Revealing mistake: In a scene where the canoes are shooting the rapids through a sheer cliff you can clearly see a stuntman climbing out of the water onto the rock.
Revealing mistake: When the ship is upside-down and they're trying to get Susan down from the table, you can see that the table really isn't attached to the ceiling. You can see the center pool split into legs that are supposed to be connected to the floor, but when Susan moves around and shakes the table, the legs shake and you can see space between them and the floor. Even if the other legs outside of the shot were connected, the table would be leaning under Susan's weight.
Revealing mistake: When Weasel says, "How's your back, baby?" to Phyllis, she spits in his face, but Weasel closes his eyes before she spits.
Revealing mistake: At the beginning of the film O-Yuki is fighting the men in the forest and kills them one by one. When she kills the last one there is a close-up shot of her dagger entering his rib area and blood sprays out. However, if you pay close attention you can see the blood sprays out of his sleeve (presumably there is a device in there), not his torso. (00:01:18)