Third Earth

Third Earth is a fictional planet featured in the ThunderCats multimedia franchise. It was first seen in the multi-part pilot episode of the original ThunderCats animated series in 1985 and is the central setting for the entire series.

Description
Third Earth is the name attributed to the planet Earth of the distant future, which takes place long after the fall of modern society and is dominated by settlers from other worlds including the Ro-Bear Berbils, the Mutants of Plun-Darr and a small group of Thunderans.

One of the few surviving native inhabitants of Third Earth is Mumm-Ra, who is an undead sorcerer kept alive by the Ancient Spirits of Evil, who imbue him with great power and immortality in exchange for servitude. Mumm-Ra established his base of operations in the Black Pyramid, and from there, coordinated numerous schemes with his Mutant underlings to defeat Third Earth's off-world champions, the ThunderCats.