Surely you have heard of Sonic the Hedgehog? SEGA's answer to Super Mario was all the rage back in the early 90s, and his adventures on the 16-bit Genesis console are still considered to be some of the greatest games of all time.
This game stands out, however, as it wasn't on a cartridge like the other Sonic games, but on a full-fledged CD-ROM (hence the name "Sonic CD"). That, of course meant more levels, crispier audio, and full-motion video! Sonic CD was a launch title for a short-lived add-on to the Genesis, called the SEGA-CD. In fact, it was the only game for that add-on to sell over 1,000,000 copies! Most Sonic fans say this was the greatest Sonic game ever made.
But enough babble, let's cut to the chase...
The gameplay is what you'd expect from a Sonic game: you collect rings, jump on robots to destroy them, nab powerups, and race to the goal. This game adds a twist: There are posts scattered around each level that take you to a past or future point in that level. You can go into the future for fun, but you really want to go to the past so you can find the Roboticizer and destroy it, so that you can ensure a good future for the level. It's one of two ways to unlock the game's good ending. The other way is to collect all the Time Stones (which replace the Chaos Emeralds in this game) in the Special Stage.
The graphics are vivid and very colorful. They make you feel like you're in the 90s again. The CD-quality music is really crisp; it's a mix of funky techno music that gets your heartbeat going fast. Depending on whether you have played the American version or not, however, you'll either love the soundtrack or hate it. All the music was changed for the American version of the game, replacing the aforementioned "funky techno music" with slower-paced easy listening. I'll leave you to be the judge of what soundtrack you ultimately prefer.
All this time I've been reviewing the SEGA-CDs version of the game; I need to get back on track here! The PC version of the game is also fantastic, especially considering that is was made for early Windows 95 computers. The music still sparkles, the graphics are still bright, and there's extra stuff as well, including the uncut version of the game's intro and ending (which was edited to meet the SEGA-CD's limitations), and hidden easter eggs. I should note that you'll need a special patch in order to play this game on newer operating systems such as Windows XP, but the version on this site comes packaged with the patch, to save you the trouble of having to find it!
Overall, Sonic CD is a real sonic boom! Not only is it one of the blue blur's finest moments, but also one of the greatest examples of the platformer genre.
NOTE: This is a ripped version of the game, and has no CD audio. I strongly recommend you grab the full game from the ISO cellar on the Abandonia forums.