Revealing mistake: Sloth is shown with three "arms." It's most easily noticed after he wakes up. His right arm is bent at the elbow, pointing to the ceiling, his left arm is pressed tightly to his left side between his torso and the jacket used to conceal the upper part of the prosthesis, and his third "arm", the prosthesis, is bent at the elbow, hanging halfway off the bed, and pointing to the left of his body. It has several large, protruding "veins" in it and the stump where the hand should be is off-screen.
Revealing mistake: Near the end, as they approach LAX, the woman says there is nobody on the ground, that it's just the same as Bangor, but actually you can see a few cars moving on the ground.
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: 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 everyone jumps from the plane, all of the stunt doubles are easily seen - [Dr. Elliot's stunt double is ridiculously easy to spot!] (00:37:00)
Revealing mistake: The fight scene between Peter Kurten and Andy outside the gay bar is viewed from behind a metal gate. Peter smashes Andy's head into the gate twice. The bars of the metal gate bend towards the camera as if they are made of rubber.
Revealing mistake: After Lucifer kills Gabriel, we get close-ups of Lucifer where the outline of his contact lenses are visible.