After four years, the long-awaited and near-mythical director's cut of Justice League will release on HBO Max, boosted to four hours and entitled Zack Snyder's Justice League. It's a tremendously exciting time for fans of the DCEU and Zack Snyder, but it's tempered a little by the knowledge that the movie's story will end on a cliffhanger.

RELATED: Zack Snyder's Justice League: 10 Videogames To Play While You Wait For The Snyder Cut

Justice League was actually meant to be the first part in a planned trilogy of DCEU movies. Fans may never see Justice League 2 and 3, but storyboards detailing a potential plot for those movies have recently surfaced, along with some mind-blowing revelations.

The Riddler Was The Villain Of Ben Affleck's The Batman, Too

Left picture shows a Jim Lee design of The Riddler from Ben Affleck's canceled Batman movie, right picture is Paul Dano's Riddler from the upcoming The Batman

When the first trailer for The Batman dropped last year, fans were thrilled to see a new darker take on The Riddler, a villain who hasn't been seen in a movie since 1995's Batman Forever. Of course, before director Matt Reeves took the project in a new direction, Ben Affleck was set to star and direct in a version of The Batman that was part of the DCEU.

Not much is known about that movie, but the big surprise in the storyboards is that Riddler was also meant to be the villain in Affleck's movie too. He was going to die in Justice League 2 after solving the ultimate riddle: the Anti-Life Equation.

Dr. Poison Survived Wonder Woman And Lived A Century Later

Dr Poison from the Wonder Woman movie, complete with creepy porcelain half-mask

In both Wonder Woman movies so far, Diana vanquishes the main villain but the secondary villain disappears. In Wonder Woman 1984 Cheetah/Barbara Minerva slips away, and in Wonder Woman fans never discovered the fate of Dr. Poison/Isabel Maru (Elena Anaya).

Justice League 2 would've answered this question, as it reveals that Dr. Maru escaped to the forests of Brazil. She continued her obscene experiments on humans and used her Ares-given expertise to keep herself alive for well over a hundred years.

The Green Lantern Corps Arrives Too Late

Left image is art of the alien Green Lantern who appeared in Justice League, right is John Stewart Green Lantern from the Injustice 2 videogame

One of the most fan-pleasing moments in Justice League was the cameo of an alien Green Lantern during the ancient battle with Steppenwolf. While fans still don't know if the Green Lantern Corps will make any further appearance in Zack Snyder's Justice League, the original plan was for the Lanterns to make their full entry into the DCEU in Justice League 3.

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There would be at least two Earth-based Green Lanterns, possibly Hal Jordan and John Stewart, but at this point in the narrative, Darkseid's armies have decimated the Corps and turned Earth into the "Knightmare" seen in Batman V Superman. The arrival of the surviving Corps members would prove vital in the final fight against Darkseid.

The Legion Of Doom

Three images of supposed Legion of Doom members - Black Manta from Aquaman, Lex Luthor, and Deathstroke from the end of Justice League

At the very end of the credits of Justice League, there's a stinger that shows Lex Luthor's escape from Arkham Asylum and his meeting with Deathstroke (Joe Manganiello), where Lex comments that they should have "a League of our own." This was a reference to the Injustice League or Legion of Doom, the alliance of villains led by Lex Luthor.

This post-credits scene made it seem like Justice League 2 was going to ditch the Darkseid story entirely, but according to the storyboards this was always the plan, and at the end of the sequel Lex Luthor and Legion of Doom would have been revealed as working for Darkseid. The Legion would have consisted of Lex, Deathstroke, Riddler, Orm, Black Manta, and Dr. Poison.

Batman Gives His Life To Stop Darkseid

Left picture is the Knightmare future Batman with goggles and trenchcoat, right picture is Darkseid

The overall story of the planned Justice League trilogy was the invasion of Earth by Darkseid and the armies of Apokolips, and how the DC universe rallies against this ultimate evil. A lot revolves around Lois Lane. Aside from the information she has, Darkseid deliberately kills Lois to drive Superman to despair, but Batman saves her while catching most of Darkseid's Omega Beam blast himself.

