeder - Speed Highway
 * Mono Beetle - City Escape
 * Gun Beetle - City Escape
 * Gun Hunter - City Escape
 * Egg Pawn - Seaside Hill/Planet Wisp
 * Spinner - Seaside Hill/Speed Highway/Planet Wisp
 * Electro Spinner - Seaside Hill/Speed Highway/Planet Wisp
 * Iblis Biter - Crisis City
 * Iblis Taker - Crisis City
 * Iblis Worm - Crisis City
 * Egg Fighter - Rooftop Run
 * Egg Launcher - Rooftop Run
 * Aero Chaser - Rooftop Run
 * Aero-Cannon - Rooftop Run
 * Sandworm - Planet Wisp
 * Buzzer - Planet Wisp

Nintendo 3DS

 * Motobug - Green Hill/Splash Hill
 * Chopper - Green Hill/Splash Hill
 * Crabmeat - Green Hill/Splash Hill
 * Buzz Bomber - Green Hill
 * Newtron - Green Hill/Splash Hill
 * Crawl - Casino Night
 * Butterdroid - Mushroom Hill
 * Mushmeanie - Mushroom Hill
 * Dragonfly - Mushroom Hill/Coral Cave
 * Madmole - Mushroom Hill
 * Baby Kiki - Emerald Coast
 * Rhino-Tank - Emerald Coast
 * Sweeper - Emerald Coast
 * Mono Beetle - Radical Highway
 * Gold Beetle - Radical Highway
 * Gun Hunter - Radical Highway
 * Blue Eagle GUN Plane - Radical Highway
 * Egg Flapper - Water Palace/Power Plant
 * Knight Pawn - Water Palace
 * Klagen - Water Palace/Coral Cave
 * Buzzer - Splash Hill
 * Egg Pawn - Tropical Resort/Power Plant
 * Spinner - Tropical Resort/Power Plant

Rival Bosses

 * Classic Metal Sonic - Stardust Speedway / Casino Night
 * Shadow the Hedgehog - Final Rush / Radical Highway
 * Silver the Hedgehog - Crisis City / Tropical Resort

Console/PC Exclusive

 * Death Egg Robot - Death Egg
 * Perfect Chaos - Station Square
 * Egg Dragoon - Eggmanland

Nintendo 3DS Exclusive

 * Big Arm - Launch Base
 * Biolizard - Cannon's Core
 * Egg Emperor - Final Fortress

Final Boss

 * Time Eater - Center of Time

Items

 * Rings
 * Red Star Rings
 * Item boxes
 * 10 rings
 * Invincibility
 * Elemental Shields (Fire, Lightning, and Bubble)
 * Speed Sneakers
 * Extra Life
 * Skateboard
 * Wisps (Orange and Pink Wisps PS3/360/PC Version) (Cyan and Red Wisps 3DS Version)
 * Chaos Emeralds
 * Wisp Capsules (Modern & Classic)
 * Extra Life (A 3D icon of an extra life appears in the Modern gameplay)
 * Boss Gate Keys
 * Media (Music, Art, and Videos)

Voice Actors
Classic Sonic is silent throughout the game, but still shows his personality through his actions and gestures. Aaron Webber mentioned in an interview, that if anyone were to be Classic Sonic, it would be Jaleel White. Aaron had to make a choice whether Classic Sonic would be voiced by Jaleel White or have no voice at all. Aaron also mentioned that he grew up with the classic cartoons of Sonic like Adventures of Sonic the Hedgehog, and he thought Jaleel White did a fantastic job.

Voice overs exist not only for English and Japanese, but for German, French, Italian, and Spanish.

Soundtrack
The soundtrack for Sonic Generations is called "Sonic Generations Original Soundtrack: Blue Blur" which will include the Soundtrack for both the HD and 3DS versions of Sonic Generations.

The music in the game was remixed by Jun Senoue and Tatsuya Kozaki, with guest remixes done by Tomoya Ohtani, Kenichi Tokoi and Naofumi Hataya (who remixed the classic versions of the Genesis stage themes), among others.


