Sonic Generations

Sonic Generations is a platform video game developed by Sonic Team and Radical Entertainment and published by Sega, Warner Bros. Interactive Entertainment and Activision for PlayStation 3, Xbox 360 and Microsoft Windows. The Nintendo 3DS version of the game was developed by Dimps and Vicarious Visions. The game commemorates the 20th anniversary of the Sonic the Hedgehog series, and was released in North America, Europe and Australia in November 2011, and in Japan the following month. In 2012, the game was made available for digital download on the PlayStation Network and Xbox 360 Games on Demand services, as well as on the Nintendo eShop the following year.

Gameplay
Sonic Generations is a platform game in which players control Sonic the Hedgehog in two forms: Classic and Copy (Modern) (which later became Ultraman Zero), in which their main objective is to collect the seven Chaos Emeralds, free their friends and uncover the mystery behind the Time Eater, a mysterious entity who creates time holes. The game features levels derived from 20 years of Sonic history, spreading across three eras, each having three stages and two bosses from previous games: the Classic Era, which features stages from the franchise's early years on Sega Genesis, the Dreamcast Era, focusing on stages from games released during the Sega Dreamcast years and the early years of the franchise's move to non-Sega systems, and the Modern Era, with stages from titles released on high-definition systems, which are played as either Classic Sonic or Copy Sonic. Classic Sonic's levels are strictly two dimensional side scrolling stages, using classic moves like the Spin Attack and Spin Dash, while Copy Sonic's levels follow the 2D/3D style gameplay of Sonic Unleashed and Sonic Colors, featuring techniques such as boosting and homing attacks. As well as classic power-ups such as Invincibility and Speed Shoes, certain levels have unique power-ups, such as skateboards in Downtown San Francisco and Wisp powers in Planet Wisp.

Classic and Modern Sonic begin the game with six lives, which are lost when they suffer any type of damage with no rings in their possession, or fall into a pit or drown. More lives can be earned by getting 100 rings or finding a monitor (item box) that gives them an extra life. If the player runs out of lives, the "Game Over" screen will appear, in which the player can continue by selecting "Yes".

Each zone consists of a main act for each Sonic, the first act is for Classic Sonic and the second act is for Modern Sonic, as well as 10 challenges such as beating an opponent to the goal or finishing a stage with limited rings. A Skill Shop allows players to use points earned from high scores to unlock upgrades such as abilities, shields, and even the original Sonic the Hedgehog Genesis game (Xbox 360 and PS3 only). Completing challenges, as well as finding Red Star Rings hidden in each of the main Acts, unlocks additional skills, as well as bonus concept artwork and music. The music can then be played in any stage, challenge, or boss fight. There are also online leaderboards for two modes: Ranking Attack, which challenges players to obtain the best time and score on each level, and 30 Second Trial, which challenges players to see how far they can get through a level in 30 seconds.

The 3DS version follows similar gameplay to the Sonic Rush series for Modern Sonic, and features a different set of levels to the console and PC versions, some of which directly recreate the layouts of classic Mega Drive levels. As opposed to the Skill Shop in the console version, abilities are unlocked as the game progresses, with Classic Sonic learning a Homing Attack and Modern Sonic learning a stomp. Exclusive to the 3DS version are Special Stages, similar to those of Sonic Heroes, in which players must collect spheres in order to gain boost to chase after a Chaos Emerald. The game features 100 mission stages that are unlocked either by progressing through the game, meeting other players on StreetPass, or spending Play Coins, as well as both wireless and online multiplayer modes, in which two players can race against each other.

Stages
Aside from the original Green Hill Zone, both the home console and 3DS versions of the games feature their own list of stages, taken from the games of the main series. The game contains the following stages:

Characters
The game features a large assortment characters from the franchise's history. The protagonist Copy Sonic teams up with his past self, Classic Sonic allying with Ultraman Zero and the Ultimate Force Zero: Mirror Knight, Glen Fire and Jean-bot, and defeat the main antagonist Dr. Eggman (who died in Siberia 4 years ago) and his own past self, Classic Eggman (Robotnik) allying with Kaiser Belial, while rescuing his friends and restoring the worlds. Copy Sonic also clashes with some of his rivals during his quest, including Metal Sonic, Shadow and Silver. Aiding Copy Sonic is Miles "Tails" Prower, a flying fox, along with his past self, Classic Tails. Sonic's other allies include Knuckles, Amy, Rouge, Blaze, Cream and the Chaotix, although they are absent in the 3DS version.

