In one scene, Ash smashes one of the zombies' hands in a door with the stock of his rifle.
Blood then squirts on the door, but in the next scene the blood is gone.
In one scene, Ash shoots a zombie in the face and blood squirts out. David Throughout the movie, the zombie's heads keep changing from different actors, and back to the same ones again. Also watch the hair as it changes from brown, to curly and white then back to brown again. When Ash is hitting one of the zombies in the head, the head is obviously fake and erected on a pole or something to that effect. If you look at the hand of the zombie locked in the cellar, you can see that the blue rotted skin is just a glove, because there is a hole in it, and in the hole is regular human skin.