Review: Sonic CD (2011)


Every review of a Sonic game these days seems to start with a paragraph expressing dismay over how far one of gaming's biggest mascots has fallen. While the franchise has been on a slight upswing lately thanks to the release of Sonic Colors and Sonic Generations, Sega has decided to travel back into the past and revisit the series's glory days with a remastered version of the 1993 Sega CD cult classic, Sonic CD, available now for the Xbox 360, PlayStation 3, iOS, and Android, with PC and Windows Phone 7 releases also announced.

Updating a Classic for the Twenty First Century

Sega has previously released other classic Sonic titles such as Sonic 2 for many major platforms including Xbox 360 and iPhone, but these rereleases have been little more than ROMs bundled with emulators. For Sonic CD, Sega enlisted the help of hobbyist programmer and Sonic fan Christian Whitehead to bring the game to modern platforms. To accomplish this, Whitehead ported the game to a custom engine he wrote himself dubbed the Retro Engine, capable of perfectly capturing the look and feel of the original game while adding modern features. Unlike Sonic 4 Episode 1, this engine has wonderfully recreated the physics of the classic titles. Sonic runs, jumps, and rolls exactly how you would expect him to.

Small tweaks have been made to the game's presentation: rings now animate with twice as many frames as the original title; tricks used to fake transparency for things like the shield item have been replaced with real alpha transparency; players can choose to use either the original game's spin dash and physics or use the more famous Sonic 2 counterparts. The original game had two different soundtracks depending on whether you lived in America or the rest of the world, and this updated port allows you to choose which one you prefer. While the CD audio technology of the Sega CD caused music to fade out before restarting, music now loops seamlessly. The game runs at the proper aspect ratio of your screen rather than being stretched to fill wider aspect ratios, and also includes filters to smooth out the pixely look of the original game than can be disabled for purists. Special stages run much more smoothly than the original game, using proper scaling techniques on the UFOs and maintaining a constant 60 frames per second. Upon completing the game once, players can choose to play as Tails, who was not featured in the original game, complete with new animations made specifically for this port. All the unlockable secrets of the original game are intact, such as the D.A. Garden, and a new secret has even been added.

In general, the game has been nearly flawlessly remastered for modern consoles while maintaining the feel and style of the original version.

Warp Speed

Sonic CD has always been a bit of an oddity among Sonic games. Developed parallel to Sonic 2, it focuses far more on platforming and exploration than later titles. The primary gimmick of the game is a time-travel mechanic, allowing you to go either backwards or forwards through time in each level, complete with different art and music for each time zone. To do this, you must search for a sign labelled "Past" or "Future" and then build up speed for a few seconds, at which point you will warp. By default, you can either go into the past or into a "bad future", where the level has decayed greatly and been warped by Dr. Eggman's machines. To create a "good future" with bright colors and no enemies, you must travel back into the past and search for a generator to destroy in each act in order to change the course of history. Alternatively, you can play through the usual special stages accessed by collecting fifty rings and jumping into a giant ring at the end of the stage. By completing all the special stages and earning all the Time Stones, you can automatically create good futures in every stage.

Consequently, the level design for the game is very different than Sonic 2 or 3, more closely resembling the original Sonic title. Levels are designed to allow you to backtrack and hunt around in search of time travel signs and generators, and there are far more obstacles designed to hinder your speed and make it trickier to build up enough velocity to time travel. Many players may find this frustrating; the fifth level, Wacky Workbench, is particular irritating to navigate due to floors that instantly bounce you far into the air should you touch them. I usually choose to play the game as a more traditional Sonic title, trying to simply reach the end of the level and use Time Stones to unlock the good futures rather than exploring the past in search of generators. Exploration is simply too frustrating and unrewarding.

Special stages in Sonic CD are done in a Mode-7 style sort of 3D. You have to run around a course and jump into six moving UFOs; hitting all of them within the time limit earns you a Time Stone. There are obstacles on the course to slow you down or send you in the wrong direction, and running on water subtracts from the time limit. The special stages in this new port are incredibly improved compared to the original Sega CD versions, which were choppy and made it difficult to judge the distance between you and a UFO in order to jump into it. Even now, however, the hitboxes for the UFOs feel somewhat off and the stages can prove to sometimes be an exercise in frustration, particularly starting with the fifth one.

Sonic's moveset is largely the same as in Sonic 2. You can run, jump, and roll, as well as spin dash. There are two spin dash modes; by default, it functions as it did in Sonic 2, but you can optionally enable the spin dash used in the original Sonic CD, which requires more charge-up time. Enabling the Sonic CD spin dash also enables the original game's camera, where the camera pans when you are running at high speed to enable you to see ahead further ahead and react to obstacles more easily. Unique to Sonic CD is a move known as the Super Peel Out, performed by holding up and tapping the jump button. It functions similarly to the spin dash but does not cause you to roll, resulting in higher velocity at the cost of vulnerability. Essentially, the controls are fine, even on touch screen devices. If you've ever played a classic Sonic game, you should know what to expect.

