Yugioh zombie deck?

what i want to know is why do most people who say they have a good zombie deck always include these cards (card trooper and neos spacian mole). i dont understand why these cards are always put in a zombie deck and i want to know why. cards i beleive are good in a zombie deck that are not zombies are (1cyber dragon, 1snipe hunter, 1sangan, 1jinzo and 1 giant rat).