 * Green Hill: Remix of Green Hill Zone from the original Sonic the Hedgehog. The classic remix is similar to the original tune, but with a techno beat. Modern is a much more rock-based theme, with two different versions used dependant on how fast Sonic is going at the time. The hub world music is a violin mix.
 * Chemical Plant: Remix of Chemical Plant Zone from Sonic the Hedgehog 2. The classic remake is almost identical with a techno beat. The modern remix is more of a soft rock.
 * Sky Sanctuary: Remix of Sky Sanctuary Zone from Sonic & Knuckles. The classic remix-as expected-is a nearly the same with a techno beat. The modern remake is a soothing-almost relaxing remix, but still retains a past pace. As with Green Hill, modern Sky Sanctuary has two versions dependant on how fast Sonic is going.
 * Speed Highway: Remix of the first section of Speed Highway from Sonic Adventure. The classic remake by Cash Cash has a techno beat. The modern tune is very similar to the original, but has a heavier use of the guitar.
 * City Escape: Remake of City Escape from Sonic Adventure 2. The classic remix by Cash Cash has a techno beat and traces of the Endless Mine Zone theme. The modern remake is nearly identical, but has some traces of Sonic's theme song "It Doesn't Matter". The song itself is called "Escape from the City".
 * Seaside Hill: Modern is a mixture of a rock remix of both the original Seaside Hill and Ocean Palace, classic only has Seaside Hill.
 * Crisis City: Modern has a violin based remix that is close to the original with a faster beat; Classic has a heavy rock and techno remix of the original but it still sounds similar. This track was remixed by Tomoya Ohtani, who was responsible for the original track.
 * Rooftop Run: Modern is based on the original theme, with some violin modifications and a new piano introduction. Classic has a disco-style remix. This track was remixed by Tomoya Ohtani, who was responsible for the original track.
 * Planet Wisp: Modern has a Drum and Piano remix whilst Classic has a Guitar and Techno Remix. Kenichi Tokoi remixed both the classic and modern tracks.
 * Casino Night: It's a jazz-like remix of Casino Night Zone from Sonic the Hedgehog 2.
 * Mushroom Hill: Classic and Modern (3DS) is based on the theme from Sonic & Knuckles.
 * Emerald Coast: Classic is remix of Azure Blue World. Modern is a remix of "Windy and Ripply."
 * Radical Highway: Classic and Modern have remixes of "Vengeance is Mine," by Cash Cash and Circuit Freq. respectively.
 * Water Palace: Classic has the Water Palace music from the Digital Remakin' Track, while Modern has a remix of "Back 2 Back." by Cash Cash.
 * Tropical Resort: Modern is a faster, guitar rock remix of the original Tropical Resort Act 1 theme, classic is identical to the original Tropical Resort.
 * Hub Worlds: Separate violin renditions of each stage's music are played in the Hub of that Zone.
 * Metal Sonic Rival Battle: Almost the same as the original Stardust Speedway (Bad Future) from the Japanese/PAL soundtrack, with parts of the normal Stardust Speedway theme included. The US version of the theme is a techno remix.
 * Death Egg Robot Battle: Orchestral version of the final boss of Sonic the Hedgehog 2.
 * Shadow Rival Battle: Remix of For True Story by Circuit Freq. from Sonic Adventure 2. Sonic's Attack is a shorter remix of Live and Learn and Shadow's Attack is a shorter remix of All Hail Shadow.
 * Vs. Perfect Chaos: Remix of "Open Your Heart" from Sonic Adventure. It has an added beat and slightly heavier bass. Circuit Freq remixed the track with Jun Senoue providing a new guitar performance.
 * Vs. Perfect Chaos (Pinch): Re-orchestrated version of the music used in the second round of the battle against Perfect Chaos.
 * Silver Rival Battle: Remix of Vs. Character theme from Sonic the Hedgehog (2006).
 * Egg Dragoon Battle: Remix of the Final Battle in Sonic Unleashed.
 * Big Arm Battle: (3DS) Remix of the Final Boss theme for Sonic the Hedgehog 3, rendered by Alex Makhlouf of Cash Cash.
 * VS. Biolizard: Remix of "Supporting Me."
 * Menu: Rendition of the Sonic Heroes Menu Theme.
 * Loading Screen: Remix of the saving center in Eggman's Metropolis from Sonic Chronicles: The Dark Brotherhood.
 * Invincibility: For both Modern and Classic, this is a remix based off the original Sonic the Hedgehog 2 Invincibility theme. The Modern remix is only present in the 3DS version.
 * Speed Shoes: For Classic Sonic only, when the stage's original music is played, the music speeds up. If a different music track is played (such as "Endless Possibility" from Sonic Unleashed or Splash Hill Zone from Sonic the Hedgehog 4: Episode I), the Sonic Adventure (1 & 2) Speed Shoe track plays.﻿
 * Drowning: Orchestral remix based on the drowning theme from Sonic Adventure. Strangely, this is not heard in the Nintendo 3DS version (Water Palace).
 * Time Break: Slower paced remix of Cyber Track from Sonic Advance 3 and also includes parts of the Chaos Control jingle (Boss ver.) from Shadow The Hedgehog.
 * Game Over: Remix of the game over theme from Sonic 3 & Knuckles.
 * Special Stage: (3DS) is a remix of the Special Stage from Sonic Heroes.
 * Super Sonic: Remix of the introduction to "Live and Learn" and the Invincibility theme fromSonic 4.
 * Co-op Mission: Remix of Balloon Park from Sonic 3 & Knuckles multiplayer mode.
 * Race Mission: Pop and techno remix of "Super Sonic Racing" from Sonic R.
 * Skill Shop: Remix of the results screen from Sonic the Hedgehog 2.
 * Collection Room: Violin rendition of "Door into Summer" from Knuckles Chaotix.
 * Media Select: Violin rendition of the data select from Sonic 3 & Knuckles.
 * Network: Remix of the title theme from Sonic Mega Collection.
 * End Medley: Medley of every stage from the game, containing slightly modified versions of the original themes of each stage, similar to "Medley Rush" from Sonic Rush. It starts off and ends like in the ending theme of Sonic the Hedgehog (1991).

Unlockable Music
Music can be unlocked by completing some missions or collecting a number of red star rings. You can view your music by going to the collection room and you can use music for stages. There is a total of 50 unlockable songs in the Console and PC versions, which are:
 * "Green Hill Zone (Original)" (Sonic the Hedgehog)
 * "Marble Zone" (Sonic the Hedgehog)
 * "Star Light Zone" (Sonic the Hedgehog)
 * "Emerald Hill Zone" (Sonic the Hedgehog 2)
 * "Chemical Plant Zone (Original)" (Sonic the Hedgehog 2)
 * "Special Stage" (Sonic the Hedgehog 2)
 * "Angel Island Zone" (Sonic the Hedgehog 3)
 * "Hydro City Zone" (Sonic the Hedgehog 3)
 * "Marble Garden Zone" (Sonic the Hedgehog 3)
 * "Mushroom Hill" (Sonic and Knuckles)
 * "Flying Battery Zone" (Sonic and Knuckles)
 * "Death Egg Zone" (Sonic and Knuckles)
 * "Open Your Heart" (Sonic Adventure)
 * "It Doesn't Matter" (Sonic Adventure)
 * "Emerald Coast" (Sonic Adventure)
 * "Metal Harbor" (Sonic Adventure 2)
 * "Live & Learn" (Sonic Adventure 2)
 * "Green Forest" (Sonic Adventure 2)
 * "Special Stage - Bonus Challenge" (Sonic Heroes)
 * "Sonic Heroes" (Sonic Heroes)
 * "What I'm Made Of..." (Sonic Heroes)
 * "His World" (Sonic 06)
 * "Wave Ocean" (Sonic 06)
 * "Kingdom Valley" (Sonic 06)
 * "Endless Possibility" (Sonic Unleashed)
 * "Windmill Isle - Day" (Sonic Unleashed)
 * "Savannah Citadel - Day" (Sonic Unleashed)
 * "Reach for the Stars" (Sonic Colors)
 * "Tropical Resort" (Sonic Colors)
 * "Sweet Mountain" (Sonic Colors)
 * "Toxic Caves" (Sonic Spinball)
 * "Palmtree Panic - Present (Japanese Soundtrack)" (Sonic CD)
 * "Sonic Boom" (Sonic CD)
 * "Stardust Speedway" (Sonic CD)
 * "Diamond Dust Zone" (Sonic 3D Blast)
 * "Super Sonic Racing" (Sonic R)
 * "Neo Green Hill Zone" (Sonic Advance)
 * "Leaf Forest" (Sonic Advance 2)
 * "Route 99" (Sonic Advance 3)
 * "Right There, Ride On" (Sonic Rush)
 * "A New Venture " (Sonic Rush Adventure)
 * "High Flying Groove" (Sonic Riders)
 * "Un-Gravitify" (Sonic Riders: Zero Gravity)
 * "Free" (Sonic Free Riders)
 * "Quick Trip To Paradise" (Sonic Rivals)
 * "Race To Win" (Sonic Rivals 2)
 * "I Am... All of Me" (Shadow the Hedghog)
 * "Let the Speed Mend It" (Sonic and the Secret Rings)
 * "Knight of the Wind" (Sonic and the Black Knight)
 * "Splash Hill Zone " (Sonic the Hedgehog 4)