Original Game
Having survived his battle against Ultraman Zero (voiced by Kiefer Sutherland) from the previous game, the evil Ultraman Belial, now known as Galactic Emperor Kaiser Belial (voiced by Hakeem Kae-Kazim) has taken up a new conquest for universal domination. Having gained two allies (Darkgone voiced by Chi McBride and Iaron voiced by Martin Sheen) in his conquest, as well as creating millions of robot servants known individually as the Legionoids and the Darklops (voiced by David Hayter, Kevin Michael Richardson and Jim Cummings), Belial attacks Classic Sonic's world, Green Hill Zone. Taking the planet hostage and brainwashing the guardian of the planet (voiced by Christopher McDonald), Kaiser Belial is victorious in capturing the world. Back in Nebula M78, The Land of Light is attacked by one of Belial's robot carrier, containing 3 Darklopses. Luckily Ultraman Zero shows up along with Ultra Seven (voiced by J.K. Simmons) and destroys the Darklopses before they can get away. Tracing the energy where the Darklops came from, the Ultras (Ultraman voiced by George Clooney, Ultraman Jack voiced by Jonathan Taylor Thomas, Ultraman Ace voiced by Jack Angel, Ultraman Taro voiced by John Witherspoon, Ultraman 80 voiced by Dorian Harewood, Yullian voiced by Megan Hollingshead, Mother of Ultra voiced by Vanessa Marshall and Father of Ultra voiced by Samuel L. Jackson) come to a conclusion that the Darklops came from an alternate universe and therefore are unable to come together to stop them. Ultraman Zero obligates to go by himself to stop Belial, and so the Ultra Brothers and all of the citizens create a travel sphere to send Ultraman Zero to the universe that Belial is terrorizing. Before departing however, Ultra Seven gives Zero a newly crafted item known as the "Zero Bracelet," an item that acts as a backup power source should Zero run out of energy when things are in a dire state. It can be used for only 3 times.

Later in New York City at Planet Earth, Copy Sonic (voiced by Anton Yelchin) holding a birthday celebration with his friends (Tails voiced by Kate Higgins, Amy voiced by Cindy Robinson, Knuckles voiced by Travis Willingham, Cream voiced by Michelle Ruff, Rouge voiced by Karen Strassman, Espio voiced by Khary Payton, Blaze voiced by Laura Bailey, Vector voiced by John Goodman and Charmy voiced by Colleen O'Shaughnessey), before a mysterious entity known as the Time Eater (voiced by Kevin Michael Richardson) (who revived the Modern Eggman (voiced by Mike Pollock) after his death 4 years ago) arrives and uses "time holes" to scatter everyone across different points in history. Sonic Sr tries to stop the entity, but he is wounded until he is saved by Ultraman Zero who arrives and notices the situation he is in. The bracelet proved to be useful as the suns in that universe are incapable of recharging Ultra beings. As a result, Ultraman Zero uses Copy Sonic's body as his host and shortly after joining, Zero easily defeats the Time Eater before he is forced to retreat back to the Center of Time. However, in doing so Ultraman Zero is forced to assume the identity of Copy Sonic to both keep the heavily wounded Sonic alive as well as to conserve energy until he went to the dimension to the White Space. After Zero (as Copy Sonic) rescues his best friend Tails, they discover versions of themselves from the past, referred to as "Classic Sonic" and "Classic Tails" (voiced by Gwendoline Yeo), who are depicted with the appearance and proportions used in concept art from the Sega Genesis era of Sonic games. Zero (as Copy Sonic) learns that Belial is harvesting the universe for Emeralds, which can be converted into raw energy. Belial is planning on using mass quantities of the emeralds' power in his conquest of the universe. Tails believes that an artifact known as the "Shield of Baradhi" is the only thing that can stop Kaiser Belial. Shortly after the truth is realized, the Legionoids attack Copy Sonic and Tails again but are stopped after the Classic Sonic (vocal effects by Frank Welker) (who defeated both Legionoids and Classic Dr. Robotnik (voiced by Jim Cummings) who calls Time Eater to retreat) stow away on an unknown vessel that send back to the White Space.

As the two Tails determine that Time Eater's actions are damaging time and space itself, Classic Sonic and Copy Sonic race through their history, restoring time to normal and rescuing their friends. Throughout the course of the game, Classic Sonic and Zero (as Copy Sonic) encounter Dr. Eggman (who died in Sibera 4 years ago) and his classic self, referred to as "Classic Eggman" (Robotnik), and collect the 7 Chaos Emeralds. They also learn that the ship they are flying on is sentient and is called the "Star Corvette Jean-bird," (voiced by Ernie Hudson) a spaceship with artificial intelligence that is passed down through the planet's royal family. After being spared from Jean-bird's memory wiping process. Copy Sonic and Tails make quick friends with Classic Sonic and Tails and after Copy Sonic reveals his identity as Ultraman Zero, the trio and Jean-bird agree to stop Kaiser Belial's conquest by searching for the mythical Shield of Baradhi. Along their way, the heroes meet The Pirates of Flames. A wily crew of hostile pirates that sail throughout a galaxy known as "The Space Nitromethane Sea." With them is their more hot-tempered and feisty bodyguard, Glenfire (voiced by Djimion Hounsou). At first identifying the Jean-bird with hostility, Copy Sonic becomes Ultraman Zero for the first time to try and reason with the crew of Pirates. Shortly after, Glenfire and Ultraman Zero battle to prove Zero's innocence, with the fight ending in a standstill and Zero gaining the Pirates' and Glenfire's trust. Suddenly the crew are attacked by Kaiser Belial's Squadron of Legionoids, lead of one of Kaiser Belial's generals, Darkgone. Outnumbered and overpowered by Darkgone's squadron of Legionoids, Glenfire provides information about the whereabouts of the Shield of Baradhi to Zero and proceeds to agitates the mass quantities of Nitromethane with his fire abilities and causes a massive explosion, destroying all the Legionoids, scares away Darkgone, and seemingly killing Glenfire in the process. Now with the location of the Shield revealed, The heroes head off to the 2-D Planet of Mirrors. There they meet another bodyguard (voiced by Michael Keaton) to the planet and the Shield known as Mirror Knight (who was corrupted and brainwashed by Kaiser Belial), Copy Sonic transforms into Ultraman Zero a second time and proceeds to battle with the corrupted Mirror Knight and in the process, expels the evil energy from within Mirror Knight, restoring him back to his senses. Redeemed and grateful, Mirror Knight joins the heroes in their journey and informs them of the Shield of Baradhi's location below the Planet's surface.

