You Kill the undead By deatroying blood samples. blood samples are iron blocks with slabs on each side and redstone on top. skulls mark the area that you stay in. destroy all the blood samples to win the level. do all the levels in order. 
 use last days silent city resource pack. http://www.planetminecraft.com/texture_pack/minerp-zombie-edition/




                                        ENNNNNNNNNNNJOooooooyyyyyyyy!!!!!!!!!!!!!!!