According to the storyboards, in the final battle of Justice League 3, a dying Batman sacrifices himself to destroy Darkseid, much as he did in the iconic "Final Crisis" comics story.

Themyscira Gets Destroyed

Left picture is Wonder Woman in her golden armor looking concerned, right picture is an angry Dr Poison from the end of Wonder Woman

One of the biggest parts of the planned Justice League saga was the fact that Lex Luthor's Legion of Doom essentially wins at the end of the second movie, allowing Darkseid to control Earth. The saddest fate is that of Wonder Woman. While the other villains have less than perfect results, Dr. Poison's revenge is total.

Right after Diana finally returns to Themyscira, Dr. Maru's infiltration of the island allows her to unleash a chemical weapon. Diana, all the Amazons, and everything on Themyscira is destroyed, at least until Flash manages to go back in time and undo things.

The Lost Kingdom Of Atlantis

Left picture is King Aquaman from the end of his movie, right picture is the Batman V Superman Aquaman teaser poster showing a shirtless Aquaman with Unite The Seven written across it

The original teaser poster that revealed Aquaman (Jason Momoa) in the run-up to Batman V Superman had the words “Unite the Seven” on it, referring to the Seven Kingdoms of Atlantis. The first six kingdoms - Atlantis, Xebel, Fishermen, Brine, Trench, and Deserter - all appeared in Aquaman, but the seventh was only described as "the lost kingdom," as it was meant to appear in Justice League 2.

RELATED: Wonder Woman 1984: 10 Villains The Movie Sets Up For The Next Installment, Based On The Comics

According to the storyboards, the lost kingdom is called "The Unseen" and the movie was meant to begin with them staging a full attack on Atlantis, as they do not accept Arthur as their King.

The Flash Goes Back In Time

Left picture is a concerned The Flash, right picture is an armored Flash seen in the time travel sequence in Batman V Superman

One of the most surprising moments in Batman V Superman occurs immediately after Bruce Wayne's "Knightmare" vision in the center of the movie, where an older, armored Barry Allen seemingly speaks back through time and warns Bruce about Superman and the importance of Lois Lane. Justice League 3 was supposed to explain the context of this, as Barry is sent back through time, Terminator-like, while Earth has succumbed to the Knightmare.

Barry gets a second message to past Batman, who this time manages to stop Darkseid from killing Lois and enslaving Superman with the Anti-Life Equation. At this point, the future of the DC universe hinged on Barry Allen.

There Is Another Lost Amazon

Left picture is Diana Prince in a white outfit from Justice League seeing the news about the Shrine of the Amazons, right image is the Amazon Menalippe from Wonder Woman

One of the first images for Wonder Woman was a picture of Diana and three Amazons on Themyscira - Antiope, Hippolyta, and Menalippe. While the first two are important, Menalippe (Lisa Loven Kongsli) only makes a small appearance, but she was meant to be far more pivotal.

In Justice League, Diana wasn't just supposed to immediately know about Steppenwolf and Darkseid, but Menalippe was actually supposed to leave Themyscira and tell Diana in person. She would then be instrumental in helping Diana return to Themyscira in Justice League 2. Her role may yet get expanded in Zack Snyder's Justice League, but at the moment the only other Amazon to leave Paradise Island is Asteria, as revealed in Wonder Woman 1984.

Son Of Batman

Comics cover of Bruce Wayne's son Damian as a darker adult Batman with a large bat-symbol collar, with Gotham in flames behind him

Possibly the most shocking revelation in the storyboards is the fact that Batman is supposed to die at the end of Justice League 3, despite Zack Snyder having already established that Ben Affleck's playing an older Batman near the end of his career.

Possibly equally shocking is Bruce's planned relationship with Lois Lane after Clark dies, something audiences may see hints of in Zack Snyder's Justice League, and Lois even falls pregnant with Bruce's child. In the epilogue to Justice League 3, his son becomes the all-new Batman, similar to Batman Beyond or some of the future comic stories with Damian Wayne.

NEXT: 5 Reasons The Justice League Theatrical Cut Is A Worthy DC Movie (& 5 Why You Should Wait For The Snyder Cut)