Appellaxians

The Appellaxians were an alien race that sent several of its warriors to Earth to see who could conquer the planet first, as a means of determining who would become the new ruler of their home planet. Each alien warrior possessed a different power or ability, and attacked a different portion of Earth, which drew the individual attention of Superman, Wonder Woman, Batman, the Flash, Green Lantern, Aquaman, and the Martian Manhunter. While most of the Appellaxian invaders were defeated by the superheroes individually, the heroes themselves fell prey one by one to a single competitor's attack; they soon discovered that only by working together could they defeat the competitor. Afterwards, the group decided that they should form a permanent organization to confront menaces that required a similar pooling of resources, and dubbed themselves the Justice League of America.

Following an undetermined time since their defeat from the Justice League, the Appellaxians repented of their warlike ways. However, this shift in their culture created reactionaries in which one named Orkus led another invasion of Earth by using the planet as their battle form. But ultimately the Justice League once again defeated the rogue Appellaxians and returned them to their homeworld.