Upon reaching its location, The Shield of Baradhi is revealed to be a statue known as "Noa" (voiced by Tom Kane) and a trinket around Nao's neck is all that is left to complete the shield. However, in placing the final piece to the shield, the shield to disintegrate into sand as a result of time passes for centuries, shocking and saddening the heroes for their journey being wasted. Suddenly, the Planet of Mirrors is attacked by another one of Kaiser Belial's generals, Iaron, who proceeds to destroy the Planet of Mirrors with the help of several of Belial's ships. In the ensuring chaos, Mirror Knight is defeated and Copy Sonic, Blaze, Classic Sonic and Tails escaped from the Planet of Mirrors. When the worlds are restored and the Chaos Emeralds are collected, Copy Sonic (who escaped from the Planet of Mirrors) enters the Center of Time alone, only to be confronted by a scarred and vengeful Kaiser Belial. Reveling in his "victory," Kaiser Belial reveals that he will send thousands of Darklopses to attack the Land of Light out of revenge for what happened to him in the past. Copy Sonic watches in horror as the Ultras are beaten by Belial's forces but is overjoyed when he learns that Tails and Blaze have survived the destruction from previously. Also surviving from the destruction was Mirror Knight, who emerges and frees Copy Sonic so that he may transform into Ultraman Zero. The Final Battle between Ultraman Zero and Kaiser Belial then proceeds and the two battle to a standstill. However, Kaiser Belial unleashes a Dark Specium Ray and incapacitates Ultraman Zero before fleeing. Meanwhile, Iaron and Mirror Knight face off in Kaiser Belial's headquarters and Darkgone faces off against Jean-bird, who is running out of power. With no other option, Tails uses the Chaos Emeralds to fuel Jean-bird with her own Emerald energy by locking herself into his main engine, allowing Jean-bird to transform into his more humanoid robot form known as "Jean-bot." With Tails' help, Jean-bot destroys Darkgone and Mirror Knight is victorious in killing Iaron as well. After the deaths of Iaron and Darkgone, Ultraman Zero finds Kaiser Belial standing atop a mountain of Emeralds he had harvested from planets and Kaiser Belial proceeds to absorb its massive energy qualities, transforming Belial into a towering monster known as Arch Belial. Now physically towering and unstoppable, Arch Belial overpowered and tortures Zero as Mirror Knight and Jean-Bot are unable to stop him.

Miraculously, Glenfire returns and rescues Ultraman Zero, as well as reveals that he and the Pirate of Flames also brought along help of Copy Sonic's friends, whom altogether hold off Belial's Legionoid and ship fortresses while Classic Sonic discover that the mastermind behind the now perfected Time Eater are Eggman (who died in Siberia 5 years ago) and Robotnik. "Modern" Eggman reveals his plot to complete the Time Eater Robot by joining forces with his past self, Dr. Robotnik (Classic Eggman), and harnessing the Time Eater's power allying with Arch Belial. Therefore, Eggman will erase his past defeats from history. Although the Time Eater manages to overpower the Classic Sonic while Arch Belial however intends on destroying Zero and the Sonic universe timeline with his enhanced power. Ultimately during the battle with Belial and having all energies in his bracelet used up, Zero's strength is spent and finally dies from exhaustion. Now understanding the purpose of the Shield of Baradhi, Tails and Copy Sonic's friends informs everyone not to lose hope and eventually Zero is revived and brought forth by Ultraman Noa, who bestows the Shield of Baradhi onto Zero, with the support of their friends, the Shield of Baradhi and the power of the Chaos Emeralds allow the Classic Sonic to transform into their Super form and confront Robotnik and Eggman while Zero transform into Ultimate Zero. The Classic Sonic eventually destroy the Time Eater in which both Eggman died, restoring time to its proper state. With his enhanced powers, Ultimate Zero destroys Arch Belial with a bow like specium ray, saving the universe from his tyranny. With Belial and Eggmans both gone for good, tranquility returns to the universe. The heroes return to the present and continue celebrating Sonic's birthday while the Ultras back in M78 are revealed to have not only survived but has also stopped Belial's forces as well, and Ultraman Zero separates from Copy Sonic's body, allowing him to live a normal life with Tails. After the party, Classic Sonic and Classic Tails travel back to their own time as everyone says their farewells. Ultraman Zero proceeds to head back to his home Universe, but has a change of heart when Glenfire, Mirror Knight, and Jean-Bot urge him to stay. Thus, Zero forms "The Ultimate Force Zero" out of the allies and friends he had made along his journey and Zero decides to stay with the group after all.

