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Sonic the Hedgehog CD,[a] commonly referred to as Sonic CD, is a 1993 platform game for the Sega CD. The story follows Sonic the Hedgehog as he attempts to save an extraterrestrial body, Little Planet, from Doctor Robotnik. As a Sonic the Hedgehog series platformer, Sonic runs and jumps through several themed levels while collecting rings and defeating robots. Sonic CD is distinguished from other Sonic games by its time travel feature, a key aspect to the story and gameplay. By traveling through time, players can access different versions of stages featuring alternate layouts, music, and graphics based on the time period.

Sonic CD
The North American cover art for Sonic CD, depicting Sonic fighting Metal Sonic for one of the Time Stones. The game's logo is shown atop the two; the Sega CD banner is on their left; and beneath them is the Sega logo, Seal of Quality, and the game's rating.
North American cover art
Director(s)Naoto Ohshima
  • Minoru Kanari
  • Makoto Oshitani
Programmer(s)Matsuhide Mizoguchi
Artist(s)Hiroyuki Kawaguchi
SeriesSonic the Hedgehog
Platform(s)Sega CD, Windows, GameCube, PlayStation 2, Android, PlayStation 3, Xbox 360, iOS, Windows Phone, Ouya, Apple TV, Fire TV

The Sega CD's flagship game, Sonic CD was conceived as an enhanced port of Sonic the Hedgehog 2, but was reworked after lackluster sales of Sonic 2 in Japan. Sonic co-creator Naoto Ohshima directed and Sega developers designed the game to show off the technical capabilities of the Sega CD. The game features the debuts of Amy Rose and Metal Sonic, and includes animated cutscenes produced by Toei Animation. Two soundtracks were composed for the game: the original score was composed by Naofumi Hataya and Masafumi Ogata, while the North American score was composed by members of Sega Technical Institute.

Sonic CD is often called one of the best games in the Sonic series and the platform game genre. Reviewers praised its exceptional size, music, and the time travel feature, although some also believed the game did not use the Sega CD's capabilities to its fullest. It sold over 1.5 million copies, making it the Sega CD's bestseller. The game was ported to Windows as part of the Sega PC brand in 1996, and to PlayStation 2 and GameCube as part of Sonic Gems Collection in 2005. A remastered version, developed by Christian Whitehead using the Retro Engine, was released for various platforms and mobile devices in 2011.


(Clockwise from top left) The past, present, good future, and bad future variants of the game's first level, Palmtree Panic

Sonic CD is a side-scrolling platform game similar to the original Sonic the Hedgehog. Players control Sonic the Hedgehog as he ventures to stop his nemesis Doctor Robotnik from obtaining the magical Time Stones and conquering Little Planet.[1] Like previous games, Sonic can destroy enemies and objects (such as certain walls and television monitors containing power-ups[1]) by rolling into a ball, and collects rings as a form of health. Sonic can also perform a "spin dash" and a "super peel-out" that can increase his speed.[2] The game is split into seven levels called rounds; each round is split into three zones, the third of which culminates in a boss fight with Robotnik. Players start with three lives, which are lost when they suffer any type of damage without rings in their possession; losing all lives results in a game over.[3][4]

Sonic CD is differentiated from other Sonic games through its time travel game mechanic, which allows players to access different versions of stages set in the past, present and future.[5] Sonic starts the first two zones in the present, and can travel through time by hitting signs labelled "past" or "future" and maintaining speed for several seconds.[6] By default, future stages depict neglect and decay after Robotnik has conquered Little Planet.[6] Players are encouraged to convert each zone into a "good future", with bright colors, no enemies, and few obstacles.[6] To achieve a good future in each zone, players must travel to the past—a primitive, overgrown landscape—and destroy a hidden transporter where enemy robots spawn.[2][6] The third zone is always set in the future, its timeline dependent upon whether the player destroyed both transporters.[1]

By finishing a level with more than 50 rings, Sonic can access a special stage, in which he must destroy six UFOs in a pseudo-3D environment within a time limit.[1][5] Time is reduced swiftly if the player runs through water, though a special UFO which appears when time is running out grants extra time if destroyed. If the player destroys all the UFOs before the time runs out, they earn a Time Stone.[4] Collecting all seven Time Stones, or achieving a "good future" in every zone, unlocks the best possible ending.[2] The game also features a time attack mode, where players can replay completed levels in the fastest time possible; a "D.A. Garden", where players can listen to the music of completed zones; and a "Visual Mode", where players can view the opening and closing animations.[7] The game also includes a save feature, which uses the back-up memory of the Sega CD.[4]:20


