"Batman v Superman: Dawn of Justice" had plenty of hints indicating that "Justice League: Part One" would introduce Darkseid as the main villain. However, according to El Mayimbe on his new show Heroic Insider, Darkseid might not appear until "Justice League: Part Two" and that the first film will focus on a war with Atlantis.

According to the report, Batman (Ben Affleck) and Wonder Woman (Gal Gadot) will begin searching for the other powerful beings such as Cyborg (Ray Fisher) and the Flash (Ezra Miller). However, when it comes to recruiting Aquaman (Jason Momoa) and the rest of Atlantis, negotiations will not go smoothly and a war will take place.

El Mayimbe further explained that Wonder Woman and Aquaman will already have some sort of feud between them, explaining that the Atlanteans and the Amazonians have not had a good relationship for years and this will transfer to their respective heroes. 

In the report, Mayimbe also revealed that Batman will be using a Bat submarine in order to travel deep under the sea. This will be the third vehicle introduced in the new DCEU, following the introduction of the new Batmobile and Bat-wing in "Batman v Superman."

According to a report from Comic Book Movie, these rumors may come true given the fact that Geoff Johns, who penned the "Throne of Atlantis" comic books where Atlantis waged a war against the Justice League and the rest of the world, now serves as a creative director and advisor for the DCEU.

Fans also speculate that allowing the Justice League to first face Atlantis and Aquaman will allow the filmmakers to further build up Darkseid as as formidable villain, properly introduce the Justice League superheroes and give some time to focus on the resurrection of Superman storyline.

"Justice League: Part One" opens in theaters on Nov. 17, 2017.

The information is revealed in the video below, starting at the 27:30 mark: