Continuity mistake: When Nina dies, Bobby has her blood all over his face. When he picks his book up a few seconds later the blood is gone. (00:41:00)
Continuity mistake: When Billy the Puppet says "Hello Brad" Brad looks at the puppet, in the next shot, you can see he has his head below the blade, not looking at the puppet. (00:03:50)
Continuity mistake: At the end of Saw VI, Hoffman has got a massive chunk of cheek missing from the reverse bear trap. However in this film, which continues from Saw VI, he has not got a chunk missing. (00:09:00)
Continuity mistake: As Evan is tearing himself away from the car seat, you can see his back muscles are a fleshy-color and only have a little bit of blood on them. When he crashes at the end of the scene, his back muscles are suddenly dark-red and saturated with blood, despite looking totally different just seconds before. (00:20:25)
Answer: Dr. Gordon from the 1st movie, and Ryan and Brad from the trap in the beginning of this movie.
derrick g