Hrunting

Hrunting is a sword given by Unferth to the player to defeat Grendel's mother. When used in battle, however, it does not hurt her. The player discards Unferth's sword and finds another sword to kill her. Unferth is unaware of this.

Background
Not much is known about the sword, apart from the fact that it is "a rare and ancient sword", and that somehow Unferth got ahold of it.

Characteristics
Unferth tells the player that the sword is a hilted weapon, and that it had been used many times in battles, therefore making it ancient. It also has a sharper edge than most other swords.