Vile was the Mad Lord of The Cesspools, and was responsible for the dark infection outbreak.
Vile resembled a large black serpent with legs, with three sets of jaws in its rounded mouth, filled with needle sharp teeth. It had no eyes, normally existing in it's own realm, a dark cave within a bog, yet appeared to be able to see without them.
Vile could only exist in darkness and shadow, and used these shadows to move from the Gallows into Haven City where it began infecting the populace with it's bite. Vile was not a fighter; instead relying on it's contagious bite to turn humans into mindless thralls, doing it's work for it.
Vile was slain in Haven City by Grimm, who used infernal fire to turn Vile's body to ash, and it's disease was cured by Nicole who, using an unhatched egg taken from the Cesspools itself by Tara, created and antidote.