Darkseid has been one of the most powerful villains in the DC Comics universe, Batman v Superman: Dawn of Justice mentioned Darkseid’s existence through the years leading up to Justice League. He was originally supposed to be the Super villain in the Justice League movie until Steppenwolf served as the villain in the end.
In Batman v Superman: Dawn of Justice, Bruce Wayne has a dream where Earth has been taken over by Darkseid’s forces and Superman rules with an iron fist. The Justice League storyboards showed that the latest DCEU movie would have seen Darkseid successfully performing The Unity with the Mother Boxes, thus transforming Earth to resemble Apokolips. So it was confirmed that Darkseid did have a role to play in Justice League when director Zack Snyder was still overseeing it. Another interesting element of these storyboards is that the Hall of Justice archway is seen buried in the rubble following Earth’s transformation. Batman and the other Justice League members make Wayne Manor as the official Hall of Justice at the end of Justice League.
The other rumor is while battling Steppenwolf; Superman would have had a vision of Darkseid. Still, it’s good to know that at one point, Darkseid was going to be in the movie.
It was also reported that the movie was originally supposed to end on a cliffhanger, with Steppenwolf playing a “Silver Surfer role” and Darkseid playing a “Galactus role.” As of now, Justice League 2 has been postponed so unless Darkseid is a villain for a movie like Man of Steel 2, it’s possible we may not encounter him at all.
Justice League is now available on digital DVD.