Tashistan is a city resembling that of a stereotypical Middle-Eastern city.
The Sonic Underground arrived in Tashistan after hearing that their mother's royal journals were rumored to be buried under a palace. When they arrived, the three split up. Sonia eventually ran into a boy named Raphi. This guy was fighting Dingo, and accidentally knocked said man very hard into Sonia, giving her amnesia. This ultimately resulted in her selling her Medallion due to not remembering its value.
Sonic and Manic attempted to locate Sonia by playing a song, which worked. Upon finding her, they got chased by Swatbots, and during the battle, Sonia regained her memories. She and Raphi were soon after kidnapped by Sleet and Dingo. Sonic and Manic, however, were able to sneak into the enemy base with the aid of some disguises, and were able to save Sonia. After that, they saved Raphi too, but not before his legs were partially roboticized.