Other mistake: Tony Hawk's crew recovers in a handful of seconds the three cameras that recorded Xander Cage's insane stunt. Considering it's 2 guys wearing sleeveless tank tops and one camera was strapped to the hood of the car (and the car fell hood-first, right on top of it) and the other was secured inside the burning car itself, you gotta wish someone filmed THAT operation, because sounds xtreme as hell. (00:09:10)
Continuity mistake: Senator Dick Hotchkiss leaves the car in the capable hands of the 'man from Tijuana'. He walks towards the club with his trophy blonde and shakes hands with two people. Meanwhile the valet puts the reverse and zooms away. The senator turns, but the two people he was chatting with are gone. (00:06:20)
Continuity mistake: After infiltrating the Rammstein concert using his sonic screwdriver, the secret agent is moshing his way through the rabid crowd. In the initial phase of the chase, shortly after Yorgi says "Zaraza" you can see that the band members are not wearing their mouth flamethrowers yet, or they already are, with no continuity. (00:02:10)
Factual error: The weapon Xander fires in the basement to kill the sniper with the might of his irony does not make sense (as noted before, it is non-existent and its prop is a modified camcorder). First of all, he is firing it with his back to the wall, and the deflected backblast alone would fry Vin Diesel's arse. Second; it fires a heat-seeking rocket that targets a single lit cigarette completely outside of Xander's range, to the point that the projectile does almost a U turn (way more than 90°); if it just goes for any smallest object wildly off the supposed target range (Vin Diesel is looking at a screen when he points it), then it could end up targeting the launcher itself, heated up by just having fired, or weapons or shells just fired by allies, making it useless in combat. Third; the screen Vin Diesel is looking at...is switched off. (01:38:40)
Factual error: There are no mountains high enough near Prague. The closest mountains that fit the description are the Alps between Germany and Italy.
Character mistake: When Xander tells Yelena "There must be something we can use", she goes through the manual and reads aloud "Harpoon, gun, parachutes built into seats, ejectable roof." Minutes later, Xander says that they must have missed something, and she says "Weapons, there are more weapons here in the back", and there's the harpoon gun she already read about earlier, she was even on that page of the manual. (01:43:50)
Other mistake: Coming out of the same door he went through at the beginning of his dungeon quest, Xander shoves back the guy he stunned; considering the sedative is supposed to last for 12 hours, what is he doing standing there? But if we assume that sedation in movies does not matter and you can just wake someone up with a slap on the cheek, fine; there's still a continuity mistake when we consider that Xander pushes him back quite far but when the two henchmen come out of the door they find him much closer. (01:19:20)
Character mistake: In the theater, Gibbons tells Xander that the scientists Anarchy99 have on their payroll are "specialized in biological weapons." But Silent Night, as it turns out, is not a virus or toxin, but it's chemical based, so their old Soviet creation they are specialized in is not a 'biological weapon' at all. (01:08:15)
Other mistake: The bad guy spots Xander snowboarding using telescope. The telescope's angle was too low to spot him as high up on the mountainside as he actually was at the time. You can see how far down the building is as he pauses to trigger the avalanche. Keep in mind that he was in fact higher up as he was spotted before triggering the avalanche.