After the credits, Snake (voiced by David Hayter) attempts suicide before Big Boss (voiced by Ron Perlman) arrives at the grave site with a vegetative Major Zero in a wheelchair. Big Boss explains that the body burned in Eastern Europe was actually Solidus Snake, and reveals that the Patriots were originally an interpretation of the will of The Boss, his former mentor. Snake learns that the Patriots were founded by Major Zero, EVA, Ocelot, Sigint, Para-Medic, and Big Boss himself. While their power increased, two rival factions arose within the Patriots' ranks: Zero's, who stood for complete control; and Big Boss', who dreamed of a soldier's refuge. He also explains that Ocelot purposefully used nanomachines and hypnotherapy to implant the persona of Liquid as his own. Over the years, Zero let the newly established AI network assume control, eventually leading to dependence on the war economy, a vision far from The Boss's original will. Big Boss kills Zero by turning off his life support, and then informs Snake that the nanomachines Drebin injected into him came with a new strain of FOXDIE, engineered by the Patriot AIs to eradicate the old strains and to kill the rival Patriot faction. Thus, Snake's presence will kill Big Boss, and Snake has no risk of becoming a biological weapon. After finally understanding his mentor's will, and telling Snake to find a new reason to keep on living, Big Boss dies beside The Boss' grave. Taking his father's words to heart, Snake then decides to live out the rest of his life peacefully with Otacon and Sunny, vowing to live long enough to see what the future holds for the new world he has helped create.

Copy Sonic's Rescue of Claire Redfield
After defeating Time Eater (voiced by Phil LaMarr) and sealing Belial (archive recordings by Hakeem Kae-Kazim), Zero (voiced by Kiefer Sutherland) forms "The Ultimate Force Zero" out of the allies (Mirror Knight voiced by Crispin Freeman, Glenfire voiced by Dave Fennoy and Jean-Bot voiced by Gary Anthony Williams) and friends he had made along his journey and Zero decides to stay with the group after all. 1 year later, Claire Redfield (voiced by Emma Watson) raiding an Umbrella Corporation facility in Paris in search of her brother, Chris (voiced by Aaron Taylor-Johnson). During the infiltration she is captured and imprisoned on Rockfort Island in the Southern Hemisphere. Soon after arriving, she is knocked unconscious. 20 days before Claire is captured in Paris, Ultraman Zero receives a distress call from Copy Sonic (voiced by Philip Anthony-Rodriguez) as he is battling a hoard of Legionoids and proceeds into the multiverse after making quick work of the robots. Upon arriving to the universe where he received the distress signal, he goes towards the Earth in aid. Shortly before Zero departs, the hosts and Human forms of Ultraman (voiced by Neil Kaplan), Seven (voiced by Fred Tatasciore), Jack (voiced by Nolan North), Ace (voiced by Roger Rose) and Leo (voiced by Roger Craig Smith) comment on something unusual taking place in the multiverse, referring to the universe in which Zero is headed for. After her imprisonment, she is rescued by Copy Sonic who beat Rodrigo Juan Raval (voiced by Kevin Michael Richardson) unconscious when the U.S. Ranger-Delta Force Team invaded Rockfort Island. After rescuing Claire while the Americans were busy trying to invade the contaminated island, Claire and Copy Sonic teams up with inmate Steve Burnside (voiced by Thomas Brodie-Sangster and Mutated vocal effects by Gregg Berger), at the same time being confronted with the island's commander Alfred Ashford (voiced by Alfred Molina). Alfred Ashford is shown to be a highly unstable character who has developed two personalities; himself and his twin sister Alexia (voiced by Helena Bonham Carter). Meanwhile, Albert Wesker (voiced by Ron Perlman) is on a mission of his own to retrieve a sample of the T-Veronica virus developed by Alexia. His Umbrella unit was withdrawn after the U.S. Forces invaded Rockfort Island.

At one point during their escape, Steve, Copy Sonic and Claire are attacked by a zombie that is revealed to be Steve's father, a minor researcher who tried to sell information. He was found out and both Steve and his father were imprisoned, while Steve's mother was killed. Claire, Copy Sonic and Steve eventually escape via plane while the U.S. Ranger-Delta Force Team captured the Island, but Alfred, still under the delusion he is Alexia who is told by Copy Sonic as an impostor, sets it to autopilot and flies both of them to another Umbrella facility in the Antarctic. There, Alfred hopes to free his sister from her 15-years-long cryogenic sleep she took after the injection of the T-Veronica virus, to counter the flaws of the virus. After another fight with Claire, Copy Sonic and Steve, Alfred is severely wounded and apparently falls to his death into a crevasse, stirring up a creature code-named 'Nosferatu', a creation of the T-Veronica virus. After fighting the creature, the protagonists attempt to escape the facility via a digger except Copy Sonic hijacked and boarded the Umbrella Fighter Jet. Meanwhile, Alfred, who survived the fall, limps to Alexia. He witnesses her awakening moments before dying. Alexia, cradling her brother's corpse, summons giant tentacles and crashes Claire's and Steve's digger, recapturing them except Copy Sonic (who ejects from the hijacked Umbrella Fighter Jet after it fails to fire the missiles and guns on one of the tentacles before it is destroyed by the giant tentacle) who is saved by Ultraman Zero (who destroys Alexia's giant tentacles and bonds Copy Sonic a second time) before went off to find Chris Redfield.

