This futuristiccity appears to be controlled by the monopolistic "HEXAeco" energy company, as a majority of the tall buildings and roadways are powered by them.
After his defeat at Ocean Palace, Dr. Eggman has fled into the city, has taken over the industry and is stealing their energy, so Team Sonic sets out to release it from his control. Team Dark realizes that the city must be crushed and be rid of the Doctor's robot army swarming the city (which would also free it). Team Rose continues to follow Amy on her quest to find Sonic, whom she correctly believes to be in the city. Team Chaotix must destroy all of the robots in the city on the orders of Eggman, meaning that Neo Metal Sonic took over the city instead, showing that it must have been a valuable asset to him.
The following is a list of requirements to attain a rank for each mission with each team.
Rescue the city under the control of Eggman!
Crush the city under the control of Eggman!
Stroll through the modern city!
Clear out the enemies in the city!
Get to the goal ring within 5 minutes.
Destroy 100 enemies (Time minutes.)
Collect 200 rings (Time minutes.)
Clear out all the enemies within 8 minutes.
This level precedes the Power Plant, which is one of HEXAeco's facilities.
The HEXAeco slogan is "Clean Power, Clean Energy".