Other mistake: When the Predator sees Billy on the log bridge, there is a cold blotch in the middle of Billy's chest. He's not wearing anything that would make such a hole in his heat signature - it should be the same color as the rest of his torso. It doesn't even match up with the cut he made across his chest; the cut starts much higher than the blotch and the blotch is irregularly shaped, not indicating the smooth line of a cut. (01:15:20)
Suggested correction: The cold area is the blood running from his wound. It is cooling down on contract with the air.
Other mistake: The time of the chopper arrival for rescue (after the village attack) is said to be 09:30 but the voice on the radio says 10:30.
Other mistake: During the assault on the guerrilla base we see Mac running through the brush towards the camera firing his gun without aiming. It then switches shot to behind him, and he is turning towards a pair of men to shoot them. Plus the way he was moving and firing his gun isn't consistent with a professional soldier and their gun discipline and why would he be shooting randomly before engaging? (00:25:30)
Other mistake: Right at the end, Arnold fires an arrow at the Predator which barely takes flight and fires very slowly. He is shown making the bow very tight so the arrow should come out very quickly.
