Sonic CD is a platform game developed by Sega for the Sega CD in 1993. It is the third installment in the Sonic the Hedgehog series and was the first to feature time travel. Sonic CD was a pioneering step in the Sonic franchise, introducing several new elements that would become staples in later games.

The game featured a unique level design that allowed players to travel through time. By entering a special stage, players could travel to the past or future versions of levels, which had different layouts and enemies. This allowed players to explore different paths and find secrets. Sonic CD also introduced the Super Peel Out, a move that allowed Sonic to quickly accelerate to high speeds.

Sonic CD also featured some of the most impressive graphics seen on the Sega CD. The game featured pre-rendered 3D backgrounds and sprites, as well as animated cutscenes. The soundtrack was composed by Naofumi Hataya and Masafumi Ogata, who created an iconic score that has become a fan favorite.

Sonic CD was a major step forward for the Sonic franchise. It introduced innovative level design, new moves, and impressive graphics. It also featured a memorable soundtrack that has become iconic in the gaming world. Sonic CD was a pioneering step in the Sonic franchise and helped set the standard for future games in the series.