even writers make mistakes sometimes, frequently these mistakes interfere with other parts of the story and create continuity. I am a person who is prone to point these things out so i have a relatively long list of them. so what is the biggest one, for me its in alien vs predator when thousands of aliens are running up the pyramid, for that they would have needed thousands of humans because after the chest burster comes out of the human they die thus can not make another chest burster