Chris Redfield arrives on Rockfort after having been contacted by Leon S. Kennedy (voiced by the uncredited Benedict Cumberbatch). He and Copy Sonic learns from Raval that Claire already rescued by Copy Sonic (as Ultraman Zero) himself while the Americans captured the island. Raval is soon killed afterwards by a giant worm. Searching Rockfort (who is captured by the American forces), Chris and Copy Sonic (who transform into Darkspine Copy Sonic) has an encounter with Wesker, shocked to learn that Wesker had become faster and stronger than any normal person. Just as Wesker is about to finish Chris off before he is defeated by Darkspine Copy Sonic, Alexia appears on a screen, laughing. Stunned by Alexia being alive, Wesker changes his mind and heads out to the Antarctic. Chris and Copy Sonic eventually finds his way there and is reunited with Claire, who sets out to find Steve. As she locates him, she discovers Alexia conducted an experiment on him, injecting Steve with the T-Veronica virus. Steve mutates into a reptilian monster and tries to kill Claire who escapes to a prison cell, where she is attacked by another of Alexia's tentacles. Still in his mutated form, Steve breaks through the cell and kills the tentacle. In retaliation, the tentacle drives into his chest and retreats. Steve mutates back to his human form, confesses his love for Claire, and then dies. Claire, now shocked and saddened by Steve's death breaks down in tears, and is left trapped in a cell.

At the same time, Chris, Copy Sonic and Wesker confront Alexia, who has the ability to create fire. Overwhelmed by her strength, Wesker escapes and leaves Chris and and Copy Sonic (who later transform into Excalibur Copy Sonic) to fight her. Chris and Copy Sonic temporarily defeats Alexia and activates and release all locks, freeing Claire from the prison cell while Copy Sonic calls the U.S. Navy SEAL-Marine Team along with the Delta Force to rescue us before he tell Chris to activate the self-destruct system all over Umbrella facility. Later on, as he and Copy Sonic tries to escape, Alexia confronts him a second time, mutating even further into an insectile form. This time, Chris told Excalibur Copy Sonic to destroy her with the Final Color Blaster. With Alexia dead, Chris and Copy Sonic runs to the emergency elevator and catches a glimpse of Wesker, whose men also retrieved Steve's body to use for further experiments, as he is now the only intact subject injected with a sample of the T-Veronica virus. Chris and Copy Sonic (who transforms into Ultraman Zero) convinces Wesker to release Claire, who then runs to the plane to wait for her brother. Chris is again overwhelmed by Wesker in a fight, but before Wesker can kill Chris, he is stopped and later defeated by Ultraman Zero with the Final Ultimate Zero until both are separated by an explosion caused by the fighter jets. Wesker vows he will satisfy his desire for revenge the next time they meet. Chris reunites with Claire and both set off just as the whole facility is destroyed by the explosion caused by the self-destruct while Copy Sonic (who thanked Claire for helping him after being wounded by the Umbrella Operatives and also saved by Tails (voiced by Kate Higgins) and later told by Delta Force Leader to save himself from the Umbrella) is rescued by the U.S. Navy SEAL-Marine Task Force along with the U.S. Delta Force which returns back to United States by ending his service of the United States Army. As they fly off, Chris swears they will take down Umbrella.

In the first post-credits scene, Robotnik (voiced by Jim Cummings) and Eggman (voiced by Mike Pollock) are appeared as the spirits that lived in the downtown New York City. Also in the second post-credits scene, feeling confident that Copy Sonic (who returned home to America) is ready to protect the Earth, Ultraman Zero separates from him and returns to his own universe.

