Dr. Robotnik organizes a bounty hunters convention to capture Sonic but when it doesn't go to plan, Robotnik builds Scratch and Grounder to be part of the new Super Special Sonic Search and Smash Squad (or SSSSS Squad for short).
Desperate to get workers to build a Robotnik statue, Dr. Robotnik opens Casino Night Zone with his pal Smiley but when Sonic stops Scratch and Grounder, Robotnik traps Tails so Sonic has to make a choice to save his pal.
While Scratch and Grounder try to catch Sonic using a Suction plate, two aliens, one being a prince, crash lands on Mobius. Sonic meets the prince when he finds out that the prince's baby brother would blow up Mobius which Sonic must save.
Robotnik's momma escapes from the home for mothers of villains and demands her birthday present! When she endangers Sonic and Tails, and they manage to have her taken back to the home, even Robotnik is glad to see her go.
Coconuts is exiled by Robotnik to a remote jungle, where he uses a giant baby ape to destroy villages. But Sonic exposes Coconuts as a robot, and the baby ape's real Dad takes Coconuts and the baby ape away for a spanking.
Dr. Robotnik with help of a tied up professor invents Gismo Gas that makes objects larger; while Sonic and Tails are in Weiner-Ville eating chili-dogs the machine explodes causing Tails to become a giant which Sonic must find the cure.
Tails adopts a cute and fuzzy pet named Walter who turns out to be a black hole who sucks up everything in Mobius. Realizing that Walter is from another dimension our heroes have to return him and they soon find themselves spinning through interdimensional limbo.
Sonic leaves Tails in charge of protecting a squirrel village food supply, when he zips off to stop a dam from breaking. Robotnik sends Scratch and Grounder after Tails, who defends himself the best he can with "Home Alone" booby traps for Scratch and Grounder. When Tails is finally caught, Sonic speeds back to save him.
When Robotnik invades Labyrinth, an underwater city, and kidnaps Princess Bubbles, a seahorse-dude named Surff seeks Sonic's help. It seems Surff and the Princess are in love, but the royal family deems Surff "unworthy". Sonic, Tails and Surff must avoid the undersea traps and Mobius sea monsters while Sonic rescues the Princess and reunites her with Surff -- making it look like Surff did the whole thing.
Robotnik invents a ray that ages people but when Sonic and Tails are having free samples in Robotnik's Food Factory, Grounder presses the wrong button that turns Sonic, Tails and by mistake Robotnik into babies.
Robotnik plans to block out the sun and extinguish all life and nature on the planet Mobius. Then he creates a robot son and tries to train him in the ways of wickedness. But when Robotnik Jr. meets Sonic, he becomes a naturalist and teams up with Sonic to thwart Robotnik's evil scheme.
Robotnik invents an electron altering generator which makes Scratch and Grounder twice as fast as Sonic. When they lose it and Tails picks it up, Tails speeds through the Mobius countryside leaving disasters and accidents in his wake. Seeing this, Robotnik convinces the villagers that the little fox belongs in jail, and Tails is forced to flee. With Tails all alone, Scratch and Grounder attack, and Sonic makes a last minute rescue.
Robotnik captures a Kangaroo named MacHopper, and uses his "brain-wipe-reprogramming-computer" to transform him into a resourceful demolitions expert (Ala MacGiver). But Mac escapes before Robotnik installs the final "Get Sonic" program, and teams up with Sonic and Tails to BLAST Robotnik.
When S and G rocket to outerspace to mine a radioactive mineral from asteroids, Sonic and Tails stow away. Through a blunder by the robots, all are stranded in space, and Robotnik tries to blow all of them out of the stars. Sonic builds a rocket out of S and G's spare parts, and all return to Mobius.
When a Rebel Base is threatened by Robotnik, Sonic and Tails team up with Big Mike and Da Bears to run a booby-trapped gauntlet in their gigantic Road Warrior-like truck, breaking through every obstacle S and G put in their way until they save the rebels.
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.
When Dr. Robotnik plans to change the Sonic 12 Mobium bill to a Robotnik one, a salesman comes and offers magical items but Robotnik throws him out causing Coconuts to have an idea to catch Sonic using the salesman's goods.
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 Tails invents a Hover-Hanglider for Sonic's birthday, Sonic suggests he assist Prof. Von Schlemmer with his new Robotnik-Nabber machine. Robotnik hears about this, and poses as Von Schlemmer to trick Tails into inventing a Sonic-Nabber instead. Sonic must use the Hover-Hanglider to rescue Tails and the Prof., and destroy the Sonic-Nabber.
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! In an attempt to stop the ceremony, Robotnik accidentally frees Sonic, who poses as a minister and sees that the ceremony takes place as scheduled.
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. Sonic teams up with Sgt. Dobermann, and Wes Weasley (who sold Robotnik the booby-traps in Pinball Fortress) to destroy the ray.
Robotnik invents a robot coach -- the "Coachnik", to put S and G through a "Training Camp" to improve their skills. Then Coachnik puts a bomb in Grounder's head as a booby trap for Sonic, and a football game ensues with Grounder's head as the ball.
When outlaws chase a sheriff out of a western town, Sonic takes over. But the outlaws are robots built by Robotnik. And when they capture a pretty possum of a saloon girl, Sonic meets Robotnik for a showdown.
