At one point, while on the other side of Mobius, Sonic attempted to get to Robotropolis quickly using the Cosmic Interstate, which lead him to the parallel universe of Anti-Mobius (now called Moebius). During his brief time in this realm, Sonic encountered his alternative self, Evil Sonic. Although he quickly defeated his evil double, and was able to get back to his home realm, Evil Sonic would continue to pose a threat to his reality in the future.
Traveling across the Cosmic Interstate, Dr. Nega's actions caused severe chaos across the multiverse. For this reason, the Zone Cops issued a lockdown on the various universes, leaving only a few open to maintain stability. Nega's war with the Zone Cops resulted in massive damage to No Zone. Because of this, the Zone Cops were too preoccupied making repairs to deal with the Suppression Squad's invasion of Mobius Prime.
Sonic X Zone