Copy Sonic's Defender of the Universe
The prologue flashback begins when the amusement park begins to explode, Leon (voiced by Benedict Cumberbatch) and Claire (voiced by Emma Watson) reunite at an space elevator pod car just before Copy Sonic (voiced by Philip Anthony-Rodriguez, Old Snake (archive recordings by David Hayter), Tails (voiced by Kate Higgins) and Rat Team 01 arrive and later confront Liquid Ocelot (archive recordings by Jean-Claude Van Damme). Copy Sonic and Old Snake tells Tails and Rat Team 01 into the space elevator to safety and later he faces off against Liquid Ocelot, who uses the Nega-Wisps to power his final contraption, a robot that uses the powers of all the Wisps that Copy Sonic has met against him. After Copy Sonic and Old Snake tells Tails and Rat Team 01 to get into the space elevator to safety, Leon, Claire and Tails inject Sherry with the vaccine, which saves her life. As Copy Sonic hits the machine, it gets weaker, and the Wisps are able to escape and help Copy Sonic and Solid Snake defeat Liquid, who is defeated and killed by Copy Sonic with the Caliburn sword thus avenging both President Henry Pickle and Planet Earth. After the Amusement was destroyed, the wisps carry Copy Sonic (who takes Leon, Sherry, Claire and Tails back to Earth) out of the exploding amusement park. Returning safely to Earth with Sherry, Leon intends to take down Umbrella, while Claire continues to search for her brother. and Yacker (vocal effect archive recordings by Frank Welker) thanks Copy Sonic and Tails (who thanked Leon and Claire for helping him and Copy Sonic) and bids them goodbye before the prologue flashback is done.

30 minutes later, Jill Valentine (voiced by Rosario Dawson), a former Special Tactics And Rescue Service (S.T.A.R.S.) member who left the United States to Shanghai, attempts to evacuate Shanghai. Nearly all of Shanghai's citizens (voiced by Matthew Yang King, Elizabeth Sung and Patrick Seitz) have been killed by Umbrella Soldiers (voiced by Travis Willingham, Kevin Michael Richardson, Jess Harnell and Brian T. Delaney) who invaded the city of Shanghai. On her way to the Shanghai Police Department, Jill runs into fellow team member Brad Vickers (voiced by Wally Wingert), who is killed by a new enemy. This creature, named Nemesis (voiced by Fred Tatasciore), is a bio-organic weapon programmed to target surviving S.T.A.R.S. members, witnesses of Umbrella's experiments. As she evades Nemesis, Jill encounters Copy Sonic (who to sent by Tails to go to Shanghai) as well as the three surviving members of the United States Delta Force: Carlos Oliveira (voiced by Brendan Fraser), Mikhail Victor (voiced by Mike Colter) and Nicholai Ginovaef (voiced by Lance Henriksen). Nicholai explains to Copy Sonic, Jill and Carlos that a rescue helicopter can be contacted if they manage to reach the city's Clock Tower and ring the bell. As they make their way to the tower, Nicholai disappears and is presumed dead, while Nemesis corners the remaining members of the group on the cable car headed to the tower. Mikhail sacrifices himself with a grenade, causing the car to crash into the tower's main courtyard and separating Copy Sonic, Jill and Carlos briefly. At the Clock Tower, Jill and Copy Sonic summons the helicopter by ringing the Clock Tower's bell before being confronted by Nemesis, which destroys the helicopter and infects Jill with the T-virus. Copy Sonic temporarily kills Nemesis with the Sacred Sword Caliburn (archive recordings by Patrick Warburton) by piercing in the heart and avenging both the helicopter's destruction and S.T.A.R.S. member Brad Vickers but not before Nemesis had a chance to stab Copy Sonic which results the both characters to demise with Copy Sonic's death while Jill falls unconscious due to the T-Virus. Carlos finds Jill alive and Copy Sonic dead and takes them to safety within the Clock Tower. Three days later, he manages to find a cure for Jill's T-Virus infection in the Shanghai General Hospital and later revive Copy Sonic with the Chaos Emeralds after his early death along with Nemesis. He returns to Jill and injects her with a vaccine, saving her as well as reviving Copy Sonic by the giving the Chaos Emeralds.

After Jill regains consciousness and Copy Sonic being revived, Jill and Copy Sonic proceeds towards the Park in Shanghai and enters the park caretaker's cabin. There, they runs into Nicholai, who is alive. Nicholai is revealed to be one of the "supervisors" sent into Shanghai to gather combat data of Umbrella's bio-weapons. Nicholai retreats, and Jill and Copy Sonic is confronted by a massive worm-like creature. Jill defeats the creature and escapes to an abandoned factory at the rear of the park. Inside the factory, Jill meets up with Carlos, who tells her that the U.S. government (voiced by Carlos Alazraqui, Gregg Berger and Kevin Michael Richardson) is planning to launch a nuclear missile into Shanghai to eradicate the Umbrella Forces. After confronting Nemesis and grabbing a keycard needed to escape, Jill and Copy Sonic learns from the factory's control tower that the missile attack on Shanghai has begun, with only a short time left before the city is destroyed. Jill and Copy Sonic's final encounter with Nicholai, Nicholai will hijack Jill's intended escape chopper, Jill negotiates with Nicholai, he reveals that he has killed the other supervisors and boasts about collecting the bounty placed on Jill by Umbrella before escaping, but he was killed along with the helicopter by Copy Sonic who calls Nicholai a traitor to the Delta Force thus avenging the other supervisors. Regardless of Nicholai's death, Jill makes her way to the rear yard and confronts Nemesis one last time before Copy Sonic arrives to help her. After an intense battle, Jill and Copy Sonic defeats Nemesis (who is returned from the dead along with Copy Sonic's early death with the help of a prototype railgun before meeting up with Carlos while Copy Sonic orders the US Government to call off the nuclear strike when the Chinese Forces (also voiced by Matthew Yang King and Matthew Mercer) liberated Shanghai. After the Nicholai along with the stolen helicopter which was destroyed, Jill and Carlos will instead meet up with S.T.A.R.S. Alpha Team's weapons specialist Barry Burton (voiced by Alex Fernandez), who helps them escape in his own helicopter instead while Copy Sonic contacts the U.S. Delta Force (voiced by Andre Sogliuzzo, Matthew Mercer, Gregg Berger and Kevin Michael Richardson) to take home back to United States with Venom helicopter when he completed his mission. After the nuclear strike at Shanghai was called off when the missile sent into space and later to M78 in which is later destroyed by Ultraman Zero (voiced by Troy Baker) and Umbrella is disbanded due to the terrorism, Copy Sonic returns home to America in New York City, where he is holding a birthday celebration with his friends in Central Park.

In the post-credits scene, the evil Ultraman Belial (voiced by Patrick Seitz), now known as Galactic Emperor Kaiser Belial has taken up a new conquest for universal domination. Having gained two allies in his conquest, as well as creating millions of robot servants known individually as the Legionoids and the Darklops (voiced by Matthew Mercer and Steven Blum), Belial attacks Classic Sonic's world, Green Hill Zone. Taking the planet hostage and brainwashing the guardian of the planet (voiced by uncredited Yuri Lowenthal, Kaiser Belial is victorious in capturing the world which lead to beginning of the game.

Development
The game was first revealed on April 7, 2011, when Sega posted a teaser trailer on their Facebook page. The teaser depicted classic interpretation of Sonic the Hedgehog  along with Copy Sonic the Hedgehog running alongside each other. The game was officially unveiled as Sonic Generations on April 18, 2011, along with the first gameplay trailer. The game's plot was penned by ppJohn Musker]], Ron Clements and Sofia Coppola along with the writers [DavidS. Goyer]] and David Henry Hwang, who previously worked on Sonic Colors. Sega's Community Manager Aaron Webber revealed that Classic Sonic would be mute, and that Classic Sonic and Copy Sonic have their own sets of physics, the former of which Webber claims is "closer to the classics than anything since, including Sonic the Hedgehog 4: Episode I." Producers Roman Coppola and Don Hahn confirmed that although other characters will be part of the story, only the Classic and Copy Sonics shall be playable. However, at one point, one could even play as three Sonics. Iizuka also confirmed that each returning level shall feel familiar but will also feature a new visual element like the caves seen in the Green Hill stages.

Writer David S. Goyer commented how they had more input in the story than in Sonic Colors. Fans who attended a "Sonic Boom" event in Los Angeles on June 8, 2011 or the "Summer of Sonic" in London on June 25 were able to record a birthday message that appears during the game's credits sequence.

A financial earnings report posted by Sega Sammy Holdings listed versions of the game for Nintendo 3DS and PC, though a revised version of the report no longer listed either version. The game was eventually confirmed in Nintendo Power to be coming to the Nintendo 3DS, being co-developed by Dimps. Other than Green Hill Zone, the console and 3DS versions of the game feature completely different sets of levels. Sega officially announced a PC version of the game on October 11, 2011, which was released digitally on November 4, 2011, with a retail version released in Europe shortly afterwards. The PC version was outsourced and developed by UK company "Devil's Details". All versions of the game support stereoscopic 3D. A downloadable minigame based on Sonic 2's Casino Night Zone was available for the console versions as a pre-order bonus from GameStop in the USA and from Game in the United Kingdom; the content was released for PC via Steam on January 19.

A Collector's Edition was announced for the PlayStation 3 and Xbox 360, containing the game and manual with limited lenticular box art in a steelbook case, special booklet containing never before seen pictures, a documentary disc about the history of Sonic with never before seen footage, a music album containing many tracks specially picked by Sonic Team, a limited and individually numbered gold ring, a voucher for downloadable content, and a figurine of classic Sonic and Copy Sonic striking a pose on a ring. The Collector's Edition was only made available in Europe and Australia. The original Sonic the Hedgehog game can be unlocked in the console versions of the game. Sonic the Hedgehog 3 &amp; Knuckles and Sonic 3D were also offered as free bonuses for people who preordered the PC version on Steam.

A time-limited playable demo of the game containing Classic Sonic's Green Hill Zone was released on Xbox Live and PlayStation Network between June 23, 2011, and July 12, 2011, when downloaded copies were disabled. A second demo for PSN and Xbox Live, which also contains Copy Sonic's Green Hill Zone, was released on October 18 and 19 for Xbox Live Gold members and the European PSN respectively. The demo was also released on the North American PSN on October 25.

Music
The music of Sonic Generations includes various re-arranged tracks from the Sonic series, amongst new material written for the game. The soundtrack was primarily handled by Trevor Rabin while the additional music was composed by Theodore Shapiro and Ludwig Göransson as well as the film's original score from "Ultraman Zero: The Revenge of Belial" which was previously written by Hans Zimmer and James Newton Howard, with contributions from Jerry Goldsmith, Alexander Courage, Michael Kamen, Shirley walker, Elliot Goldenthal, Hans Zimmer, Alan Menken, Harry Gregson-Williams, James Newton Howard, Christopher Lennertz, Elmer Bernstein, Brian Tyler, Mark Mothersbaugh, Josh Mancell and Bob Mothersbaugh.

