Sonic the Hedgehog CD (ソニック・ザ・ヘッジホッグCD?), or simply Sonic CD, is a platform game in the Sonic the Hedgehog series. It marked the first official appearance of the characters Metal Sonic and Amy Rose.
If you select the proper combination a secret sound test in Sonic CD can be found with text that reads: たのしさ∞ セガ・エンタープライゼス まぢん 画 (Infinite Fun Sega Enterprises Image by Majin)
- At the title screen, press Down, Down, Down, Left, Right, A. This will take you to the secret sound test screen.
- On the sound screen test, select FM No. 46, PCM No. 12, and DA No. 25.