Heirloom Sword is one of the starter weapons which the thegn of Skjern gains shortly after the character has been created by the player. If one point is spent on the weapon skill sword, this weapon can be retreived from the weapon rack.
Your father inherited this sword from his father, who probably inherited it from his. It's a reliable weapon, but it lacks modern innovations. Your father neved used it on his expeditions.
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