Darkseid may be the most iconic intergalactic threat to the Justice League, but he certainly isn't the only one. The DC universe is a big place, and there are plenty of cosmic threats for the JLA to take on. Despero is one such threat, and could be quite a formidable foe to the big screen Justice League. He's an intergalactic conqueror and the ruthless tyrant of the planet Kalanor. Aside from sporting one nasty appearance, Despero possesses incredible mental powers in addition to his tremendous strength and intellect. The third eye on Despero's head grants him powers of mind control, illusions, telekinesis, and telepathy. His physical powers even surpass those of both Superman and Shazam, as he draws his powers from the mystical "Flame of Py'tar", that gives him massive superhuman strength, durability, and the ability to alter his mass. In other words, he could easily hold his own against the JLA. Not only that, but he could be a great introduction to the bigger cosmic side of the DCCU, and somehow set up the future appearance of Darkseid. Plus, he would just look awesome on screen, and easily stand out as one of the most visually interesting villains in superhero cinema.