The 3DS version also has 51 unlockable songs, which can be heard in the collection room (even when the 3DS is closed with headphones connected to it,working like a MP3 player) This songs are unlockable rewards for completing the missions:
 * "Green Hill Zone" (Sonic the Hedgehog)
 * "Marble Zone" (Sonic the Hedgehog)
 * "Star Light Zone" (Sonic the Hedgehog)
 * "Emerald Hill Zone" (Sonic the Hedgehog 2)
 * "Chemical Plant Zone (Original)" (Sonic the Hedgehog 2)
 * "Special Stage" (Sonic the Hedgehog 2)
 * "Angel Island Zone" (Sonic the Hedgehog 3)
 * "Hydro City Zone" (Sonic the Hedgehog 3)
 * "Marble Garden Zone" (Sonic the Hedgehog 3)
 * "Mushroom Hill" (Sonic and Knuckles)
 * "Flying Battery Zone" (Sonic and Knuckles)
 * "Death Egg Zone" (Sonic and Knuckles)
 * "Open Your Heart" (Sonic Adventure)
 * "Believe In Myself" (Theme of Tails) (Sonic Adventure)
 * "My Sweet Passion" (Theme of Amy) (Sonic Adventure)
 * "Live and Learn" (Sonic Adventure 2)
 * "Unknown From M.E." (Theme of Knuckles) (Sonic Adventure 2)
 * "Throw It All Away" (Theme of Shadow) (Sonic Adventure 2)
 * "Sonic Heroes" (Sonic Heroes)
 * "What I'm Made Of" (Sonic Heroes)
 * "Seaside Hill" (Sonic Heroes)
 * "Right There, Ride On" (Sonic Rush)
 * "Jeh Jeh Rocket" (Sonic Rush)
 * "Vela Nova" (Sonic Rush)
 * "A New Venture" (Sonic Rush Adventure)
 * "Blizzard Peaks" (Act 1/Act 2 mix) (Sonic Rush Adventure)
 * "Sky Babylon" (Act 1/Act 2 mix) (Sonic Rush Adventure)
 * "Reach for the Stars" (Sonic Colors)
 * "Aquarium Park" (Act 1) (Sonic Colors)
 * "Starlight Carnival" (Act 1) (Sonic Colors)
 * "Toxic Caves" (Sonic Spinball)
 * "Palmtree Panic" (Sonic CD)
 * "Sonic Boom" (Sonic CD)
 * "Door into Summer" (Knuckles Chaotix)
 * "Diamond Dust" (Sonic 3D Blast)
 * "Super Sonic Racing" (Sonic R)
 * "Sonic Stage" (Emerald Beach) (Sonic Battle)
 * "Neo Green Hill" (Sonic Advance)
 * "Leaf Forest" (Sonic Advance 2)
 * "Route 99" (Sonic Advance 3)
 * "Quick Trip to Paradise" (Sonic Rivals)
 * "Race to Win" (Sonic Rivals 2)
 * "His World" (Sonic the Hedgehog) (2006)
 * "Endless Possibility" (Sonic Unleashed)
 * "High Flying Groove" (Theme of Heroes) (Sonic Riders)
 * "Un-Gravitify" (Sonic Riders: Zero Gravity)
 * "Free" (Sonic Free Riders)
 * "Let the Speed Mend It" (Sonic and the Secret Rings)
 * "Knight of the Wind" (Sonic and the Black Knight)
 * "Splash Hill Act 1" (Original) (Sonic the Hedgehog 4)
 * "Splash Hill Act 3" (Original) (Sonic the Hedgehog 4)

Skills
Skills are items both Sonics' can use in acts and some missions. They can be unlocked by doing a certain mission, buying them at the skills shop, or collecting five star rings in an act. Here are the skills they can get, along with their skill point cost:

Classic Sonic

 * Aqua Shield - Enables Bound Jumps and eliminates the need to get air. (70 SP; can be used 1 time per life)
 * Boardmaster - Hop on a skateboard whenever you want. (70 SP; can be used 1 time per life)
 * Breath Holder - Stay underwater longer. (20 SP)
 * Flame Shield - A Shield that enables midair dashes. (70 SP; can be used 1 time per life)
 * Hercules Muscles - Push movable objects faster. (10 SP)
 * Homing Attack - Enables the use of Homing Attacks. (100 SP)
 * Invincible Start - Start the stage with temporary invincibility. (40 SP)
 * Long Spin Dash - Your Spin Dash will carry you further. (30 SP)
 * Power Sneakers - Run faster, plain and simple. (60 SP; can be used 2 times per life)
 * Ring Time - Turns enemies into Rings for a short time. (60 SP; can be used 5 times per life)
 * Shield - A Shield protects you from a single hit. (60 SP; can be used 2 times per life)
 * Thunder Shield - Enables double-jumping. (70 SP; can be used 1 time per life)
 * Treasure Scanner - Allows you to see hidden items and Springs. (40 SP)
 * Twin Spin Attack - Allows you to attack in mid-jump. (30 SP)

