Draug

In Scandinavian mythology, a revived dead man who returned to the world of the living by his own will after a violent death or at the call of a strong sorcerer. 

The appearance depends on the type of death: water constantly flows from the drowned man, and bleeding wounds gape on the body of the fallen fighter. The skin color can vary from dead white to cadaverous blue. His body can swell to a huge size, which makes him much heavier and more sedentary.

Sometimes they remain undisturbed for many years. Sometimes the soul is preserved.

Draugs are often referred to as guardians of the treasures of burial mounds. At the same time, there are legends about draugs leaving their tombs at night to jump and jump on the roofs of houses, inspiring terror in people.

Draugs are credited with supernatural power and magical abilities: to predict the future, weather. Anyone who knows a special spell can subdue them.

It is also mentioned in the sagas that they are able to transform into various animals, but at the same time they still have human eyes and a mind that they had in "human" form. Sometimes they can pass through the ground.

Draugs can attack animals and travelers staying overnight in a stable, but they can also attack a dwelling. In connection with this belief, a custom arose in Iceland to knock three times at night (it was believed that the ghost was limited to one).