Robotnik decides to cripple Mobius' three major transit systems: Rail, Air, and Sea in order to fully gain control of the planet. Sonic has to circumnavigate the planet in order to save the day.
Robotnik invents a giant AMNESIA RAY in his booby-trapped PINBALL FORTRESS (based on the Sonic game per Roger Hector) in order to erase the bad memories the Mobius citizens have of him, and make them think he's a great guy.
A female space hunter named Katella, who is capturing animals all over Mobius for a Zoo, teams up with Robotnik and captures Sonic. To Robotnik's great fear, she then plans to marry the eggman!
Sonic plays Cyrano to bring Robotnik Jr. and Breezie together. The problem is, Breezie's crazy about Sonic. So Sonic gets out of the way, but when he does, Junior is captured by Robotnik, and Breezie comes to the rescue, finally falling for him.
When Wes Weasley returns to the Fortress, Coconuts tricks Robotnik into signing an IOU so he can buy thousands of Mobiums worth of magic tricks to use on Sonic. In the end, Sonic goes free, and Robotnik is forced to pay Wes the massive IOU debt.
Brandon Quark, an evil half-man, half-duck genius challenges, then teams up with Robotnik to capture Sonic. But Sonic knows their weakness, and pits the Badnik geniuses against one another, and sets himself free.
Robotnik pretends to retire, and lures Sonic and Tails into a phony vacation resort, laden with booby-traps set by Scratch and Grounder. But Sonic takes the bungee jumping, hang gliding, and skydiving in stride, and gives the bashes the bots.
Santa Claus has made an announcement - he is retiring and has picked the perfect successor - "Robotnikclaus"! Sonic and his sister resolve to persuade Santa to return and set Christmas straight. When the two track down the Santa who made the announcement, they discover he is just a phony robot and the real Santa Claus is being held prisoner.
When Tails gets trapped in the "Warp of Confusion" (an Escher-like world of another dimension) by Robotnik's cousin, Dr. Warpnik, Sonic comes to the rescue and traps Robotnik and his badniks in the warp.
In order to free Sketch Lampoon (a satirical comic book artist) from Robotnik's new high security prison, Sonic allows himself to be captured, then makes a high speed rescue and escape.
Santa Claus has made an announcement - he is retiring and has picked the perfect successor - "Robotnikclaus"! Sonic and his sister resolve to persuade Santa to return and set Christmas straight. When the two track down the Santa who made the announcement, they discover he is just a phony robot and the real Santa Claus is being held prisoner.
Sonia is invited to a debutante ball, but before she can be officially announced to society, she and her brothers, Manic and Sonic have an important mission.
As Sonic begins to chow chili dogs for a snack, he finds a message in the sack from his mother urging him to head to Speedster Island.
Sonic and The Freedom Fighters journey to Robotnik's underground air base in a mission to reprogram the launch data on Robotnik's fleet of Stealth-Bot aircraft. While attempting to reprogram the Stealth-Bot computer system.
Sonic attempts a solo rescue to prevent prisoners from being roboti-sized and is hit by a Memory Scrambler that erases short-term memory.
After Antoine saves Sally's life during a raid, Sonic can't stand his bragging and zips in to see Uncle Chuck, who finds out his "bug" in Robotnik's HQ is malfunctioning.
Santa Claus has made an announcement - he is retiring and has picked the perfect successor - "Robotnikclaus"! Sonic and his sister resolve to persuade Santa to return and set Christmas straight. When the two track down the Santa who made the announcement, they discover he is just a phony robot and the real Santa Claus is being held prisoner.
Robotnik severely upsets the ecosystem above and below the surface, when he sends explosive, Robotnik snake probes drilling deep under ground in search of oil lakes.
The Freedom Fighters, with new addition, Dulcy, develop a De-Roboti-sizer and try it out on Bunnie. It's a success and, against Sally's wishes, Sonic battles Robotnik's newest weapon, a Virtual Reality Shriek-Bot.
When Sally uncovers Robotnik's plan to seed the cloud with toxic rain, they attempt a daring mission to sabotage the dirigible-like craft being transported by land vehicles. Mission fails when Sally, Bunnie and Antoine are captured.