Modern Sonic

 * Acceleration - Increases speed when starting to run. (10 SP)
 * Auto-Gauge - Boost Gauge fills automatically over time. (30 SP)
 * Blast Off - Press a button when "GO!" appears for a free Boost. (10 SP)
 * Boost Gauge Up - This extends the length of your Boost Gauge. (60 SP)
 * Direct Jump - Increase the speed of your Wall Jumps. (30 SP)
 * Endless Boost - The Boost Gauge stays full but you can't get Rings. (70 SP)
 * Gauge Rebooter - Begin with a full Boost Gauge upon restart. (30 SP)
 * Power Stomp - Creates a shockwave when Stomp is used. (30 SP)
 * Quick Slide - Enables Quick Step when on a skateboard. (30 SP)
 * Ring Energy Bonus - Collecting Rings fills the gauge faster. (40 SP)
 * Serial Homing - Perform sequential Homing Attacks faster. (40 SP)
 * Smasher Bonus - Breaking enemies, etc. fills Boost Gauge. (30 SP)
 * Speed Up - Increase Sonic's speed. (20 SP)
 * Trick Mastery - Perform Tricks faster. (60 SP)

Both

 * 10-Second Rings - Dropped Rings take 10 seconds to disappear. (30 SP)
 * Athleticism - Lost less speed moving uphill and in water. (20 SP)
 * Infinite Continues - Get infinite continues on the Sega Genesis!
 * Last Chance - Get an extra life when you're out of lives. (50 SP)
 * Life +1 - This gives you one extra life. (Can be purchased as many times as wanted/needed)
 * Power Brake - Stop on a dime no matter how fast you run. (10 SP)
 * Safety Net - Begin with 10 Rings after a restart. (40 SP)
 * Sega Genesis/Mega Drive Controller - Play "Sonic the Hedgehog" on the Sega Genesis/Mega Drive!
 * Super Sonic - Collect 50 Rings to become Super Sonic. (100 SP; can be used indefinitely per life)
 * Sure-Footed - Land on your feet after getting damaged. (20 SP)
 * Time Brake - Slows down time temporarily. (80 SP; can be used indefinitely per life)

Secret Statue Room/Models
In the console/PC version of the game, inside the media room, there lies a secret area where you can collect many characters with various codes, even characters who didn't appear in the game otherwise. In the 3DS version's collection room, there's a section called "Models" which is basically the same thing as the statue room. However, the statues are unlocked by doing the missions, rather than using special codes.
 * Sonic the Hedgehog
 * Classic Sonic
 * Miles "Tails" Prower
 * Classic Tails
 * Amy Rose
 * Knuckles the Echidna
 * Cream the Rabbit & Cheese
 * Rouge the Bat
 * Espio the Chameleon
 * Blaze the Cat
 * Vector the Crocodile
 * Charmy Bee
 * Chao
 * Omochao
 * Dr. Eggman
 * Classic Eggman
 * Classic Metal Sonic
 * Shadow the Hedgehog
 * Silver the Hedgehog
 * Big the Cat
 * E-123 Omega
 * Jet the Hawk
 * Hero Chao
 * Dark Chao
 * Chip
 * Moto Bug
 * Buzz Bomber
 * Crabmeat
 * Chopper
 * Grabber
 * Spiny
 * Egg Robo
 * Cop Speeder
 * Spinner
 * G.U.N. Hunter
 * Mono Beetle
 * Egg Pawn
 * Iblis Biter
 * Iblis Taker
 * Iblis Worm
 * Egg Fighter
 * Egg Launcher
 * Egg-Cannon
 * Egg Chaser
 * Sandworm
 * Classic Spring
 * Modern Spring
 * Item Box
 * Capsule
 * Goal Plate
 * Goal Ring
 * Ring
 * Chaos Emeralds
 * Launcher
 * Animal Friends

The models are:
 * Sonic the Hedgehog
 * Dr. Eggman
 * Miles "Tails" Prower
 * Amy Rose
 * Metal Sonic
 * Knuckles the Echidna
 * Big the Cat
 * Shadow the Hedgehog
 * Rouge the Bat
 * Cream the Rabbit & Cheese
 * E-123 Omega
 * Silver the Hedgehog
 * Orbot & Cubot
 * Chaos Emeralds
 * Big Arm
 * Biolizard
 * Egg Emperor
 * Time Eater

Stages
Stages are divided into 3 eras: the Mega Drive/Genesis era, the Dreamcast era, and the current, Modern era. Levels and Bosses are different between the console and 3DS versions with the exception of Green Hill.

Classic Era

 * Green Hill (Sonic the Hedgehog)
 * Chemical Plant (Sonic the Hedgehog 2)
 * Sky Sanctuary (Sonic the Hedgehog 3 & Knuckles)

Dreamcast Era

 * Speed Highway (Sonic Adventure)
 * City Escape (Sonic Adventure 2)
 * Seaside Hill  (Sonic Heroes)

Modern Era

 * Crisis City (Sonic the Hedgehog (2006))
 * Rooftop Run (Sonic Unleashed)
 * Planet Wisp (Sonic Colors)

Bosses

 * Classic Metal Sonic, Stardust Speedway (Sonic CD)
 * Death Egg Robot, Death Egg (Sonic the Hedgehog 2)
 * Perfect Chaos, Station Square (Sonic Adventure)
 * Shadow the Hedgehog, Final Rush (Sonic Adventure 2)
 * Silver the Hedgehog, Crisis City (Sonic the Hedgehog 2006)
 * Egg Dragoon, Eggmanland (Sonic Unleashed)
 * Time Eater, Center of Time (Sonic Generations)

3DS
Unlike the console versions, after you beat Green Hill in the first era, you are free to choose which zone and act of the era you want to do first.

