How does sonic turn into darkspine sonic?

In the Sonic the Hedgehog series, Sonic cannot turn into Darkspine Sonic. However, in the game "Sonic and the Secret Rings," Sonic can transform into Darkspine Sonic by using the power of the Alf Layla wa-Layla, also known as the Arabian Nights. To do this, Sonic must collect 100 rings and then activate the Alf Layla wa-Layla by holding down the A button. Sonic will then transform into Darkspine Sonic, gaining increased strength, speed, and the ability to fly.