i kindov made a new 1 .. well its a mix of all of them .. on veruct .. on the left side have at least 2 ppl playing with u and get enough points to open the stairs .. then down urself outside the hole in the wall on the top of the stairs and kill urself .... then use the glitch at the double tap machine and never open the little door behind u going into the bathroom....all the zombies will just go to the hole in the wall and stay there and the people you play with just stand and cover the window out on the balcony.. they can move around as long as they dont go infront of you

it 100% works.