WARNING: The following contains spoilers for Zack Snyder's Justice League, now streaming on HBO Max.
Zack Snyder's Justice League crafts a much more complete and superior film than the one released in 2017. It also allows the director to both establish and fully manifest narrative seeds for what he planned to do with other DC heroes. Beforehand, there were many unanswered questions stemming from Snyder's unfulfilled plans from previous DC Extended Universe movies.
Unfortunately, there are still a few of these left in the wake of the release of the so-called "Snyder Cut." Many of these were issues already present in the theatrical version, while the added material raises some new questions. Here are the various plot holes that Zack Snyder's Justice League leaves unfilled or opens anew.
Why Do the Atlanteans Make Air Bubbles?
One notable element in both versions of the film that was questioned by fans was the fact that the Atlanteans like Mera and Vulko had to create giant pockets of air to speak underwater. While this is a great visual, it certainly doesn't match any previous version of DC's Aquaman lore. Likewise, it makes sense that Mera is able to do this given her waterbending abilities, but this doesn't explain how Vulko is able to do the same.
Conversely, an Atlantean is later captured by Steppenwolf as he searches for one of the Mother Boxes. This Atlantean speaks fine on the land, and any ambivalence in his voice can be attributed to his being choked by the New God. This makes the previous fussiness over breathing ability even more questionable, explaining exactly why James Wan abandoned the concept in 2018's Aquaman.
How Will Clark Kent's Return Be Explained?
Though the color of his suit is different in each version, both films tentatively end with Clark Kent running into an alley and doing the classic Superman shirt reveal pose. His general look and demeanor suggest that he's resumed his usual routine in Metropolis and may even be working for the Daily Planet again.
It goes without saying that this is an extremely difficult situation to explain, especially given Clark's funeral. The coincidental timing of Superman and Clark's return raises further questions, none of which are addressed even in this cut of the film. Only Lois and Martha are shown reacting to Clark's return, leaving a gaping, Phantom Zone sized hole in the character's status.
Where Is the Modern Green Lantern?
The Green Lantern Yalan Gur was shown as being one of Earth's defenders in the ancient past, though he was killed in Darkseid's initial assault. Afterwards, his ring likely fled back to Oa or to a worthy successor. In modern times, however, there does not seem to be any Green Lantern in the vicinity. Steppenwolf even comments on how he's as sure of there being no Lanterns to protect the planet as he is that Superman is dead.
It is possible that Sector 2814 does not include Earth, which explains why it has no current emerald guardian. On the other hand, Zack Snyder confirmed in an interview that he did plan to involve a modern day Green Lantern in some way, so this being unanswered could possibly be attributed to time constraints.
How Did Darkseid Forget Earth?
Darkseid tries to invade Earth in the ancient past and soon discovers that the planet houses the Anti-Life Equation. Before he can attain it, however, he's beaten back by the conglomeration of Earth's forces. As he goes about conquering thousands of worlds, he never forgets the one planet that fought back.
Despite this, he does somehow forget which planet it was exactly. Thus, when Steppenwolf is informed by the Mother Box that Earth houses the Anti-Life Equation, it's a point of news to him and Darkseid. With all of Darkseid's technology and planning, it seems strange that he forgot the specific planet where the equation was located. This is especially true when another aspect of that planet remained so firmly in his memory.
What Was Steppenwolf's Great Betrayal?
The movie expounds somewhat on why Steppenwolf is no longer with the rest of the New Gods, but it doesn't go very far into the details. Desaad reveals that Steppenwolf had once betrayed and abandoned them and his conquest of Earth is part of his attempt to redeem himself and rejoin Darkseid's forces. This betrayal isn't shown or even explained, making Steppenwolf's desperation still ring somewhat hollow. Furthermore, this raises the question of why he even wants to go back to Darkseid, especially if he can somehow succeed in taking over the planet that Darkseid was beaten on.
How Did Batman Know Mera?
In the film's Knightmare sequence, Batman is shown in a dystopian future, teaming up with the Flash, Cyborg, Deathstroke and Mera. He obviously knew who the first two were, and he supposedly had some history with Slade Wilson. Conversely, he has never been shown meeting or hearing about Mera. This sequence is shown to be a bad dream, much like the one in Dawn of Justice, but this still doesn't explain how the dream includes someone who Batman is completely unaware of.
What Is the Knightmare Timeline?
Thus, the biggest question is what exactly the Knightmare sequence now is. It was obviously meant to be developed across Justice League sequels, resulting in a post-apocalyptic third film, but that didn't come to pass. In the context of the films, they appear to be just a series of bad dreams. Alternatively, the Joker mentions alternate timelines, planting the idea that this could also be an alternate future where things went awry.
Nevertheless, this is contradicted by the fact that these sequences are clearly depicted as Bruce's dreams. It at least made sense in Dawn of Justice, when Bruce so vehemently opposed and feared Superman. Following the Justice League's victory and Superman's heroic resurrection, however, its use as a mere nightmare is harder to explain. The alternate future route could still come up in the upcoming Flash movie, but as the DCEU currently stands, the Knightmare sequence still comes off more as a self-indulgent proof of concept than a narrative necessity.
Zack Snyder's Justice League stars Ben Affleck as Batman, Gal Gadot as Wonder Woman, Henry Cavill as Superman, Amy Adams as Lois Lane, Jason Momoa as Aquaman, Ezra Miller as The Flash, Ray Fisher as Cyborg, Jeremy Irons as Alfred Pennyworth, Diane Lane as Martha Kent, Ray Porter as Darkseid, Ciarán Hinds as Steppenwolf, Jesse Eisenberg as Lex Luthor and J.K. Simmons as Commissioner Gordon. The film is currently available on HBO Max.