Classic Era

 * Green Hill (Sonic 1)
 * Casino Night (Sonic 2)
 * Mushroom Hill (Sonic 3 &amp; Knuckles)

Dreamcast Era

 * Emerald Coast (Sonic Adventure)
 * Radical Highway (Sonic Adventure 2)

Modern Era

 * Water Palace (Sonic Rush)
 * Tropical Resort (Sonic Colors)

Bosses

 * Classic Metal Sonic, Casino Night (Sonic 2)
 * Big Arm, Launch Base (Sonic 3 & Knuckles)
 * Shadow the Hedgehog, Radical Highway (Sonic Adventure 2)
 * Biolizard, Cannon's Core (Sonic Adventure 2)
 * Silver the Hedgehog, Tropical Resort (Sonic Colors)
 * Egg Emperor, Final Fortress (Sonic Heroes)
 * Time Eater, Center of Time (Sonic Generations)

Special Stages
Special Stages will appear in the 3DS version. The style of the play is akin to the Special Stages in Sonic Heroes. A Chaos Emerald will be achieved if the stage is completed. Super Sonic will be exclusive to the final boss. It was called "Unlockable Special Stages" during SEGA's press conference regarding the 3DS version of the game. For the console versions, you collect the Chaos Emeralds by defeating the 3 bosses and 3 rivals, plus one more that is automatically given when both Acts are cleared on "Planet Wisp".

Reception
Since its release, Sonic Generations has received generally positive reviews, with most reviewers praising the different game styles and feel of nostalgia, but criticizing the over-responsive controls and extra levels with Sonic's friends. IGN gave the game an 8.5 out of 10, praising the overall gameplay and the level design, whilst disliking the few boss battles and the occasionally clunky controls. They also criticized the storyline for being superfluous, although they praised it for paying "homage to Sonic games of the past." Destructoid's Jim Sterling gave it an 8 out of 10, noting that "If Sonic Team can keep this up, then the blue blur will most definitely be back on top." Computer and Video Games gave it a 7.5/10, commenting that "the balance of intensity and fairness is just about spot on" from a design perspective, but arguing that the game occasionally moved too fast for the player to respond well to obstacles and that "the framerate dips dramatically" in the 2D sections, which can be jarring. The review added that "it's a shock how much easier on the eyes" the original Sonic the Hedgehog is, "with its thumping great pixels and velvety-smooth parallax scrolling," and that the 3D sections run much smoother because "there's so much action going on in every direction that jerkiness on a single plane is far less noticeable." Finally, the review criticized the addition of characters like Amy, Knuckles, and Cream for side missions while praising "the level of effort and creativity" that went into the "immense" levels. 1UP gave the game a "B" score, writing that "Generations' liberal borrowing from Nintendo's school of game design stands as one of Sega's smartest decisions in years," its "challenges feature an amazing amount of variation" and concluding that it "has quite an array of impressive and fun-to-play levels, full of interesting set pieces that draw from Sonic’s past." Their only complaints were that many levels featured on-rails or auto-pilot sequences "which can be frustrating and often jarring when control is suddenly thrust back into your hands" and that the warning signs which prepare the player for pitfalls are "easy to miss." PlayStation Official Magazine gave it an 8/10, stating that "each act is a masterpiece of platform game design... it's sprawling and focused all at once, every pixel placed with the express purpose of making you go really, really fast" and noting that the difficulty was so perfectly balanced that "no matter how many times I missed a jump or drowned Sonic (I remain convinced that hedgehogs can swim), I blamed my slow thumbs rather than the game." However, the review felt that "the more stationary challenges – digging for medals with Knuckles, for example – are tedious." Nintendo Power gave the 3DS version of Sonic Generations a 8.0, saying that it should please any Sonic fan but criticized that the game can be finished in an afternoon. Unlike Sonic Colors, the game did not get many awards in the first year having only one of Gamezone's Best Presentation award. It's lowest rating was given by EDGE giving it 5/10.

Gallery

 * For more: Sonic Generations/Gallery.

Videos
Video:Sonic Generations - Teaser Trailer HD|Sonic Generations Teaser Trailer Video:Sonic Generations Gameplay Trailer|Official Green Hill gameplay trailer Video:Sonic Generations E3 2011 Trailer CITY ESCAPE|City Escape Trailer Video:Sonic Generations Japanese City Escape trailer with Modern Music!|Japanese City Escape trailer with Modern Escape from the City Video:Sonic Generations: Two Sonics Trailer|Two Sonics trailer Video:Sonic Generations: New Levels Trailer|Classic Era Trailer Video:Sonic Generations - Dreamcast Era Trailer|Dreamcast Era Trailer Video:Sonic GenerationsModern gen Era Trailer|Modern Era Trailer Video:Sonic Generations: All Bosses Trailer|Rivals and Bosses Trailer Video:Sonic Generations: 3DS Gameplay Trailer|3DS Version Trailer Video:Sonic Generations Extended gameplay footage|Modern and Classic Green Hill Zone gameplay Video:Sonic Generations HD Gameplay (Chemical Plant Zone and City Escape)|Chemical Plant and City Escape Modern and Classic Japanese Video:Sonic Generations - Classic Era Gameplay|Classic Era gameplay and Amy. Video:Sonic Generations - Hub World|Hub World Video:Sonic Generations 3DS Gameplay: Comic-Con|Sonic Generations 3DS Comic-Con Gameplay Video:Sonic Generations US Commercial |TV Advert Video:Sonic Generations - Launch Trailer|Launch trailer Video:Sonic Generations: NEW Japanese Commercial Trailer|Sonic Generations Japanese Commercial Video:Sonic Generations - 3DS Launch Trailer|Sonic Generations 3DS Launch Trailer

Merchandise
The game had two newly revealed action figures at Comic-Con 2011. Now early on Nintendo has released these official new Sonic Generations shirts to remark the 20th birthday for a kicking price of $82.00 each.

