Revealing mistake: When Red hits one of the demon bikers with his vehicle after he shoots it with an arrow, as the vehicle flips from the impact that there is actually nothing there he hit. (01:16:20)
Revealing mistake: When Brother Swan goes to blow on the "horn" (which is actually an ocarina), he toots out a few different notes. However his fingers stay completely stationary on the instrument and not moving around on the holes to change the notes. So it would have been just one sound but it plays like 3. (00:29:25)