Revealing mistake: When Krampus walks toward Max after he yells at him to give him his family back, wires are controlling Krampus' arm. (01:24:30)
Revealing mistake: When the twins are born neither baby has an umbilical cord attached to them. Also the baby girl has a bellybutton.
Factual error: Herman Melville interviews whaling survivor Thomas Nickerson in Feb. 1850. Nickerson tells him "I heard a man from Pennsylvania drilled a hole in the ground recently and found oil." Oil was discovered in Titusville PA in 1859.
Continuity mistake: After Brad gets the electric shock, his shirt is completely clean but few shots later he has some burn marks on it.
Continuity mistake: The getaway car changes from a Peugeot Partner (1996-2003) to a Citroen C3 Picasso (2013-2017). (01:35:30 - 01:36:05)
Continuity mistake: When Jesse Eisenberg seeks shelter at John Leguizamo's house, John Leguizamo pulls a gun on him. Jesse Eisenberg grabs the gun from John Leguizamo and in the close up of this action it's a completely different gun. (00:40:55)
Factual error: When he is in the restaurant and looking at the security feed, he does a who command when it should be "whois". Also the IP is incorrect - the 3rd octet is 265, despite the maximum possible value being 255.
Deliberate mistake: When Quinn is texting the boy next door, he responds too quickly for it to be real. She sends the "So you think I can stop traffic, huh?" text and gets a response within literally two seconds. She then sends the "Did I wake you up?" text and gets two responses within five seconds. Texts usually take several seconds (at least) to be delivered and opened, so even with great service and lightning-fast fingers, this is obviously far too quick.
Visible crew/equipment: When Bryson and Katz are getting onto the Greyhound bus, a guy in a fluorescent jacket can be seen holding traffic up in the distance whilst the scene is filmed.
Factual error: Near the end, Jackie Chan's vastly-outnumbered forces resort to throwing stones to somehow utterly destroy a phalanx of Roman legionnaires in close-quarter combat. This scene flies in the face of what we know about Roman military superiority in the time of Tiberius. The Roman Army was the best-trained, best-organized, best-equipped military force of the Ancient World, specializing in tireless close-quarter combat and impenetrable defense. To suggest that Jackie Chan's frantic and disorganized group of fighters (throwing stones by hand) might overcome Roman legionnaires is like suggesting that cave men might overcome the modern U.S. Marine Corps.
Continuity mistake: At the end, the TV newscaster reports that 150,000 reserve human forces have been activated. But the crawl strip at the bottom of the screen reads "150,000 RESERVED human forces," a different meaning altogether. (01:59:00)
Continuity mistake: When Bianca takes Wes to the "thinking rock", as they talk and her hands are in her lap, her hair moves from over her left ear to behind her left ear and back, twice.
Other mistake: When Marry Anne flies into the dark forest for the first time she drops the boutonniere. After seeing the primrose petal she flies off empty handed but has the boutonniere later when she meets Roland.
Continuity mistake: When Gordo leaves Simon and Robyn for a few minutes to handle a work thing, Simon starts mocking Gordo in his absence. Simon tells Robyn that Gordo wants to nail her and Robyn says "Stop it," but Simon continues his mocking of Gordo. At the end when Simon is listening to the recording that Gordo made of that conversation, Robyn's "Stop it" is absent.
Character mistake: The poster on the wall near the start reads "Our Egg Donor's [sic.] are helping to fulfill the dreams of women across America." There is an unnecessary apostrophe in the word "Donor's." (00:10:05)
Other mistake: Ma and Jack bake a cake, but there is no way of doing this as they have no oven - only a work top hob and a grill.
Continuity mistake: During the fight in the garage, the protagonist neutralizes (and maybe neuters) one of the baddies crotching him with the car door. In that sequence, his hands keep changing position on the door. (00:07:30)
Other mistake: When Otto Preminger calls Trumbo from his car to announce that Trumbo's real name would be credited for Exodus, Preminger tells him to look at the front page of the New York Times. The problem is that Trumbo has already picked up the paper from his counter and is reading before Preminger even tells him which newspaper features the article.
Continuity mistake: When Peter Pan is fighting the tribe's Pan on the trampoline and they're just about to finish Peter Pan off, the elder chief calls for the fight to stop. Peter's arms are above him in the overhead shot but are outstretched in the view from behind Peter.