After years of fan campaigning, 2021 finally saw the release of Zack Snyder's Justice League. The movie was far closer to the director's original vision for the DC Extended Universe and served as a true endpoint to the loose "trilogy" that he started with Man of Steel. One element in the movie even included a much longer look at the now-iconic "Knightmare Sequence," showcasing other heroes in this ravaged future full of injustice. However, there was one hero who was notably missing.
Martian Manhunter formally debuted in the so-called "Snyder Cut," but he's nowhere to be found in the Knightmare Sequence. And that is despite the glimpse at a horrific future showing what became of two other powerful DCEU metahumans. But it may be that the last martian's fate was hiding in plain sight the whole time.
What Became of the Justice League in the Knightmare Sequence?
In Zack Snyder's Justice League, General Swanwick from 2013's Man of Steel reveals himself as the Martian Manhunter when he shapeshifts into Superman's mother, Martha Kent, and speaks with Lois Lane. He later reveals himself to Bruce Wayne, stating that recent events have made him want to act more openly in defense of the Earth. But that follows a dream that Bruce has foreshadowing the Knightmare Sequence, making Martian Manhunter's absence from the scene make sense.
However, the Knightmare is a potential future for the DCEU, not just a dream. Thus, the absence of the Martian Manhunter in this future is incredibly suspect. After all, Aquaman and Wonder Woman are dead by this point in the timeline, giving few options when it comes to directly facing an evil Superman after the death of Lois Lane, and Martian Manhunter should logically be a match for Kal-El.
Is Martian Manhunter Dead During the Knigthmare Sequence?
The most obvious explanation for Martian Manhunter's absence is that he, too, is dead in the future. After all, as a martian, he's susceptible to fire, making an angry Kryptonian with heat vision his worst nightmare. And that is exactly how Martian Manhunter met his end in the continuity of the Injustice: Gods Among Us games and comics, with Superman burning him alive when the hero tried to control Wonder Woman.
Another option is that he's in disguise somewhere, perhaps even as a parademon, waiting for the right moment to strike and attempt to take down Superman and Darkseid. And that would make sense, given how well he can "slip into character" without being detected. After all, even with his great senses, Superman couldn't figure out that Swanwick was also an alien. Perhaps the darkest route, however, would be that Martian Manhunter saw the Earth as a lost cause and let Superman and Darkseid rule it without a fight. Likely feeling that he revealed himself and acted too late, Martian Manhunter would've resigned Earth to its fate and went home.
However, in the backdrop of all of these theories is that Martian Manhunter wasn't supposed to be in Zack Snyder's Justice League -- at least not at the end. That was a role meant for a member of the Green Lantern Corps, but Warner Bros. kept Snyder from using them. Thus, it's possible that Snyder didn't even think ahead as to what Martian Manhunter's role in the Knightmare Sequence would've been, but given the current state of the DCEU, the answer may never come.