Continuity mistake: When Amy says that she lost her earring, she's wearing shades. The shot cuts to Stacy and then back to Amy, who is now wearing spectacles without having had enough time to change her glasses off screen. (00:03:40)
Character mistake: Jeff mentions Mathias could have septicemia which he says is "a bacterial infection usually in the bone" However as a medical student he should know that septicemia means blood infection and has nothing to do with the bone.
Revealing mistake: When Stacy exits the tent before cutting herself with the knife, the rock walls behind her "shake" like they are a set or projection. It's odd.
Factual error: When Mathias is getting his legs cut off, he's raising his head and shoulders off the ground, although his back is broken.
Suggested correction: Depending on where the break is, this is possible.
Factual error: Jeff, being a medical student doesn't really seem to know how to make sure infection doesn't occur. In the scenes where he is cutting out parts of plant from Stacy's body he pours alcohol on her body before cutting it. This is totally useless as he doesn't put alcohol on his hands, the knife or inside the open wound after he cuts it. Infection as almost certain to happen because of this. This is practically impossible to not know by a medical student.
Continuity mistake: In the scene where Stacy is lowered into the temple to check on Mathias, the first time we see the crank there are about five loops of rope left on the wheel. After a quick shot of Stacy, the camera goes back to the crank and there are now about twelve loops of rope on the wheel, even though she is being lowered not raised.