The Ghoul ("destroyer") is the most malicious species, along with the Ifrits and marids who make up the wicked army of Iblis. There are male and female ghouls, the males are often sighted with matted shaggy hair that hangs over their eyes. The females are known as Si'lats, they are hideous in every way. The Ghoul is known to frequent the Valley of the Angel of Death, which is in the salt desert on the road from Teheran to Qum.
The male ghouls have the ability to shapeshift endlessly, but in any form will always have hooves as feet. The most common transformation that they take on is that of an ox, camel, or horse, but they also appear in human form. They lure humans into their camp by lighting fires at night and call out "Good evening!" as if they were humans to travelers to decieve them. One of the Ghoul's specialty is to sing like a siren, the voice is so sweet that the traveler would be lured into the camp, once the ghoul has the traveler alone, the Ghoul will show its claws, rip apart its prey and devour it whole. The female Ghouls operate much the same way.
Ways to disarm these monsters is to show generosity to them, if you be nice to them, they will be nice to you. But it isn't any type of generosity, it is rather specific. For the males you must cut his hair and groom him so that he can see well (no hair in eyes) and the ghoul will go out of his way to help the kind person. For the females you must the traveler must nurse at her breast and she will treat the person as if they were her own.
Another way to rid yourself of these Ghouls is, if you are not able to complete the above that is. One must loosen the belt of one's pants to repel them. Or a Ghoul can be killed with one blow, but a second blow will bring them back to life.