Urbiphages are extremly rare and extremly powerful entities from beyond this world. Like vampires, they feed on life, albeit on a much larger scale: Urbiphages feed on cities.
Most Kindred have never heard of an Urbiphage. There are only a handful of scriptures that deal with them. The earliest are the Devotions of St. Hugues, a text of the Lancea Sanctum that compiles 666 tales on how the Sanctified Arm of Longinus defeted various monstrosities, among them an Urbiphage. Other sources include the Book of Zhan, the account of a mage that first observed the infestation and midway turned to worship the entity, and the Golden Legend of St. George, which identifies the Urbiphage with the dragon that St. George defeated. Most of the modern research is the result of the writings of Leonata van Treskow, a member of the Ordo Dracul. Van Treskow speculates that the Urbiphage is attracted to large numbers of Kindred. The exact numbers seem to vary from case to case. If an Urbiphage continues to nest, the city falls into decay and internal corruption. Investments don’t pay off, crime escalates, food is overpriced or ill-prepared or both, and the street lights don’t stay lit. In time, it will eventually "spasm", as it brings the city down. During such a spasm, all supernaturals within the city are assailed by violent headaches. Afterward, all that remains from the city is a ruin, if not physical, then on a spiritual level. Lancea Sanctum texts quote seven omens: Fire, Flood, Earthquakes, Storm, Plague, Conquest and Drought. Van Treskow theorizes that an urbiphage actually arrives at the moment of disaster and then exists backward in time until that point in history when the vampire population was too low to support it. Having reached that moment, the urbiphage dissipates.
There are few ways to drive an Urbiphage off once it has taken hold. One way is to cull the local Kindred. Since a disproportional number of vampires has caused its appearence, Princes reason, a diminished number might drive them off. Naturally, most Kindred within the domain are in general opposed to such a solution and the resulting infighting can harm the city even more than the feedings of the Urbiphage. Another way is to sacrifice a "True Prince", a Prince so in tune with his domain that he feels its pain. The "True Prince" has to be chained to the highest point in the city at dawn. As it is, most Princes are opposed to such ways or try to cheat by appointing a quick "successor" to be sacrificed. Such scapegoats, however, fail to sate the demand of the Urbiphage.
In the world of flesh, Urbiphages simply manifest as a an oily, gritty gray light that is reflected from the ceilings of the city's buildings. To any mystic senses that are developed enough, what can be glimpsed of them looks like two-thirds of a polypous, swollen bat corpse, partially melted and suspended across the city center. The urbiphage’s trailing “wing” extends up from the city at an unpleasantly skew angle to the street grid and sort of sublimes away in midair, twisting away to join the invisible bulk of the thing. Even then, the spectator knows that what he sees is merely the tip of a much larger creature. They can not be fought or reasoned with, as their perspective is as removed from a vampire as a vampire is removed from an ant. They can only be appeased.
- , p.138-142