The Lunataks were a group of six very powerful and evil beings from the moons of Plun-Darr in the 1985 Thundercats series. Lunataks were feared by the Mutants, who were native to the nearby planet Plun-Darr.
At an undetermined point in the past the group made their way to Third-Earth, where they engaged Mumm-Ra in battle. Mumm-Ra managed to defeat the Lunataks and imprisoned them in a volcano.
After Mumm-Ra was seriously injured at Fire Rock Mountain after exposing himself to the power of the Star of Thundera, he decided he needed new, stronger allies to defeat the Thundercats. With the assistance of Ma-Mutt, Mumm-Ra had the mutants free the Lunataks from their volcano prison and convinced them that they all had a common enemy in the Thundercats.