Boss fights in the game are fairly easy, even by Sonic standards. Each boss has its own separate, short act set in the "future" form of each level. Whether the future is good or bad depends on whether you destroyed the generators in the level's two previous acts (or have all the Time Stones). Generally, the fights are not difficult and often only take one hit to destroy, meaning most of the fight consists of dodging attacks rather than trying to land your own. One boss even destroys itself, making the battle entirely about surviving until the end.

There is also a time attack mode available, which removes the time travel mechanic from the levels and challenges you to complete them as quickly as possible. The game's unlockables are tied to this mode; getting your total time under certain milestones unlocks secret content like an interactive music player and a mode to view the game's opening and ending animations. There are also secrets hidden within some of those secrets; I recommend playing around in the sound test if you want to find them.

Overall, the game's enjoyability comes down to its level design. The levels are a mixed bag, ranging from annoying (Collision Chaos, Wacky Workbench) to amazing (Quartz Quadrant, Stardust Speedway). It usually never gets bad enough to make you want to stop playing, but in general the design is less consistently fun than other titles.

Toot Toot Sonic Warrior

Sonic CD is well remembered for its soundtrack, due to its origins on the Sega CD. Rather than being synthesized like most 16-bit titles, Sonic CD made use of full CD audio, resulting in high-quality recorded music rather than chiptunes. When the game was released in America, Sega also recorded a second alternate soundtrack specifically for the local release. Both the original Japanese and American soundtracks are available in this port. While the Japanese soundtrack was upbeat and frantic with lots of small vocal samples and jazzy instruments, the American one is more subdued with layers of guitar and synth pads. I personally prefer the Japanese soundtrack, but having the option available is a major plus. One disappointment, unfortunately, is that the vocals in the Japanese opening and ending tracks have been nixed due to licensing issues; the vocals for the American track, Sonic Boom, are completely intact. Unlike the original game, the music now loops correctly rather than fading out and restarting in the middle of levels. As a whole, the soundtrack is as strong as ever.

Visual Mode

Sonic CD has a very unique visual style, focusing on much more surreal environments than other titles in the series. Many of the levels are based on those in Sonic 1; Green Hill, Spring Yard, Labyrinth, Star Light and Scrap Brain are all reprised in alliterative acts named Palmtree Panic, Collision Chaos, Tidal Tempest, Stardust Speedway, and Metallic Madness. Two levels - Wacky Workbench and Quartz Quadrant - are more original. Quartz Quadrant and Stardust Speedway are particularly visually stunning, with bright color palettes and interesting artwork. The artwork in each level also changes depending on the era you are in; good futures are usually brighter, but some of the bad futures are visually striking as well. In terms of art style, Sonic CD is definitely a highlight of the 16-bit era. The game also runs in the proper aspect ratio of whatever system you are playing on, so if you have a 16:9 TV (which you probably do) the game runs in real widescreen, rather than being stretched or running in a box as emulated titles do.


This updated rerelease of the game also takes advantages of modern gaming luxuries like leaderboards and achievements/trophies. It supports Xbox Live and PlayStation Network as well as Game Center on iOS, but the Android version is sadly lacking in any online connectivity or achievements. On the XBLA and PSN versions of the game, there are also three filtering options available to clean up the pixely look of the original game's art. "Sharp" is akin to hq2x filters used in most emulators, but looks a bit cleaner here due to superior implementation. "Smooth" is a simple blur filter, and "nostalgia" disables filters completely for a more authentic 16-bit experience. Mobile versions have no filtering at all.

As mentioned, Tails is also unlockable upon completing the game once. He plays as you would expect, lacking the Super Peel Out but making up for it with the ability to fly. New artwork for Tails has also been made, since he was not in the original game. Special stages in particular use an entirely new set of sprites. When playing as Tails, however, achievements are disabled, Amy is not present in levels, and the opening and ending animation sequences are omitted. Regardless, it's a nice little extra to have and shows that Sega put in much more effort with this rerelease than most developers would (or even themselves, usually).


Sonic CD is a cult classic for a reason. It's visually exciting, the music is fantastic, it has a unique gimmick, and most of all, it's just fun to play. Sega and Christian Whitehead have done a fantastic job bringing it to modern platforms, and deserve praise for putting in far more effort than the usual "ROM and emulator" treatment most games get. If you're a fan of classic Sonic games or 2D platformers in general, I'd recommend picking it up for only $5 on PSN, 400 MSP, or $2.99 on mobile.

Score: 9.0


- Fantastic porting job by Sega and Christian Whitehead

- Great artwork and soundtrack

- Lots of replay value in exploring levels and time attacking


- Some frustrating level design

- Lacking vocals for the main theme songs of the Japanese soundtrack

- No achievements or leaderboards on Android

(Caution to Android buyers: Some people, including myself, have experienced difficulty downloading the game data after installing. If you are patient, the game will eventually download, but it may take quite some time. If you have a friend with the game or can find the data files on the internet, you can simply copy the data from their SD card or phone to yours to play the game. This still requires a purchased copy from the Market, of course.)