Even superheroes sometimes cannot cope alone with a global threat. Here is with Superman and Batman have led the team the strongest, most powerful fighters for the benefit of mankind.
Heroes once opposed each other, between them were historical differences, but when the villain, attack on calm throughout the Galaxy, it becomes clear that we should fight against it with one voice.
So, the main antagonist in the History of superheroes alike "Justice League: part 1"-the ruler of Apokolipsa-Darkseid, whose own planet becomes a little to realize ambitious plans for world domination.