I know what i want in a game, but i havent found this game yet.?

i want a game with zombies. not like some "virus", but actual, old school, out of the grave zombies. it needs to have weapons, lots of them. i want a game where you can hire a party, like in fallout, and where you can meet different clans trying to survive the onslaught. you could ally the factions and team up on zombies and hostile factions. it should be open word. please don't say dead island, as that is a game that is already on my list of "things to by with my collage money". if my requirements are too demanding, how about a nice zombie strategy/ defense game. a version of nazi zombies with more than 4 ppl would be nice to. just tell me the name of the game im looking for.