The draugr is a corpse of Norse myth and saga that lies in its barrow guarding its own treasure, falling upon grave-robbers with overwhelming strength and at times changing shape or swelling in size. One of the archetypes of the tomb-guardian undead, it also shaped the later image of the "wight."
The body the sagas describe is not a living one. The skin is death-blue (hel-blár) or corpse-pale (ná-fǫlr), and the corpse swells until several men together cannot lift it. It is stronger than it was in life, takes the shape of a seal or a bull or of smoke, and enters the dreams of the living to sicken or madden them.
The best-known case is Glámr in Grettis saga. A shepherd who dies on Christmas Eve and will not stay dead, he kills livestock and men until Grettir beheads him — but not before Glámr lays a curse: that Grettir will forever see his eyes in the dark. The hero wins by strength and is left afraid of darkness for the rest of his life, which makes the tale a slaying and a failed slaying at once.
The remedies are set down as plainly as the hauntings. Behead the corpse and lay the head apart from the body; burn it and scatter the ashes at sea. As prevention, carry the dead out not through the door but through a hole broken in the wall, so the way back is forgotten, or pile a cairn over the mound to hold it down. Behind these procedures lies a view of death as a condition to be managed rather than an ending.
The line runs on into Tolkien's barrow-wights, the Nordic crypt undead of the Elder Scrolls games, and the tomb-guardian monsters of tabletop roleplaying. What usually survives the transfer is the fixation — the refusal to release what was its own — while the more awkward details, the dream-visits and the swelling weight, are quietly dropped.
Its fixation — unable even in death to release what was its own, and so keeping the grave — shares a register with the dread of a ledger that does not close even after the end.