First in a four-part Time Travel series. Robotnik invents a time machine to go back in time and gather four powerful gemstones. His first attempt is on the high seas, but Sonic goes into hyper-Sonic-overdrive, and reverses time to go after him. Robotnik finds the gem stone in a buried treasure, but loses it again and is forced back to the future by Sonic.
Part two in the four part series. Robotnik goes back to medieval times, and enlists the help of Merlink the Magician to get his magical gemstone. But first he must defeat Sonic (in blue armor) in a jousting tourney. Sonic is victorious, and is knighted by King Arfer (a dog) before he forces Robotnik into the future again.
Part three in the four part series. Robotnik timetravels back to Mobigypt, makes himself a pharoah, and enslaves everbody in an effort to find the gemstone of immortality. Sonic and Tails follow after him, and have to chariot race him, then search "Indiana Jones-Style" in a pyramid for the gem, before sending Robotnik back home.
Number four in the four part series. Robotnik learns that the most powerful gemstone -- able to create life itself -- is located in Prehistoric Times. So off he goes again, followed by Sonic and Tails. When he arrives, Robotnik turns dinosaurs into robosaurs, and Sonic has to lead the Cave dwellers in a "football team" defense of the gemstone located at the top of a volcano. In the end Robotnik fails again, and Sonic boots him back to the future, then destroys the time machine once and for all.
Robotnik shrinks Sonic and Tails with a shrink ray and puts them into his terrarium. Sonic and Tails escape on the back of a gecko, reverse the shrink ray to restore themselves to normal, then use it to shrink Scratch and Grounder, and put them down Robotnik's shirt.
After Robotnik finds out that it is Sonic's birthday, Sonic is bored until someone gave him a ticket to Mobiusland (a theme park). However Robotnik took over and it got changed to Robotnikland which Sonic must enjoy his present.
Robotnik lures Sonic into a round-the-planet vehicle race called the Mobius 5000 by threatening to foreclose on a loan to an orphanage. Sonic's only way to save the orphanage is to enter the race himself, and win the M10,000 Mobiums prize money. Things get rough for Sonic when Robotnik's three deadly racerbots try to run him off the road for good! But in the end, Sonic wins the race, saves the orphanage, and gets a contract from Hensoil.
When an undersea world is threatened by Captain Memo and his lobster sub, Sonic spreads a rumor that Memo plans to attack Robotnik next. When Robotnik hears of it, he launches an attack on Memo with a Shark-shaped sub, but Sonic's plan backfires when Robotnik decides that he will conquer the undersea world himself. With the help of a friendly school of porpoises, and the Mer-People of the undersea world, Sonic sends Robotnik and Memo floundering away.
Sonic loses his memory when Robotnik uses a hypnotic flower pollen on him, and tells him he's just an "ordinary" guy. With Tails trying to remind him who he is, Sonic joins a Hog Biker gang and hits the open road. Tails finally catches up with him and manages to remind Sonic who he really is. In retaliation, Sonic leads his Biker Buddies in an attack on Robotnik.
Scratch and Grounder build their own robot, a naive over-grown kid called "Robot". When Robot runs off with Robotnik's new invention, the Super Planetary Implosion Module (SPIM), capable of impoding huge parts of Mobius out of existence, the race is on to catch him, over all kinds of Sega terrain; mountains, caves, lava pools, rivers, oceans, snow and ice. Robot's homing device leads him back to the Fortress, but before he can press the button on the SPIM, Sonic and Tails rewire it to make the Fortress implode into the size of a shoebox.
When Sonic vanishes mysteriously, Tails enlists the help of a bi-plane pilot named William Le' Duc, and Professor Von Schlemmer. With the Professor's "Sonic Sonar", they are lead to the Mobius Jungle and a Mayan temple appears out of thin air. It is a magical cursed temple which only appears at night, and Robotnik has locked Sonic inside it. Tails and friends have to pass through the perils of the ancient temple and save Sonic before daylight, or all will be trapped forever.
Wes Weasley has sold out to Robotnik, and lures Tails, Sonic and all of their friends to a yacht under the guise of a "Hero of the Year" ceremony to thank Sonic. Once everyone is aboard, Robotnik and his badbots take over the ship and threaten to sink it unless Sonic surrenders. Sonic is locked in an undersea cell, and Robotnik orders the yacht with Sonic's friends sunk anyway, but just before that happens Wes Weasley has a change of heart and comes to the rescue. Robotnik meanwhile is giving himself a testimonial dinner, but Sonic ruins the party.
Lazy con-man Bo Beagle has the Choas Emerald ring stuck on his finger, and Robotnik wants it for one of his evil schemes: to use the emerald to sink the continent of LABYRINTH into the sea. Sonic is forced to protect the irritating Bo, until they can get the ring off his finger, and hide it where Robotnik will never find it.
Throbbin Screech brings a TV crew to interview Robotnik for "Lifestyles of the Sick and Twisted". Robotnik rampages through the Mobius countryside proving how sick and twisted he is, and Sonic is kept busy doing rescues. Tails decides to take on Robotnik himself, but is captured. But Sonic comes to the rescue in a Coconuts disguise, rescuing Tails, and being interviewed by Throbbin for "Lifestyles of the Brave and Do-Gooders".
After a failed chili-dog trap, Scratch and Grounder find an old martial arts teacher which Robotnik kidnaps and uses his knowledge to create and turn Scratch and Grounder into Robo-Ninjas to stop Sonic.