Character mistake: Diana categorizes without a doubt Aquaman as "a mixed blood" Atlantean because Bruce tells her that he could breathe air. However Steppenwolf interrogated one of the guards from Atlantis on the ground, and he could breathe just fine.
Zack Snyder's Justice League (2021)
1 character mistake
Directed by: Zack Snyder
Starring: Ben Affleck, Amy Adams, Jared Leto, Henry Cavill, Gal Gadot, Ezra Miller, Ray Fisher
Other mistake: Barry comes back to his home, replaces the fuse in the fuse box, flips the handle (begs the question of why remove the fuse AND turn off the switch, but whatever), and within 2 seconds every screen in the place is lit up. Sure, a TV might come on that fast, but plenty of those screens are showing data, analysis, etc, running off computers, which would take longer than that to boot up and get everything running.
Wonder Woman: You said the age of heroes would never come again.
Bruce Wayne: It will. It has to.
Trivia: Director Zack Snyder has a cameo at the coffee shop while Lois is outside of it.
Question: When did Martian Manhunter get to Earth, why did he assume Martha Kent's identity, and where is she during Justice League?
Answer: Martian Manhunter is played by Harry Lennix, who also plays General Swanwick, a character who appears in Man of Steel and Batman v Superman (and we can see he transforms back into Swanwick he leaves), revealing that Swanwick was Martian Manhunter the whole time, so the indication is he got to Earth before Man of Steel. He assumed Martha's identity to speak with Lois, specifically to have a heart to heart with her as she is depressed due to Clark's death. Martha is present every other time we see her, when she leaves the Kent home at the beginning and when she reunites with Clark later on. This scene was the only time Martian Manhunter used her identity.
Casual Person