The three Mother Boxes from the upcoming Justice League movie have been revealed. Warner Bros. officially kicked off their DC Extended Universe last year with Zack Snyder's Batman V Superman: Dawn of Justice, which introduced audiences not only introduced to the world's finest heroes but also teased the impending invasion by Steppenwolf. The story continues later this year with the filmmaker's Justice League, starring Henry Cavill as Superman, Ben Affleck as Batman, Gal Gadot as Wonder Woman, Ezra Miller as Flash, Jason Momoa as Aquaman, and Ray Fisher as Cyborg.

They come together in the upcoming film to battle Steppenwolf (Ciarán Hinds) and his army of Parademons, who have come to Earth in order to take back the Mother Boxes they had lost during their first war with Earth thousands of years ago (which will be the subject of the prologue sequence, featuring the Amazons, Atlanteans, and Humans fighting together). For those that don't know, the Mother Boxes are mystical, supercomputer-like devices created by the New Gods -- a race of beings from the planets New Genesis and Apokolips, the planet in which the supervillain Darkseid reigns supreme.

The Mother Boxes were also teased and revealed during the Justice League Comic-Con trailer, which showed the ancient humans burying their Mother Box in the forest, presumably after they had won their battle against Darkseid. Although we haven't yet seen the Atlantean or Amazonian Mother Boxes on-screen yet, Warner Bros. and DC Entertainment have presented them on the San Diego Comic-Con 2017 show floor. Screen Rant attended an exclusive early preview, where we snapped a few photos of each Mother Box. Take a look below.

At some point in the film, Dr. Silas Stone (Joe Morton) somehow attained the Human Mother Box (above) and, while attempting to figure out how to save his son, the Mother Box seemingly forges itself into Victor Stone, thereby turning him into the Cyborg. Recently, it was reported that the Human Mother Box no longer exists but rather has been fused into Cyborg; therefore making them one and the same thing; thus meaning that the Parademons would likely be coming after him moreso than the rest of the Leaguers.

It has been confirmed that Connie Nielsen and Robin Wright will be reprising their Wonder Woman roles as Queen Hippolyta and General Antiope, respectively, in the upcoming film, presumably during the opening prologue sequence in which the Amazons fought alongside the other two empires in defending Earth from Darkseid's army. Audiences should see them take their Mother Box (above) back to Themyscira for safe-keeping, which has been described as colored blood-red with ancient Greek text written all over it, thus making it the most impressive-looking of the three.

The last but not least Mother Box comes from the Atlanteans, which has been described as heavily matching the underwater aesthetic seen in Atlantis, the underwater kingdom ruled by Aquaman. Since it has been reported that Aquaman will return to Atlantis at some point in Justice League in order to retrieve his superhero costume, perhaps that's also when audiences will get to see their Mother Box on display -- aside from its presumed first appearance during Justice League's opening.

At this point, there's still quite a lot we don't know about the upcoming Justice League movie, which has recently been undergoing reshoots in London under the helm of Joss Whedon, who took over for Snyder after the director chose to temporarily step away from the project following a personal tragedy. The studio is expected to debut the newest trailer for the film during their Hall H panel at San Diego Comic-Con this Saturday, so be sure to check back for the latest DCEU news.

NEXT: WB Announces SDCC 2017 Movie Lineup

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