The hellish planet of Apokolips
Apokolips is a world first appearing in Kingdom Hearts Unlimited - Return of the Keyblade; though not actually visited in game, it is seen in cutscenes in the Midway City and Hall of Justice campaigns. An alien world ruled by the god Darkseid, Apokolips is a brutal dictatorship where Darkseid's word is absolute law. Though Darkseid is unopposed on his homeworld, he believes the Anti-Life Equation (allegedly the mathematical proof of the futility of life, which would give Darkseid complete mental control over all life in the universe) is hidden somewhere on the world of Earth-Prime. In order to obtain the equation, Darkseid has recently launched several campaigns against Earth, though he is opposed by heroes like the Justice League.