Continuity mistake: Spot finds four other humanlike creatures and goes to them. Arlo is standing several feet in front of them. He begins to push some dirt by using his nose. A close-up then shows him using his nose to draw a circle around the five others but he is standing much too far away to be able to do this.
Plot hole: They have to invent Nitrotrinadium when they travel to the future because it was not invented yet, but was in the Russian drink in 2010, so should have already been available when they travel to the future.
Continuity mistake: In the early scene, when Maura is talking to the man in the corner, that she thinks is homeless, she stands up and has a green bag on her shoulder. When she asks for the sunscreen back, there is no sign of her bag. Then it's back on her shoulder.
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)
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)
Continuity mistake: When Shaggy and Scooby are approaching the Demon as he eats, it is shown that he is eating from a platter of hamburgers and french fries. Scooby and Shaggy bump into his table, knocking the food all on the floor. When Shaggy and Scooby quickly put all of the food back on the table, it now has french fries and hot dogs.
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 the woman is eating the bread roll on the train, the end of the roll switches from uneaten to having bites taken out of it and back again.
Continuity mistake: After Brad gets the electric shock, his shirt is completely clean but few shots later he has some burn marks on it.
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.
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.
Revealing mistake: In the Senior Citizen bus tour scene, just when the bus stops and almost hits the piece of construction equipment, Sofia Vergara is fixing her handcuffs. She adjusts them because one has visibly fallen off her wrist.
Continuity mistake: Lotte is in her room looking at the checklist for the parade. The size and angle of the quill pen change every time there's a cut. (00:14:40)
Other mistake: The town is Mt Barker. The red and blue ribbons on the sheep pen say Mt Baker.
Continuity mistake: At the beginning of the movie, the first thug is trying to convince Brennan to handle the gun. He repeatedly uses the trigger to show him that the gun is harmless; in the next shot the weapon mid-sentence is already turned around the other way, held out for Brennan. (00:01:15)
Other mistake: Whilst the main character is having a 'talk' with the general, the world clocks on the way show 3:50 on time 1, and 3:49 on time 2. (01:25:10)
Factual error: Summer and Carmen are at the saloon and catch on the local news the report of the kidnapping. The scene is set in Tuscany, Italy, but the news anchor is Spanish actress Paz Vega, speaking with an obvious accent and mispronouncing words. To make the whole situation even more absurd, she is supposed to portray a native Italian speaker, "Giulia Carni": the last name is Italian sounding but nonexistent in reality, and the headline used for the news report, "Nonna-napper", "kidnapper of grandmother" has such an awkward and unnatural sound and feel in Italian and for an Italian audience, that nobody ever would use it. (00:37:50)
Continuity mistake: The collision with the deer shattered the windshield in front of driver Ben, but when Ben skidded to a stop, there did not appear to be any damage to the driver's side windshield. When Ben and Carter were getting out of the car and when they were changing the front passenger side tire, the passenger-side windshield was shattered (and closer to the hood compared to midway between the hood and roof on the driver's side, which was no longer there). (00:10:20 - 00:11:04)