Only you, and a whole lot of hungry hungry zombies. Fortunately, you get constant airdrops to deliver fresh weapons and med kits. Now, if you can only live long enough to earn some achievements and unlock some bigger guns. When things get really hairy, call in an airstrike!
As Always, Good Luck and Have Fun.
left/right to move; spacebar to fire; down to pick up weapons and health; up to call airstrike