Wilykit and Wilykat meet a traveling Wolo and then go in search of a piece of stolen jewellery. Lion-O also takes the ThunderTank for a short-lived joyride, whilst Tygra looks for Thundrylium in a strange cave and begins to age at an accelerated rate. Willa, of the Warrior Maidens is introduced, and she and her sister, Nadya, manage to fight off Monkian but both of them are cautious of the new arrivals (i.e. The Mutants are looking for a "feminine touch" around Castle Plun-darr and attempts to capture natives of the 3rd Earth.
RA ON THUNDERCATS CARTOON FREE
Lion-O meets the Unicorn Keepers and then sets out to free Snarf from his captors. Snarf is captured after freeing a unicorn from the pirate Hammerhand and his Berserkers who are out hunting for food.
Mumm-Ra disguises himself as a Thunderian named Pumm-Ra, and claims to have rescued Cheetara from the mutants in order to infiltrate the now completed Cat's Lair. After learning more about the Brute Men from the Berbils, Tygra tells the twins to stay behind, as the adult ThunderCats rush off to free these peaceful creatures. The Cats Lair is nearly complete when an agitated Wilykit and Wilykat rush home to tell the other ThunderCats that the Mutants have enslaved a race of creatures called Brute Men to build their new fortress, Castle Plun-darr. They soon learn that the Berbils are being frequently attacked by the Trolligs who steal their fruit to give to the Giantorrs. Later, Lion-O and Snarf are taken prisoner by a band of small robotic bears named Ro-Bear Berbils, lead by Ro-Bear Bill and Ro-Bear Belle. Panthro introduces the ThunderTank, saving the others from a meteor shower conjured by Mumm-Ra that buries the remnants of the ThunderCats' ship. With the young Lord of the Thundercats in sight, Lion-O is about to face his toughest enemy yet. While exploring Third Earth, the Mutants ship, piloted by Slithe, Monkian and Jackalman, is brought down by a mysterious black pyramid which is the home to Mumm-Ra, an evil demon who is willing to form an alliance to capture the Eye of Thundera. With the others forced into sleep capsules, Jaga must pilot the ship for the world known as Third Earth and Lion-O, just a young boy, must learn what it means to become a man and Lord of the Thundercats as he learns to wield the power of the Sword of Omens. Their journey changes when an enemy force known as the Mutants attack and leaves their ship severely crippled.
The ThunderCats must find a new home after their home planet, Thundera, explodes.