Deliberate mistake: When Kalidor beheads a warrior and when Sonja beheads the wizard, both heads don't fall sideways as they should, but instead fly upwards, revealing they were tossed by someone offscreen - which looks more impressive, indeed.
Deliberate mistake: The legion of hellspawns during the film's climax are merely copied and pasted throughout the screen, as evidenced by the fact that many of them perform the exact same distinguishable body movements, such as pacing right and left from a crouched position.
Deliberate mistake: Instead of being a specific language, Edward has an English to Asian dictionary. I've heard this was done to prevent a particular time period from being established. (01:12:55)
Deliberate mistake: The surviving passengers are all awoken from a deep sleep after Dinah realises the other passengers have gone. Yet none of them appear drowsy or tired and none of their eyes appear strained, despite having just woken up so suddenly. (00:09:20)
Deliberate mistake: Just after arriving in the 21st century, Thibault and André enter an elevator and scare away its occupants. Attempting to chase them, the elevator doors close despite their attempts to keep it open. Elevators have a safety mechanism which opens the door when they encounter resistance. This was ignored deliberately in the film for comic effect.
Deliberate mistake: In the housing block that Dave's house is in, the house numbers do not match - because In one shot of Claire walking past Dave's house, you can see that the house numbers are in the 1500's - one homes number is clearly 1516. However Dave's house number is 1958. However this is a deliberate mistake as the 1958 on Dave's house is a reference to when the Chipmunk fever was born. (00:23:50 - 00:32:35)
Deliberate mistake: Conan Stevens' character in this film is an unnamed orc who briefly attacks Gandalf and is defeated by Galadriel. However, in the first movie, the same character briefly appears in the flashback to Moria and is credited as "Bolg." This is due to the role of Bolg being recast and the two remaining filmed scenes of the original actor being repurposed. The filmmakers originally intended for first film Bolg to be a younger Bolg, but later retconned this, despite already crediting him as Bolg.
Deliberate mistake: During "Nobody Cares Like a Bear," Kim opens a gift box containing a balloon. Secret Bear then grabs it and floats away. But when Grumpy Bear tosses a star and pops the balloon, confetti flies out of it and, for the next second, keeps reappearing from nowhere. (00:14:05)
Deliberate mistake: Elizabeth will not be able to save Mateo from falling backwards into the fire pit by grabbing his hand or pulling him back after his whole body is suspended over the edge. (01:13:47)
Deliberate mistake: When a man bumps into pole, it sounds as if a truck had crashed (which makes it funnier), but in reality he just bumped his chest.
Deliberate mistake: After David jumps off the roof of the Firebrand building, it is discovered that he had been wearing a parachute, but this parachute was never visible on him at any point previously in the scene. Even when he was on the roof and after jumping, the parachute was nowhere to be seen. The parachute was too big to have gone unnoticed. It would have been visible whenever the shot was behind him and the straps would have been seen whenever the camera was in front of him. (01:17:30)
Deliberate mistake: When Larry and the two moving men are first bringing the mattress through the doorway and it gets "stuck," the camera placement makes it pretty obvious that the mattress isn't really stuck. There's far too much wiggle room on either end for it to be "stuck." (Obviously it needs to be stuck for the scene to work... but still a weird inconsistency).
Deliberate mistake: The ghost opens Nikolaj's bedroom door an inch or so, yet there is enough light emitting onto the hallway floor for the door to be open about halfway. After the door closes, the light on the floor continues to gradually fade towards the closed door. (00:17:05)
Deliberate mistake: When young Odette is sliding down the banister, and gets stuck spinning around the end of it, it would be impossible to spin like that without her legs hitting the rail that she just slid down.
Deliberate mistake: In the Spanish release, the name of the family store is written in Spanish, but inside the place it's in English everywhere. This is a very common mistake in foreign kids' films released in Spain.
Deliberate mistake: Throughout the whole short film, Geri's hair doesn't move or react to anything (such as the wind or his glasses). The glasses even seem to go through his hair without any movement in his hair. (00:01:00 - 00:03:35)
Deliberate mistake: In the end scene at the TV set, Scrooge tosses a coin out the window, and the camera follows the coin as it falls in slow motion. The people in the control room also watch this on their monitors. Problem is, this is a live broadcast and filming/watching something live in slow motion is impossible.
Deliberate mistake: When C-3PO, R2-D2 and the younglings are driving through the battle zone, Anakin Skywalker and General Grevious can be seen battling. Later, Darth Vader can be seen on Hoth. This would be impossible due to Anakin Skywalker being Darth Vader. (00:08:50 - 00:12:20)
Deliberate mistake: Gonzo and Rizzo are selling apples in the beginning, including the Red Delicious cultivar. That wasn't invented until the 1880s and the story is set sometime in the first half of the 1800s. Most likely intentional as they are the narrators.
Deliberate mistake: Luke had a box of T-shirts he designed and Faith reached into the box and removed the top T-shirt. Without looking at the size or even holding it up to her body to see if the T - shirt would fit, Faith asked, "How much?" Luke replied, "Ten" [dollars]. Faith reached into her pocket, pulled out a wad of bills and handed it to Luke without counting the money. Faith put the T-shirt on over her top and it was a "perfect fit." (00:03:55 - 00:04:37)