G's sword breaks during training so Randy takes him, Leo, and Debbie to S. Ward Smith to get it repaired, but run into trouble with a stanked Bucky and Flute Girl. Meanwhile; Ben, Gwendolyn, and Kevin try to find out what's wrong with Kevin's pet Zed when she feels down in the blues.
Broodwing makes the mistake of teaming up with the Sorcerer and ends up getting stanked. Randy tries to stop him. Meanwhile; Magica DeSpell manages to get an aging rune stone and winds up turning Sonic and Mike into babies, forcing Gwen and Zoey to care for them as Charmcaster trains Theresa into using magic.
The Deadly Six return to seek revenge on Sonic, they do it by stealing Cyborgs body, and kidnap Gwen. Sonic travels to the Lost Hex to save them. Meanwhile, the other resident put the 29 Anubian Baskurr puppies up for adoption.
GDN, Raven, and Zak Saturday reminiscent the time they met each other. Meanwhile, Sonic tries to moderate a peace treaty between the Mobians and Tetramands.
After destroying Slimovitz's car again; G ends up taking Slimovitz, Cyborg, Debbie, Kevin, and Rook to the Tetramand Homeworld to get a new car, but OTTO and Overload team up. Meanwhile; Max and Roxanne try to get each other gifts for aniversary presents, but Mesogog ends up attacking.
Spongebob, Mike, Randy, Sonic, Kevin, Owen, Mordecai, Rigby, Ben, and Danny enter a contest in order to win tickets to an Alvin and the Chipmunks contest, but it doesn't go well with their girlfriends since they have to do something very crazy. Meanwhile; Speedy Gonzales comes over to the mansion for a visit.
Trent and Lucy are nervous about going out on their first date so Ben, Kai, G and Debbie go with them. But the date interrupted by Nega Dragon and his new Monster. Meanwhile; Mikey and Rook Shim go to a museum and check out some interesting artifacts, but they find one that's desired by the League, and F.O.W.L. and get caught up in a battle of the villains.
Mordecai and Rigby must keep Thomas and Fat Tony hidden from Darkseid after the goat steals a bunch of weapons. Meanwhile; Ben, Sonic, and Randy send themselves to the world of Skylanders and must save it from Kaos.
Sonic and Flame start to bond with each other, but must save Gwen and Charmcaster when the Sorcerer stanks them. Meanwhile; Randy find a magical artifact and has to keep it safe from Magica De Spell.
Sonic, Gwen, Trent, Dudley, Sylvia, Kim, Ickis, Flame, Casey, April, and two new friends of theirs end up on a game show fighting against other planets, but learn that there's more then meets the eye.
Tails creates a robot that shoots out fireworks on New Years day at midnight, but Eggman converts it so that it shoots out mind control gas. Meanwhile; Ben and his Dimension 23 counterpart must save Kai from Nega Dragon. Also; Sonic meets his older brother who also turns out to be Charmcaster's boyfriend.
Ben becomes friends with Eggman's old intern Dave, but doesn't know that he's only being used to make a new Doomsday device. Meanwhile; Slowpoke Rodriguez is spending time with Speedy Gonzalez, making Winslow jealous of his roommates cousin.
When Erazor Djinn escapes from the Arabian Nights to get his revenge on Sonic the Hedgehog; the blue hedgehog sets out to find the World Rings which have appeared in the real world as well. Meanwhile; Gwen reunites with her ex boyfriend Trent and they bond as everyone else views a video of Sonic's first battle against Erazor Djinn.
Sonic accidentally uses a version of Chaos Control that causes him to switch bodies with his eleven year old self and he ends up teaming up with Past Tails, Chrono Spanner, and Wile E. Coyote while Past Sonic teams up with his future friends, Professor Paradox, and Amy Rose in order to undo the issue, all while trying to keep Eon from getting his hands on the Chaos Emeralds.
Max and Roxanne go on their honeymoon, but are forced to find a weapon by Lothor. Meanwhile; Shadow and Duncan pull off a con that upsets a bunch of mob bosses.
Max and Roxanne prepare to get married, but the festivities are interrupted by armies from Mesogog, Lord Hater, Betrayus, and Broodwing. Meanwhile; Spongebob and Speedy try to make a wedding cake after accidentally putting the original baker in a coma.
McFist puts the Deadly Six under his control, but ends up asking for Sonic's help when the Zeti's put the Robo Apes under their control. Meanwhile, Max Goof, PJ, and Bobby go to a temple in the Amazon to find some legendary treasures, but are followed by Venimus Snaptrap, his goons, Dudley Puppy, Kitty Katswell, and a whole mess of others.
When Sonic discovers that Mesogog has returned to seek revenge, he tells his roommates the time he met Mesogog and made the choice to permanently fight on the side of justice. Meanwhile; Mesogog discovers that Sonic's living in Toon City and plans an attack.
CatDog bring G, Debbie, Splinter, the Turtles, Rook Shim, Ben, and Kai to meet their parents, but are followed by Catfish Booray. Meanwhile; Bugs ends up watching over the entire Crimson Dragon Mall, but must get Top Cat's help when the Beagle Boys steal the deed to the mall.
During Sonic's birthday; Steelbeak and the Deadly Six manage to take control of Sonic's home city Station Square, forcing him to put an end to it. Meanwhile, while everyone is preparing for Sonic's birthday, many things happen; Top Cat and his gang hide out and steal all the food and Ben's mother Sandra Tennyson comes over for a visit.