AboutThe Witch is a member of the Infected and the only one to display an initially passive response to presence of Survivors. She is also the only non-playable Special Infected.
The Witch is highly sensitive to light and the close presence of uninfected humans. Shining a flashlight on a Witch or approaching too closely will "startle" her and trigger an attack. Hitting her with a bullet has the same result. She is totally unresponsive to Infected and the passage of nearby bullets.
When alert to the presence of an uninfected human or flashlight, she will look in the human's direction and make a low warning growl: this signals an incipient attack. If the human backs off, switches the light off or moves quickly out of her presence, she will fairly soon settle back into a passive state. But if the threat persists, she will launch an attack directed at the human who "startled" her at great speed, singling out the person who provoked the attack. She is able to incapacitate her victim instantly whereupon she frenziedly slashes that person with her clawed hands, only stopping if either she or the victim die.
If an attack is successful and she is still alive, she will run off sobbing out of sight. She will display the same behavior if her attack is frustrated (e.g. the victim is able to outrun her), again she will give up and run away.
Killing a Witch is not always required, since players can often sneak around her or wait until she wanders away from their intended path. However if she is immobile because it is dark and it is not possible to go around her, the only option is to work out a plan to kill her.