Sonic journeys to Never Lake, where an extraterrestrial body, Little Planet, appears on the last month of every year. Sonic's nemesis Dr. Robotnik has tethered the planet to a mountain and begun transforming it into a giant fortress with his robot army. Robotnik seeks the Time Stones, seven jewels capable of altering the passage of time. Sonic ventures into the planet, followed by the besotted Amy Rose, his self-proclaimed girlfriend.[b] Robotnik dispatches his top robotic enforcer, Metal Sonic, who kidnaps Amy to lure Sonic into danger. Sonic clashes with Robotnik and Metal Sonic and uses time travel to stop Robotnik and save Amy.

After racing and defeating Metal Sonic in Stardust Speedway and saving Amy, Sonic fights and defeats Robotnik in his base. Two endings exist, depending on whether or not the player collected the Time Stones or achieved a good future in each level. In one ending, Little Planet is returned to its rightful state and leaves Never Lake; in the other, Little Planet leaves Never Lake, but Robotnik uses the Time Stones to retake it. When the planet reappears at the lake, Sonic returns, determined to save it.


Sonic CD director Naoto Ohshima at the 2018 Game Developers Conference

The 1991 release of Sonic the Hedgehog, the first game in the Sonic series, was a major commercial success and positioned Sega as Nintendo's main rival in the console market.[8] Lead programmer Yuji Naka, dissatisfied with Sega of Japan's rigid corporate policies, moved with several members of Sonic Team to the United States to develop Sonic the Hedgehog 2 with Sega Technical Institute (STI).[9][10] Meanwhile, Sega planned to release the Sega CD add-on for its Genesis, and wanted a Sonic sequel that would demonstrate its more advanced features. Sonic's character designer Naoto Ohshima was Sonic CD's director; the remainder of the team comprised Sega staff who had developed The Revenge of Shinobi, Golden Axe 2, and Streets of Rage.[11]

The game was conceived as an enhanced port of Sonic 2 for the Sega CD. At this point, it was codenamed Super Sonic[12] and would feature additional levels, a fully orchestrated soundtrack, sprite-scaling effects, and animated cutscenes.[12][13] Meager sales of Sonic 2 in Japan and the team having its own vision resulted in the reworking of the port.[11][14] It was titled CD Sonic the Hedgehog first[15] before being renamed Sonic CD.[14] Sonic the Hedgehog had a balance on speed and platforming; STI built on the speed with Sonic 2's more focused level designs. However, Ohshima's team sought to focus on the platforming and exploration aspects. Art director Hiroyuki Kawaguchi, according to Eurogamer, "went all out" and created levels far more colorful than other contemporary games. The team built Sonic CD using the original's code as a base.[11]

Sonic CD marks the video game debuts of Amy Rose and Metal Sonic, both designed by artist Kazuyuki Hoshino. Amy had appeared in the Sonic the Hedgehog manga,[16] but was redesigned. Although Hoshino created her in-game graphics, many staff members contributed ideas to her design. Her headband and trainer shoes reflected Ohshima's tastes while her mannerisms reflected the traits Hoshino looked for in women at the time. Hoshino designed Metal Sonic in response to Ohshima wanting a strong rival for Sonic. Hoshino had a clear image of Metal Sonic in his mind from the moment he was briefed, and his design emerged after only a few sketches. The character graphics were created using Sega's proprietary graphics system for the Genesis, the "Sega Digitizer MK-III", featuring a bitmap and animation editor. The team mostly used Macintosh IIcis. Graphics data was stored on 3.5-inch floppy disks, which were handed to the programmer to work into the game.[17] Though Naka was not directly involved with Sonic CD, he exchanged design ideas with Ohshima.[18]

Ohshima cited Back to the Future as an influence on the time travel.[18] The developers designed four variants of each stage (one for each time period).[19] Ohshima hoped for the time period to change instantly with a "sonic boom" effect, but the programmers argued this was impossible and produced a loading sequence instead.[18] Sega did not pressure the team developing Sonic CD as much as the one developing Sonic 2. Ohshima felt this was because Sonic CD is not a numbered sequel; he considered it a recreation of the original game.[18] The total game data of Sonic CD is 21 megabytes (MB), compared to Sonic 2's 1 MB.[11] The game includes animated cutscenes produced by Toei Animation;[20] the team used a format that provided uncompressed imagery to the video display processor, which allowed for superior results in contrast to the Cinepak compression used for other Sega CD games.[11] The special stages feature Mode 7-like sprite rotation effects.[21] Time constraints led to one of the levels being cut.[19]

The Japanese soundtrack was composed by Naofumi Hataya and Masafumi Ogata, who had worked together on the 8-bit version of Sonic the Hedgehog 2. The game features two songs: "Sonic - You Can Do Anything", often referred to as "Toot Toot Sonic Warrior",[22] composed by Ogata and originally written for Sonic the Hedgehog 2, and "Cosmic Eternity - Believe in Yourself", composed by Hataya. Both are sung by Keiko Utoku.[23] The composition team drew inspiration from club music, such as house and techno, while Hataya cited C+C Music Factory, Frankie Knuckles, and the KLF as influences.[24]

Sonic CD was released in Japan on September 23, 1993,[25] and Europe in October 1993.[2] Sega of America delayed the game for two months to have a new soundtrack written and produced by Spencer Nilsen and David Young of STI, and Mark Crew; according to Nilsen, Sega believed it needed a more "rich and complex" soundtrack.[26] The tracks in the "Past" stages could not be replaced as they were sequenced PCM audio tracks rather than streamed Mixed Mode CD audio.[27] "You Can Do Anything" was replaced with "Sonic Boom", composed by Nilsen and performed by the female vocal group Pastiche.[26][28] The game was released in North America in November 1993.[29] Sonic CD was the flagship Sega CD game and the system's only Sonic game.[30] An enhanced version of the original Sonic the Hedgehog and a Sonic-themed localization of Popful Mail were canceled.[31][32]


Sonic CD was originally released for the Sega CD (seen here attached below the Genesis).

Two versions of Sonic CD were released for Windows: one in 1995 for Pentium processors, and another in 1996 for DirectX.[11] The Pentium version was only bundled with new computers and never sold in stores; Sega worked with Intel to make the game work properly.[11] The DirectX version was released under the Sega PC brand[33] and distributed by SoftKey in North America on July 8[34] and in Japan on August 9.[33] This version is mostly identical to the original release,[35] but loading screens were added[11] and it is only compatible with older versions of Windows.[36] Both Windows versions use the North American soundtrack.[11]

The 1996 Windows version was ported to the GameCube and PlayStation 2 in August 2005 for Sonic Gems Collection.[11][37] This port uses the original soundtrack in Japan and the North American soundtrack elsewhere.[38][28] The graphical quality was reduced to run properly on the GameCube,[11] but the opening animation is presented in a higher quality fullscreen view.[39]

In 2009, independent programmer Christian Whitehead produced a proof-of-concept video of a remastered version of the game, using his Retro Engine, running on iOS.[40] In 2011, Sega released this version as a download on Xbox 360, PlayStation 3, iOS, Android, Ouya,[41] Windows Phone,[42] Windows, and Apple TV,[43] with the Xbox 360, PS3 and PC versions ported by Blit Software The remaster features enhancements such as widescreen graphics, spin dash physics from Sonic the Hedgehog 2, both the Japanese and North American soundtracks, the ability to unlock Tails as a playable character, and achievement and trophy support.[44][45][46][47] Whitehead also designed two original stages, but they were excluded as Sega wanted to keep the game faithful to the original release.[48] The remaster was not released on the Wii as it exceeded the WiiWare download size.[49]


Reception (Sega CD)
Review scores
EGM9, 9, 8, 8[50][c]
Electronic Games92%[1]
Sega Magazine87/100[3]
Sega Pro90%[5]
Sega Force Mega85%[52]
Entertainment WeeklyA-[53]
Electronic Gaming MonthlyBest Sega CD Game of 1993[54]

Sonic CD received critical acclaim.[1][5][54] The Sega CD version sold more than 1.5 million copies, making it the system's bestseller.[55][56]

The presentation, visuals, and audio were praised. Computer and Video Games wrote that, although Sonic CD did not use the Sega CD's capabilities to its fullest, the game's graphics and sound were still excellent, calling the music "from the likes of 2Unlimited and Bizarre Inc".[2] Electronic Games said that the game looked similar to older games and used the Sega CD's special features minimally, but this did not detract from the quality. The music was singled out as making Sonic CD "stand above the crowd"; the reviewer wrote that it helped add richness to the game.[1] The reviewers of Electronic Gaming Monthly (EGM) praised the game's animated cinematics and sound, but noted frame rate drops during special stages.[50] Retrospective opinions of the presentation have also been positive. IGN praised its vibrant colors and felt the game looked nice,[57] and GamesRadar thought its music stood the test of time, writing: "What must've dated very quickly in the 1990s is somehow totally fresh today."[21]