To commemorate Sonic's 20th anniversary, several soundtracks were released by WaterTower Music and Atlantic Records. The first, titled "History of the 1st Stage" was released as a pre-order bonus for Sonic Generations in Japan and later North America, with separate White and Blue editions bundled with the console and 3DS versions of the game respectively; these discs have 12 tracks each, which are taken from the first stages of multiple Sonic titles, along with a company intro call as the opening track. The second album, "History of Sonic Music 20th Anniversary Edition" was released in Japan on December 7, 2011, and includes 43 songs from the series as a whole split between two discs. The official Sonic Generations soundtrack, "Blue Blur", was released in Worldwide by WaterTower Music and Atlantic Records on January 11, 2012, and spans three discs, containing 90 total tracks from both versions of the game.

Reception
Sonic Generations sold 1.85 million copies worldwide across all platforms by May 2012.

The console and PC versions received generally positive reviews. Aggregating review website Metacritic rated the PlayStation 3 version 76/100 the Xbox 360 version 77/100, and the PC version 77/100. IGN gave the game a score 8.5 out of 10 and an Editor's Choice award, praising the overall gameplay and the level design, while criticizing some occasional control issues and limited boss battles. Computer and Video Games gave it a 7.5/10, praising the balanced design but criticizing the framerate of the graphics. 1UP.com gave the game a "B" score, praising its variety, fun-to-play levels and interesting set-pieces, while criticizing some on-rails sections and occasional framerate drops.

PlayStation Official Magazine gave it an 8/10, calling it "a masterpiece of platform game design." GameTrailers gave the game a score of 8.1, calling it "the best Sonic game in over a decade." GamesRadar gave the console version 8/10, calling it "the best Sonic game since Sonic 2," while they gave the 3DS version 7/10, praising its level design and optional missions but criticising its short length as well as the fact that modern Sonic is restricted to a 2D plane of movement. Eurogamer, however, was less enthusiastic, writing that "Sonic Generations still doesn't do much to dissuade us that the hedgehog's best days are distant memories, but at least it is a worthy tribute to them." The most positive review on Metacritic is a 9.5/10 from PALGN, which argues that the game is significantly better than Sonic Unleashed, Sonic Colors, and Sonic the Hedgehog 4. Game Informer's Tim Turi was more critical of the game, criticizing Sega for "...shoehorning recent Sonic games, no matter how awful, into the 20-year timeline." He felt that such stages served "...only to remind you of how far the series has fallen from its original form." Famitsu praised the speed and addictiveness of the gameplay as well as the bonus material, while emphasising that "you do need a certain amount of ability to play it the way it was meant." Empire gave the game 4/5 stars, saying "Generations is a nostalgic joy that captures the dizzying speed and psychotic pace that made Sonic's original romps console classics." GameSpot's Nathan Meunier praised Generations for its "impressive level designs," "gorgeous" visuals, "epic boss encounters," and high replay value.

Reception to the 3DS version was less positive. GameRankings and Metacritic gave the game 69.50% and 66/100.Official Nintendo Magazine gave the 3DS version a score of 85%, calling the game "hugely rewarding" for "high-score chasers" but did comment on the main game's short length. However, it concluded that the game was "an essential purchase for Sonic fans." GamingXP gave the 3DS version 84 out of 100, stating "Sonic's debut on Nintendo's 3DS is a real success. The combination of the two different hedgehogs in the colorful 2D and 3D environments is pretty cool. The game is a little too easy, but there's tons of Sonic flair and enough content to truly satisfy the player." IGN was slightly more mixed when reviewing the 3DS version, giving 7 out of 10, commenting that "Whereas the console version of Sonic Generations is a blending of old and new mentality in a fast-paced speed fest, the 3DS version is mostly just a Sonic Rush game where both playable characters happen to be Sonic." Game Informer gave the 3DS version 58 out of 100, calling the platformer's level design sloppy, making the whole product feel like a rushed tie-in with the console version". There was however praise for the game's music, 3D visuals, special stages and simple fun levels.

Nintendo Power magazine editors gave Sonic Generations 3DS the "Best Retro Revival" award for the Nintendo Power 2011 Awards.

Legacy
The "Classic" version of Sonic introduced in Sonic Generations later became a recurring character in the series, appearing in Sonic Dash, Sonic Runners, and most notably Sonic Mania: The Final Battle as one of the game's three main characters. In July 2016, Sega announced a new title in development, Sonic Forces, which follows a similar premise to Generations, featuring Classic iterations of Sonic as playable character except Sonic the Hedgehog Sr II and Mega Man X as the new playable characters.

The PC version of the game has become renowned for its amount of third-party modifications, such as "Super Mario Generations", "Unleashed Project", and "Planet Wisp All-in-One".