As title says, runner zombies can't hit you most of the time, especially if they are in groups. In 1v1, they manage to hit you about 50% of the time, if you stand still. In groups, they almost never hit you. Shamblers work for me fine. I turned on debug in the video just to make sure godmode was not turned on. If you enter a car, they dont ever attack it, just follow. All sandbox settings are like Apocalypse, except for runners on and infection off. See video for demonstration: