This one was partly a Cheetara origin.
It follows her trying to join up with the clerics coven, but fails as she proves to lack patience.
Although a Cheetara origin, it's told through the eyes of Tygra and explores his feelings for her.
In the present, Lion-O uses his recently mastered Sight-Beyond-Sight technique to seek out the stone only to find...
The traitorous Grune!!
He himself is seeking the stone but finds the inquisition of the forgetful elephants a difficult task.
The cats fall back and play it stealthy.
Until Kit blows their cover.
"Heeey! It's Kit! And look, you've brought Lion-O and your friends!"
Busted. Drop your weapons.
Thundercats be packing!
After threatening the elephant people, Lion-O not only tells Grule of where he can find the stone, but shows him by opening the gate to the Astral Plane. But then...
Thunder. THUNDER. THUNDER!
After making quick work of Grune and his forces, Tygra and Lion-O have some strong words before they themselves enter the Astral Plane to seek the stone.
Before following his elder brother in, Lion-O is warned of a vision involving a great betrayal at the hands of Tygra .
While stalking them, Mumm-Ra monologues in crow form. He boasts about being a master of his domain in the Astral Plane.
And follows the cats in! The End.