Roseanne tries her hand at telephone solicitation while trying to console Becky who had an embarrassing accident in front of the school council.
Wily Kit and Kat are constructing a well for the New Cat's Lair on New Thundera. The Thundercats on New Thundera receive a distress signal from Thunderian refugees trying to find their way to New Thundera. The Kittens are left alone with Snarf on at the New Cat's Lair, and Lion-O and Snarfer are out constructing an early warning device (I guess for weather purposes). The rest of the Thundercats seek out the refugees in space. When Wily Kit and Kat strike water, they accidentally unleash a monster that Jaga trapped in the underground lake centuries ago. Frogman, with aquatic powers, tries to sink the New Cats Lair. Lion-O however re-traps Frogman in his watery prison.
The Ancient Spirits of Evil bring the Mirror Wraith to Mumm-Ra, and he disguises it as a child's toy. Mumm-Ra then intercepts a thunderian escape pod which carries in it a little girl. He gives the toy to the child (Leah), and leaves. She is rescued by the Thundercats, and goes into New Cat's Lair with the doll. The doll turns into the Mirror Wraith when left alone, and begins to destroy Cat's Lair, and the Thundercats have no clue where the evil Mirror Wraith came from.
Mario and Luigi disguise themselves as Riverboat Gamblers to rescue the Princess who is held captive on Captain Koopa's sidewheeler, "The Sinister Star".
Peggy wins a free health week with the healthiest man in Chicago, but ends up converting him to her lifestyle, and he drops dead.
Melody falls in love with a guest at the ranch. The gang helps her prepare for her date.
The Chipmunks overhear Dave suggesting that he would prefer Alvin to be a Gymnastic Pizza Twirler, Simon a Pogo Stick Tester, and Theodore an iguana trainer, and immediately start to pursue those careers.
A family of ghosts on vacation work to remove those they believe are interrupting their peace and quiet, including Peter, Winston and Slimer.
Beetlejuice needs some cash to buy Lydia a present so when she gets a job baby-sitting, he follows suit. But Neitherworld babies are a bit more of a handful than Outerworld ones, and Beetlejuice gets dragged before Judge Mental for a long string of offences. Can Lydia keep him from getting thrown to the Sandworms?
Sunni learns the importance of keeping Gummi traditions when a giant reawakens thanks to her carelessness.
Tummi takes pity on Doctor Dexter, an unsuccessfull pharmacist, and decides to improve his concocctions with a shot of Gummiberry juice. Unfortunately, this new wonder medicine also attracts the attention of Igthorn, and without the knowledge of how to exactly replicate the formula, the Doctor is caught between a rock and a hard place.
Kevin Keene and his dog Duke have been transported to Video Land and asked to help defeat Mother Brain.
The gang goes along with Scooby to his parents' house. Scooby's parents give him their heirloom, a special collar. Everything seems okay until the ghost of a long dead dogcatcher who was arrested when he tried to steal that collar off of a young Scooby comes to continue what he started years ago.
The Gestapo and the Italians plan to infiltrate the Resistance. Little do they know that René and friends are waiting for them.
In an attempt to find out who Kelly wants to take to a dance, Zack and Screech bug the girls' sleepover party and the girls get revenge.
After Screech gets struck by lightning, he gains the ability to see into the future, and Zack uses him to cheat on a mid term exam.
When Ganon learns that there is to be an Amateur Magician's Contest in the Castle of Hyrule, he sees his chance. He will enter the contest and use his powerful magic to disrupt it -- and, in the confusion, make off with the Triforce! Only Link and Zelda, in an exciting back-to-back battle with the forces of the evil Underworld, have a chance of stopping him!
After another earthquake caused by Mumm-Ra ruins the new Cats Lair construction site, the Thundercats go to see Jaguara and confront Mumm-Ra. Unfortunately, Mumm-Ra puts up a force field over entrance. Jaga appears to Lion-O and tells him to use the Eye of Thundera to get to Jaguara and the Gyroscope. Lion-O does so and battles Mumm-Ra, who throws him into the bottomless pit underneath the Gyroscope. Lion-O however, manages to throw his grappling hook to the top, which pulls him back up. Lion-O then shines the signal, which goes through the force field. All the Thundercats leap through the signal which takes them through the force field. Together, they fire all their weapons at Mumm-Ra and he is defeated. But before he leaves, he breaks the cord that holds the Gyroscope above the pit and it falls through. Now, New Thundera is literally falling apart. But Lion-O throws the sword in the spot where the Gyroscope used to be and calls upon the Thundercat Ancestors for help. The sword starts