However, some critics were divided over the change of soundtrack between the international and North American versions. GameFan, which had given the Japanese version a highly positive review, lambasted the change of soundtrack when Sonic CD was released in America.[26] GameFan editor Dave Halverson called the change "an atrocity that remains the biggest injustice in localization history".[58] The reviewer for GamesRadar claimed to have shut his GameCube off in disgust when he realized Sonic Gems Collection used the American soundtrack.[21] In a 2008 interview, Nilsen said "I think critics were looking for a way to bash the game... it was like we replaced the music for Star Wars after the movie had been out for a while".[26]

The gameplay was also widely praised. EGM admired the diverse levels and the ability to travel through time, which they felt added depth.[50] Electronic Games wrote that Sonic CD played as well as previous Sonic games, and that the time travel—coupled with large levels rich with secrets and Super Mario Kart-like special stages—added replayability.[1] Sega Pro noted the expanded environments and the replay value travel added by the time travel, writing that "the more you play Sonic CD the better it gets", but felt the game was too easy.[5] In its debut issue, Sega Magazine said Sonic CD was "potentially a classic", outshining the originality in the special stages and time travel.[3] GameSpot singled out the "interesting level design and the time-travelling gameplay" as a major selling point, saying it provided a unique take on the classic Sonic formula.[6]

Critics wrote that Sonic CD was one of the best Sega CD games. Electronic Games called it a must-have,[1] and Sega Pro said it was "brilliant" and imaginative and worth more than its price.[5] Destructoid described it as "a hallmark of excellence", creative, strange, and exciting, and stated that "to miss Sonic CD would be to miss some of the franchise's best".[59]

Reception to later versions of Sonic CD varied. GameSpot considered the 1996 Windows version inferior to the original Sega CD release, criticizing its poor technical performance and uninspired and monotonous gameplay. The reviewer wrote "those who have played Sonic on a Sega game system will find nothing new here" and that it was not worth its $50 price tag.[35] Reviews of the version in Sonic Gems Collection were widely favorable. IGN remembered it as one of the best things about the Sega CD and called it a standout for the compilation, stating it was a major selling point.[38] Sharing this position was Eurogamer, declaring: "Rejoice for Sonic CD... Just don't rejoice for anything else, because it's mostly rubbish."[60] According to Metacritic, the 2011 console version received "generally favorable reviews",[61][62] while the iOS version received "universal acclaim".[63] The game is frequently called one of the best games in the Sonic series and in the platform game genre.[64][65][66][67][68]


The story of Sonic CD was adapted in the twenty-fifth issue of Archie Comics' Sonic the Hedgehog comic book series. The adaptation featured some changes to the story, such as Tails being an important character and Metal Sonic having the ability to talk.[69] British publisher Fleetway Publications published their own adaptation in Sonic the Comic.[70] The final issue of Archie's comic, #290 (December 2016), also featured a retelling of the game's story.[71]

Two characters introduced in the game, Amy Rose and Metal Sonic, became recurring characters in the Sonic series. Metal Sonic later appeared as a major antagonist in Knuckles' Chaotix (1995),[72] Sonic Heroes (2003),[73] and Sonic the Hedgehog 4: Episode II (2012), whose story heavily connects to that of Sonic CD's.[74] Amy Rose has also gone on to become a character in many subsequent games as well, most notably in Sonic Adventure.[75] The game's animated sequences were included as bonuses in the compilation Sonic Jam (1997), and "Sonic Boom" was re-used as one of Sonic's themes in Super Smash Bros. Brawl (2008).[26]

To celebrate the Sonic franchise's twentieth anniversary in 2011, Sega released Sonic Generations, a game that remade aspects of various past games from the franchise. Both versions feature a re-imagined version of the boss battle against Metal Sonic.[76] The 2017 game Sonic Mania, produced for the series' twenty-fifth anniversary, features updated versions of Sonic CD's Metallic Madness and Stardust Speedway levels, including a boss battle against Metal Sonic.[77][78][79]


  1. ^ Japanese: ソニック・ザ・ヘッジホッグCD (シーディー) Hepburn: Sonikku za Hejjihoggu Shī Dī?
  2. ^ In the North American manual, Amy is incorrectly identified as Princess Sally, a character from Archie's Sonic the Hedgehog comic book.
  3. ^ EGM provided four scores from individual reviewers.


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External linksEdit