Chaos City

A city on Mobius in The Adventures of Sonic the Hedgehog cartoon show. Momma Robotnik had an old house located in Chaos City but moved when her son was still an infant. When the Robotniks moved, little Ivo's favourite stuffed toy Fuzzy-Wuzzy was left behind. Apparently, this event is what spurred Ivo Robotnik to become a villain later in life.

In the episode Momma Robotnik's Birthday, after her son had failed to defeat Sonic, Momma Robotnik concocted a scheme of her own to capture Sonic. She tricked Tails into going to Chaos City to the old Robotnik household to find Dr. Robotnik's long-lost Fuzzy-Wuzzy, where he was captured and used as bait to lure Sonic into a trap.