Revealing mistake: When the FBI agent is in the room of the court medic to get the cause of death, in several shots the sliced up corpse is breathing. (00:27:00 - 00:29:30)
Revealing mistake: When Brom (disguised as the horseman) throws the jack-o-lantern at Ichabod, there is a shot from Ichabod's perspective showing the jack-o-lantern flying toward him. It jiggles from side to side, revealing it was travelling on a wire.
Revealing mistake: At the fight scene in the cave, you can see the gun clip has no bullets in it.
Revealing mistake: You can see the plane intact even though it has exploded. It stays complete, there's just fire around it. (00:18:55)
Revealing mistake: During the party scene, when Jacob starts hallucinating, you can see the stick that one of the fake birds is attached to.
Revealing mistake: When Wally is firing the laser at random from the small spaceship, we see Fidget running down some stone stairs, and there are violent laser impacts directly behind him that could only have hit where they did if they had passed right though his body. (01:41:55)
Revealing mistake: When Sardo is aiming at Jarrell running you can see Kee Nang hiding behind a post, looking to the side waiting for her turn to get into the shot. (01:13:55)
Revealing mistake: In the gun battle following the bank robbery, Drucker fires his shotgun at Cherrito. A female pedestrian in the background (apparently unaware she's in the shot) can be seen acting casually, without any reaction to the gun battle taking place.
Revealing mistake: During the car chase when the car gets hit by the truck and goes into slow motion you can see the roll cage inside the car.
Revealing mistake: When Hamer goes to the gun store and obtains all of his weaponry, the gun counter guy and boy carry the weapons out to his vehicle. The weight of the weapons would be too much for one to carry all at the same time and the boy is supposedly carrying that large box of ammo, which would have contained over a thousand rounds, but he's carrying it like a box of feathers.
Revealing mistake: Jennifer swipes her card the wrong way at the studio and the door opens anyway. (00:57:15)
Revealing mistake: When Anita lies dead on the ground with her throat slit you can see her pulse in her neck. (00:53:05)
Revealing mistake: At the end when Norman is being stabbed at by Mary dressed up as Mother, Mary stabs Norman in the hand. You can plainly tell that this hand is a doll, as it is not a natural colour, it is stiff and is stationary, unlike Norman who is moving his hands. (01:35:10)
Revealing mistake: In the overhead view of the bus driving across the desert to Camp Greenlake the dust behind the bus is CG, and near the end of the scene the bus moves up in the frame and the end of the dust trail cuts off with a straight line.
Revealing mistake: When Bruce Willis is in the hospital, the doctor comes up to him and asks Bruce to look at him. The doctor proceeds to get a torch out and shine it into his eyes. Yet there is no light coming out of the torch. (00:10:25)
Revealing mistake: Towards the end of the movie, Hockney (Kevin Pollack) looks into a van and discovers it's full of cash. He is then shot from behind and blood splatters all over the money. When his chest explodes, you can see the plastic of the bag the blood was in. (01:18:10)
Revealing mistake: When Becky meets Simon in the cube, they hug, then Simon literally stabs Becky in the back. As she falls down to the floor, her black shirt reveals not only some of her chest, but part of a black microphone wire. (01:15:15)
Revealing mistake: When the Sergeant has the shotguns in the backpack on his back, and you see a close up of his face, you can see that the shotguns do not have triggers. On plastic prop rifles, the trigger is usually molded into the trigger guard in the pulled back position, and you can see this on these prop shotguns.
Revealing mistake: When Velma is running from the two one eyed skeletons she goes into what looks like a warehouse and the floor is all wet and in some places there are puddles. When the skeletons come they step into a puddle but the water doesn't even splash or ripple. (01:11:20)
Revealing mistake: After her brother's death, there is a scene in which Alice starts practicing with her brother's nun-chuks. They never show the real actress doing the tricks; instead, they cut to an angle from behind her and show a double who has darker, shorter hair than the real actress and is a bit bigger. (00:56:45)