Jazwares has also released a line of Generations themed toys, from a character with an iconic badnik with a picture of a stage to giant stuffed animals.

Adaptations
Archie Comics produced a video game tie-in for Sonic Generations in Sonic The Hedgehog Issue 230.

A short manga for Sonic Generations was released in Japan. It has been presented in a similar format as to the Sonic Unleashed manga and Sonic Colors manga.

Trivia

 * This is the first Sonic game to have stereoscopic 3D capability.
 * Some of the artworks are poses from past video games in the series.
 * This is the first game where Classic Sonic, Classic Tails, Classic Metal Sonic, and Classic Dr. Robotnik are rendered in CGI.
 * Oddly enough, Amy, Knuckles, and the modern-day Team Chaotix don't have their Classic forms seen in the game. This could be due to not wanting too many Classic characters, and the fact that the Chaotix's Classic forms never appeared in a main-series Sonic title. It can also be noted that a concept of Classic Amy is unlockable.
 * Tails, Knuckles, and Amy's VS. missions are races against Sonic. Coincidentally, they were all playable characters in the racing game Sonic R.
 * Knuckles, Rouge, Espio And Blaze are the only characters that are saved and appear in a stage of that game, with Knuckles in Sky Sanctuary (S3&K), Rouge in City Escape (Sonic Adventure 2), Espio in Seaside Hill (Sonic Heroes) and Blaze in Crisis City (Sonic the Hedgehog 2006).
 * Tails is the only character who races against Modern Sonic. Knuckles and Amy race against Classic Sonic.
 * When racing against Tails and Knuckles a remix of Super Sonic Racing from Sonic R plays. When racing against Amy though, a remix of Emerald Beach from Sonic Battle plays because the race against her is more like a battle with physical contact and attacking occurring in the race.
 * Within the remix of Super Sonic Racing, are segments from commercials for the SEGA Saturn.
 * Jun Senoue mixed the tracks for this game. The music lso speeds up and slightly changes when Modern Sonic uses his boost, but only in Green Hill and Sky Sanctuary.
 * This is the third 3D sonic game not to use the main theme song (or even a remix) for the final boss. The other two being Sonic Heroes and Sonic and the Black Knight.
 * The Classic version of City Escape's theme has a clip of the Endless Mine theme from the multiplayer mode of Sonic the Hedgehog 3.
 * If noticed, in the cutscene before the player faces Time Eater, Classic Sonic does a homing attack.
 * If noticed, Classic Tails's artwork seems to have '"buckles" under his gloves (above his shoe)
 * Like Sonic Unleashed (Wii/PS2), when using the boost while on a Dash Panel, Sonic uses a Spin Dash.
 * The E3 demo, Sonic Boom, is named after the opening theme in the US version of Sonic CD. Crush 40 and Cash Cash performed a remix of this song at Sonic Boom. The original song can also be unlocked in the game and be heard on any stage if the player chooses to change the music for any of the stages.
 * In City Escape, Fang, Bean, Bark can be seen in "wanted" posters, while Mighty and Ray can be seen on a "missing" poster.
 * Like the street signs in Empire City from Sonic Unleashed, City Escape has various buildings named after characters, such as Tails' Pizza, Coffee Blaze, Amy's Market and Vector's Daily.
 * At one point in Green Hill Zone, Modern Sonic is being chased by a giant Chopper, clearly a reference to when he was chased by a whale in both Sonic Adventure and Sonic The Hedgehog (2006).
 * When doing a finish to one of his mid-air Combo Tricks after going through a rainbow-colored hoop or a special dash panel ramp, Modern Sonic does the same widely recognizable pose as he does on the cover for Sonic Adventure.
 * The first 2 gameplay trailers featured an instrumental version of famous songs:
 * Tenderoni by Kele Okereke (Green Hill).
 * Na Na Na by My Chemical Romance (City Escape).
 * Takashi Iizuka revealed that the reason Sonic Generations is coming to the 3DS is because the Wii isn't a good fit for the game, since the primary goal for the console versions is to re-imagine classic stages in vivid, HD graphics. So they decided that, for the Nintendo audience, it would come to the 3DS.
 * This is the first time Modern Sonic gets Boost Energy from both Rings and Enemy Power in a handheld console
 * A Deleted CGI Scene shows modern and classic Sonic running through Rooftop Run, Destroying EGG FIGHTERS,Boosting and Spin Attacking then meeting up with the two Tails at the end near Big Ben. Some of these parts could be seen in the Two Sonic's Trailer but the full video was not to be put in the game.
 * In this game, Classic Sonic has various waiting animations. One looks similar to Sonic 2, one looks similar to Sonic 3 and one looks similar to Sonic 3D Blast.
 * Red Rings are in the game, but they have been renamed as "Red Star Rings."
 * This game has been in development since Sonic Unleashed was released.
 * If noticed, the PS3/X360 versions have a white colored design on top and bottom, where as the 3DS version has a replacement for blue, this is reference to the consoles and handheld's version's Japanese name, White Time and Space (PS3/360) and Blue Adventures (3DS).
 * Some of the stages in demos of the 3DS version have been presented with placeholder music. For example, the Big Arm boss fight used Doomsday Zone's music in the E3 2011 demo, but was changed to the final boss theme of Sonic 3 in the Gamescom 2011's demo.
 * If noticed, when watching movies in the Collection Room, Sonic sits down and watches a TV screen, as if he's watching the movie with you.
 * This is the first main series Sonic game on the PS3 to have hidden trophies.
 * This is the first main series Sonic game on the 360 to have hidden achievements.
 * In the Xbox 360 version of the game, the Statue Room can be accessed by entering the Collection Room and holding down the "Back" button, and the select button in the PS3 version.
 * In this game, Sonic, Tails and Dr. Eggman are the only characters with a Classic and Modern form of themselves (Metal Sonic appears only in his Classic self).
 * The rivals appeared as playable characters in Sonic Rivals.
 * Knuckles is the only rival from Sonic Rivals that is a friend in Sonic Generations as the others are all bosses.
 * In this game, the countdown to drowning starts at 4 instead of 5 although a different tone is played before the countdown starts.
