Factual error: When Ray leaves his wife Gina and his car is hit by the truck he should still be in England, but when he is being chased through the streets he is in South Africa, the cops in the car are not in English police uniforms or vehicle, police livery is incorrect, and all vehicles have South Africa plates, not English number plates.
Factual error: The old percussion double barrel shotgun is firing modern shotgun shells, which would never work or fit in that gun, and furthermore are also made of plastic, wrong for the era.
Factual error: Smaller pieces of the comet start raining down in a highway setting. While small fragments of a comet can come down, they'd all be traveling at anywhere between 20 miles per second as the comet is an extra-solar comet. Those small pieces wouldn't make such piddling explosions, they'd be creating concussion waves that would rupture your organs and send vehicles flying. The heat even from those small rocks would ignite all foliage within 50-100 yards. (01:31:00 - 01:34:00)
Factual error: The "hard suits" the divers wear have soft, relatively normal gloves and soft joints. More akin to a football uniform with armor over spandex. They are at the bottom of the Mariana Trench, at 36,0000 feet below sea level. The pressure is over 7,000 psi. Without a hard suit, they would instantly be crushed.
Factual error: The Corvette owned by Bentwood is not a Z06 as shown in the movie. It is a 2014 C7 Stingray and can be identified by the Stingray logo on the side of the car.
Factual error: When first sucking a bullet from the wall into his gun, he then opens the previously empty magazine to find the bullet. Given he didn't work the slide (forwards or in reverse), the round should not be in the magazine, but in the gun's chamber ready to fire. (00:14:00)
Factual error: SPOILERS! While the ending of Al being arrested for murder at his own wedding is dramatic and cathartic, it wouldn't have happened that way. There's no way that the cops would have known to search the wooded area near the cabin; they would have needed to find physical evidence linking the cabin to Al; they would have needed to establish that Al had no alibi for the time in question; etc. None of that would have happened that quickly or that quietly.
Factual error: The Blackledges' car has a license plate that starts with 34. Montana uses the first two numbers on their plates to identify the county that the driver lives in. 34 is the number for Sheridan County which is in northeastern Montana where there are no mountains in sight, but the Blackledge ranch is set near the foothills of a mountain range as you would see in western Montana.
Factual error: The USMC Embassy Guard is an enlisted Marine Sgt. He is wearing a Commissioned USMC Officer's cover (hat) that has gold braid and gold oak leaf motifs on the visor. (01:20:15)
Factual error: While on the fishing boat, the flag flown has 50 stars, while the movie is set in 1941. The US didn't have 50 states, and thus that flag, until 1959. (00:30:08)
Factual error: Not only Mulan's horse is able to outrun an avalanche (at the beginning even unseen by the large enemy army who does not even notice the event occurring), but it also gallops through it undisturbed while Honghui is being carried away depicted as being in serious danger. (01:09:30)
Suggested correction: This is consistent with what you see throughout the whole film: Mulan consistently breaks the laws of physics because her "Chi" is strong. (Translating it to the Star Wars lingo: Strong with her The Force is.) Five minutes before (video time, not in-film time) she reversed the flight direction of a spear. This is a fantasy film and is supposed to do all of this; we watch it knowing that magic, "Chi", and The Force are not real.
That's a composition fallacy.
Factual error: He has a 55 gallon drum heater in his cabin which was not invented at the time.
Factual error: Both Nik Khan (Golshifteh Farahani) and the Colonel (Shataf Figar) are shown lining up their targets perfectly with the cross hairs in their rifle scopes. This is a common error in films. In real life, adjustments are made for wind and gravity, and the target is almost never lined up exactly in the crosshairs. Not only that, everyone in the film using sniper rifles makes several perfect kill shots, all on the first attempt and all without a spotter. Useful for movies, but extremely unlikely in real life.
Factual error: Apex, played by Robert Maillet (a retired professional wrestler 6'11" and 350 pounds), forcefully slams Becky (played by 5' tall fifteen-year-old Lulu Wilson who probably weighs under 100 pounds) horizontally with her back hitting the ground from waist-high yet Becky is able to get up with no incapacitating injury that would be expected. Becky also manages to brutally kill him (as well as the three other neo-Nazis).
Factual error: Trevor was driving ECTO-1 at over 60 mph. Podcast was driving the remote car and it was pulling away from ECTO-1. There is no way that the remote car could be going faster than ECTO-1, unless it was souped up, which it didn't appear to be when looking at it.
Suggested correction: There are plenty of RC cars on the market right now that anyone could buy that are capable of going 60+ MPH (the fastest can hit about 100 MPH). And if you take them apart, they don't look "souped up" at all. They just look like regular RC cars inside. Components don't have to look fancy to function fancily. You also have to account for the fact that the movie is highly fantastical, so there's no telling what kind of technology the RC car uses... for all we know, it could be nuclear-powered like the proton packs.
Factual error: After sleeping in and being late for practice, Jack is driving to the gym. It is supposed to be morning yet the shadows made by the sun show the sun is setting over the ocean and therefore evening.
Factual error: In the flashback scene to 1985, a shelf with VHS tapes can be seen. Some of these movies date from after 1985 (Dante's Peak, 1997).
Factual error: The film consistently mistakes Absinthe ban with Thujone ban. The United States Food and Drug Administration (US FDA) lifted the ban on Absinthe in 2007, 13 years before the events of this film. Thujone is still banned, and Absinthe products must contain less than 10 mg/kg Thujone content.
Factual error: After Maya Peters is brought into the recompression chamber because of an injury, the timer is shown counting down by hundredths of a second and skips from 1 to 0 without showing 0.99-0.01. (01:24:30)
Factual error: TV reporters said "home invasions" and mentioned trying to find the people who were responsible for the "70 robberies." Lance (in prison), was talking to a woman who was going to write a book and told her he got "twelve years" for "fifteen counts of robbery and vandalism." The crime Lance and the rest of the group were committing fits the legal definition of "burglary" in Illinois (basically, entering an occupied structure with the intent to commit a felony or theft inside; the structure does not have to be occupied at the time of the act). Because there happened to be someone at home during their last (intended) "burglary", this offense would be classified as a "robbery."