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?
The delicate, highly strung flowers of the infected world these guys are tricky, when encountering with survivors they will invariably emit a wide band and horrifying wail which will alert every other infected in the area and bring them straight to the wailers location.The only way to stop the ensuing horde, which will continue as long as the wailer is 'transmitting' is, obviously, to cut the noise off at the source.
This however isn't easy Wailers are fast and will seek to out-manuevre the players while continuing to attract as much attention as possible.
If cornered wailers will jump at the nearest aggressor and cling to him making him pretty hard to hit while all the time biting at the target and doing more damage.