Hellhound

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A Hellhound is a supernatural dog in folklore. A wide variety of ominous or hellish supernatural dogs occur in mythologies around the world, similar to the often seen dragon. Features that have been attributed to hellhounds include mangled black fur, glowing red eyes, super strength or speed, ghostly or phantom characteristics, and a foul odor. Certain European legends state that if someone stares into a hellhound's eyes twice or more, that person will surely die. In cultures that associate the afterlife with fire, hellhounds may have fire-based abilities and appearance. They are often assigned to guard the entrances to the world of the dead, such as graveyards and burial grounds, or undertake other duties related to the afterlife or the supernatural, such as hunting lost souls or guarding a supernatural treasure. In European legends, seeing a hellhound or hearing it howl may be an omen or even a cause of death.

Powers and Abilities

 * Invisibility - Hellhounds are invisible to humans, except under special circumstances. However, there are supernatural creatures, such as demons and angels, can see them. They can also be seen by the humans they are assigned to hunt and through an object scorched with Holy Fire.
 * Invulnerability - Hellhounds cannot be killed by conventional means or weapons. However, weapons like Ruby's Knife, or an Angel blade, can kill them.
 * Superhuman Senses - Hellhounds' sense are extremely heightened.
 * Superhuman Speed - Hellhounds are much faster than humans.
 * Superhuman Stamina - Once a hellhound has the scent of its prey, it will never stop hunting him or her, unless it is killed or called off by its master.
 * Superhuman Strength - Hellhounds are very strong, they are able to kill humans and demons.
 * Tracking - They can locate any human or demon they are sent after.
 * Hallucinations -  When close to their prey, hellhounds cause their victims to experience hallucinations, so as to frighten them out of hiding and leave them defenseless.

Harming

 * Salt - It serves as a barrier which they cannot pass. Salt also harms hellhounds.
 * Goofer Dust - It can be used to create a barrier, like salt.
 * Devil's Shoestring - This herb can serve as a barrier preventing Hellhounds from passing through a door it's placed over.

Killing

 * Demon-Killing Knife - This special knife could kill a hellhound.
 * The Colt - This type of gun was effective on hellhounds.
 * Angel Blade - Hellhounds could be killed by angel blades.
 * God - God was the one who wiped out the entire species of hellhounds so he and innesance can also fully destroy them as well with not effort at all.