Thundercats : The Return is a fan-made sequel to the original Thundercats series. It follows the adventures of Lion-O and the other Thundercats as they try to save their adopted home, Third Earth, from an onslaught of evil forces. The team must battle against Mumm-Ra, Slithe, Grune and other villains in order to protect the planet and its inhabitants. Along the way, they discover new allies such as Pumyra and Cheetara who help them in their quest. The series also features cameos from characters from other classic animated shows such as He-Man and She-Ra.