The Spitter is a type of Special Infected introduced in Left 4 Dead 2. This female subject has developed an elongated neck and extended jawline that has torn the corners of her mouth, turning it into a gaping maw. The skin around the subject's torso area has sagged considerably due to the erosion of the connective tissues caused by the Spitter's most horrific mutation: the overdevelopment of acids within the stomach.
The Spitter is so named due to its ability to spit large globules of acid at prey. When survivors draw near, it will spit a ball of acid that will inflict heavy damage on whoever it hits. Upon impact, the acid will pool on the ground and inflict increasing damage upon whoever stands in it. The Spitter is vulnerable after spitting as it takes about 20 seconds for her to build up enough acid to spit again.