The end is nigh. The infected are lurking everywhere and chances of survival are slim. Left 4 Dead focuses on the story of 4 individuals and their harrowing battles against the hordes of the infected that roam the streets. What about other survivors? What would they look like and what kind of deformed monstrosities would they be up against?
Due to it's slow speed, the herder relies on a bile similar to that of the boomer. With this it summons it's own personal horde of infected to hide it's presence as it approaches.
When close the herder deals insanely high damage, often resulting in the death of the unfortunate target.