 * On the case cover of the Xbox 360/PS3 version, Modern Sonic's run looks similar to the one on the case cover of Sonic the Hedgehog (2006) which was also released on the 360 and PS3 consoles. On the 3DS one, Modern Sonic looks similar to the one on the case of Sonic Classic Collection, which was released on the DS.
 * This game on regards to Speed Highway for both Classic and Modern Sonic does not include the At Dawn Section from Sonic Adventure and Sonic Adventure DX for unknown reasons, Modern Sonic after coming down from the roof does not go out to daylight but nighttime.
 * Crisis City appears in this game, despite the ending to Sonic 2006 erasing the timeline. Blaze also comments on how she thought she'd never see Crisis City again. This has led to questioning as to how she remembers the location.
 * The Dreamcast Era is the only era in which Dr. Eggman is not a boss.
 * In the E3 demo of Green Hill Act 2 (when the game was in early development), at the beginning of the stage, Sonic said "Ready...Go!", while in the last Demo, he doesn't.
 * When Classic Sonic runs, a blur effect is set in the background.
 * If a 10 Rings box is destroyed, the sound when you got a Ring sounds ten times instead of one.
 * Although no levels from Sonic & the Secret Rings are returning, Sonic makes reference to the events of the game during the second cutscene when he reunites with Tails. "No stranger than rescuing genies from magic books,..."
 * In a cutscene that plays after Modern Sonic finishes Chemical Plant, Tails makes an obvious joke about drowning in Sonic 2's Chemical Plant Act 2, with the exact line being, "This Chemical Plant feels familiar...I'd never forget a smell like this. And that pink water makes me really nervous for some reason."
 * This game follows the events of Sonic Colors according to Dr. Eggman's plan in this game.
 * After Sonic saves Tails, he makes a reference, saying that the stage was "awfully familiar", followed by Tails saying that he doesn't recognize the stage at all. Most likely referencing the fact that Green Hill Zone is a Sonic 1 stage, and Tails was introduced in Sonic 2. Yet in Sonic Chronicles, Tails recognizes Green Hill Zone.
 * This is the second 3D Sonic game where Eggman is the final boss.
 * A floating pot-like enemy from Sonic Colors from various levels, including Planet Wisp, returns in a mission that takes place on that location. This is the first time its English name was revealed, the Sprinkler.
 * Out of all 9 main stages, 3 of the stages are based on the first levels of their respective games (Green Hill Zone, City Escape and Seaside Hill). The 3DS Version has Green Hill, Emerald Coast and Tropical Resort (Mushroom Hill is technically a first stage as well though not in the complete Sonic 3 and Knuckles). To a lesser extent, Crisis City is also considered a starting level (but in the case of Silver, and not Sonic).
 * There are also plays on numbers. Chemical Plant is the second level of the Classic Era (which is taken from Sonic the Hedgehog 2), as well as being the second level overall in Generations. It can also be noted that while Amy never appeared in Sonic 2, she was the second friend Sonic made in the main series. Crisis City, Rooftop Run, and Planet Wisp (depends on the player's choice) are all the fourth stages of their respective games (and coincidentally, all are in the Modern Era).
 * This is the second main 3D game to have someone call Dr. Eggman the name "Dr. Robotnik", the first being Sonic Adventure.
 * Chemical Plant is the only main stage not shown in the Launch Trailer.
 * If noticed, Classic Metal Sonic's pose is similar to Shadow's.
 * In various points of Crisis City, an ad for "Chao in Space III" can be seen.
 * In various points of Radical Highway (modern), signs that say "Time Eater" can be seen.
 * Sonic Generations is the sixth Sonic game to use Time Travel as a theme. The five others are Sonic CD, Sonic Adventure, Sonic the Hedgehog (2006), Sonic Rivals, and Sonic Rivals 2.
 * In the cutscene after the final boss, Classic Sonic attempts to use a Sonic Boost but fails.
 * In both versions of the game, Classic Sonic has the ability to perform the Homing Attack. In the console versions, it is a skill purchased in the Skill Shop (the last one, and it uses all skill points). In the 3DS version, it is learned permanently after the battle with Big Arm, just before the Dreamcast era.
 * This is the second 3D Sonic Game where players start a new game and taken to the first stage, rather than showing the cutscene first. The other being Sonic Colors.
 * Despite the fact that they never appear in the game itself (with the exception of cameos) Jet the Hawk, E-123 Omega, Chip, and Big the Cat all have trophies in the secret trophy room.
 * If noticed, Classic Tails just appears out of thin air after the boss battle with the Death Egg Robot. Takashi Iizuka said that their was going to be an explanation but it never got worked into the game's story, and he wanted to leave it open to the fan's opinion.
 * "History of the 1st Stage: White Edition" and "History of the 1st Stage: Blue Edition" are the Japanese Pre-order bonuses for the HD and 3DS versions respectively, not the soundtrack as originally thought. They are both disks with separate soundtracks that consist of music from the first stage of the franchise.
 * One of Classic Sonic's poses bears a resemblance to Modern Sonic's Super Smash Bros. Brawl artwork.
 * The only main series past games that are not referenced are Shadow the Hedgehog and Sonic the Hedgehog 4, however Super Sonic's theme is the Invincibility song from Sonic 4 and one of the song's played when fighting Shadow is "All Hail Shadow" from Shadow the Hedgehog. Both games also feature an unlockable song (Splash Hill Zone - Act 1 from Sonic 4, and I Am... All Of Me from Shadow the Hedgehog).
 * Takashi Iizuka said that three original taglines for the game were "Blast with the past," "Déjà Blue," and "A speedy trip down memory lane."
 * All the rival bosses are hedgehogs, more or less.
 * While the PS3/360/PC version considers Sonic Heroes as part of the Dreamcast Era, the 3DS version considers it part of the Modern Era.
 * In both versions, the bosses of the eras are all final bosses of a story. The only exceptions are the Biolizard, which had the Finalhazard come after it in Sonic Adventure 2, and the Egg Dragoon, which had Perfect Dark Gaia come after it in Sonic Unleashed.
 * With the exception of Egg Dragoon, all of the bosses in the console/PC version can only take half the amount of hits the 3DS version's bosses can. (4 in the console/PC version, 8 in the 3DS version). However, the console bosses generally have more elaborate attack patterns, and the process of landing a hit is usually longer (ex. platforming mini-courses for Perfect Chaos, but traditional circular arena for Biolizard).
 * The difficulty has increased or decreased depending on the placement of the level when compared to the original level. For example, Rooftop Run is significantly harder than the original version. It can also be said that Planet Wisp is just as hard as the original version (which may be the reason it was included). Tropical Resort was also made harder, with new obstacles such as laser gates and falling meteorites.
 * While the console/PC version uses the shields (Standard, Flame, Thunder, and Bubble) as skills, the 3DS version has them hidden through the levels, resembling the original games. However, only the normal and electric shields appear in the 3DS version (like in previous handheld titles) while in the console/PC version all of the shields appear.
 * When playing the original Sonic the Hedgehog on the Sega Genesis, a top score and top time can be recorded. However, the player must finish the game to save said data.
 * In the 3DS version, when Modern Sonic is running over water in Water Palace without boosting, he'll do the surfing animation from Sonic Unleashed (Wii/PS2).
 * The trailers show cutscenes that never appeared in the actual game, aside from the cutscene that is shown after the title screen pops up.
 * In the console and PC versions, when Classic Sonic gets an invincibility, the music that plays is always the classic remix. However in the 3DS version, the remix that plays depends on the era where Classic got the invincibility (Classic remix in the Classic Era, Modern remix in the Dreamcast and Modern Eras).
 * In the Nintendo 3DS version, Modern Sonic can also find invincibility monitors scattered around his stage. The modern remix is played.
 * Strangely enough, the modern invincibility remix is unused in the Console/PC versions, as those versions lack powerups for Modern Sonic at all.
 * In the Console and PC versions, the Classic Era is the only era without a city level while in the 3DS version the Modern Era is the one without a city level.
 * Despite being rated E by ESRB and 7 by PEGI, this game uses the uncensored version of "His World".
 * In the Console/PC versions of this game, if you stand next to the levels in the hub world, you'll hear a remix of the song in the level. Usually it is an Orchestral remix, using a chello or trombone as the melody, but sometimes it can be Rock music (Like Speed Highway) the music played when next to the Egg Dragoon is a remix of "E.G.G.M.A.N" erasing the lyrics, and when next to the Time Eater boss, no music is played. When next to Shadow, a remix of Shadow's SA2 theme is played, and when next to Silver, a remix of "Dreams of Absolution" is played.
 * In some of the Modern/Classic Missions in Sky Sanctuary, a black variant of the Eggrobo can be seen. This version fires rockets from it's back/arms, similar to the Egg Launcher from The Rooftop Run stage.
 * In the 3DS version, Sonic (after defeating Biolizard) states that it was easy because he already beat Biolizard once. However, he only fought it as the Finalhazard. Shadow fought Biolizard in its first form.
 * Although a stage in the 3DS version, Sonic never went to Radical Highway. Instead, Shadow did.
 * In the Hub-World, Sky Sanctuary has trees with grapes in them. In the manual of Sonic & Knuckles its mentioned that Knuckles's favorite food is grapes, and Sky Sanctuary is also where you save Knuckles in Sonic Generations.
 * There are unused clips of Modern Sonic and Classic Sonic dancing.
 * When you S rank on one of the levels or bosses in the Console/PC version, the text color of the title of it turns Golden.
 * In the secret statue room of the Console/PC version of this game, most of the poses from the character statues come from game artwork in the past, mainly, Sonic Channel.
 * In the Console/PC version, the unlockable music list has slight remixes of the the Classic songs (Mainly Sonic the Hedgehog 3 and Sonic & Knuckles).
 * After you restore a stage in the Console/PC version, on the levels you can hear background noises, faint from the background music. On Green Hill, Sky Sanctuary, Seaside Hill and Planet Wisp you can hear birds, or whales. On Chemical Plant, you'll hear construction noises. On City Escape and Rooftop Run you'll hear people talking or walking. On Speed Highway, you'll hear cars moving.
 * Even though Sonic restored color to Crisis City, he didn't really restore life to the city, as it's still dead and barren of people.
 * Although Super Sonic is freely playable after beating the game, he has been altered since the Mega Drive games. He accelerates faster and still hovers just above the ground instead of running, but his top speed and jumping height remain unchanged. The rings necessary to hold the transformation also deplete faster than before, probably because unlocking him requires significantly less effort than in past titles.
 * Classic Sonic in his super form retains his black eyes (like in Sonic 2) instead of changing to the blue green eyes from Sonic 3 and Knuckles. Coupled with his lack of the jump attack from Sonic 3 and the fact that only Classic Tails is also shown, it is possible that Classic Sonic comes from the time between Sonic 2 and Sonic 3.
 * In the console storyline, the Time Eater appears when Sonic Party is happening, In the 3DS storyline, the Time Eater appears before the party happens.
 * Even though Sonic is supposed to relive his past, the 3DS version has Sonic go through Radical Highway stage and later has to fight the Biolizard from Sonic Adventure 2. In the original version, Shadow went through Radical Highway and fought the Biolizard, not Sonic.
 * On the console version, Classic Sonic and Modern Sonic fight each rival (Classic Metal Sonic, Shadow the Hedgehog, minus Silver the Hedgehog) in the areas he fought them in the original games, but the 3DS version has Sonic fight them in areas he didn't fight them in the original.
 * In the 3DS version, Big Arm is the only boss Sonic truly fought himself (Shadow fought the Biolizard, and Sonic fought Egg Emperor, but with Tails and Knuckles).
 * This is the second game to use skill customization, the first being Sonic and the Secret Rings