Chaos City is a city on Mobius in the Adventures of Sonic the Hedgehog television series. 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 favorite stuffed toy, Fuzzy Wuzzy, was left behind. Apparently, this event is what spurred Ivo Robotnik to become a villain later in life.