Ghoul is a demon-like being or monstrous humanoid originating in pre-Islamic Arabian religion, associated with graveyards and consuming human flesh. Ghouls are a race of monsters that feed mainly on the flesh of the dead and assume the form of their victims. In modern fiction, the term has often been used for a certain kind of undead monster.
Ghouls are scavenger creatures that live in graveyards and traditionally feed on the flesh and blood of the dead. At times ghouls will change their diet and will feed on living humans instead of the dead. Ghouls can also take the form of any person they have eaten, whether the person is still alive or already dead.
The only thing that can kill a ghoul is decapitation or complete destruction of the head. Bashing their brains in works as well.
Shapeshifting - Ghouls have the power to transform into any human, though they can only transform into humans they've fed off of, regardless of whether they are still living or dead. Like shapeshifters, ghouls also obtain the memories of the person they are mimicking.
Super Speed - Ghouls are said to move faster than humans, at least enough to escape unseen after a surprise attack.
Super Strength - Ghouls are stronger than humans. They can overpower a human, but they can also be fought off.
Super Agility - Ghouls are more agile than humans.
Enhanced Durability - Ghouls are more durable than humans, as one was able to take a shotgun blast to the torso and was only stunned. However, they are far from invulnerable.
Super Senses - Ghouls have a degree of enhanced senses, such as taste.
Decapitation - Complete removal or destruction of the head is lethal to a ghoul.
Extreme Brain Damage - Enough damage to the head, even without decapitation, can kill a ghoul.