


Unfortunately, he didn't know the rules of immortality at the time, so he didn't behead Kanwulf and the guy survived. Duncan came back and took up his father's sword to go after the guy. After Duncan was cast out of his clan, it was attacked by a Viking named Kanwulf, and his father was killed. When Jon is resurrected, Davos returns Longclaw to him.

After Rhaegar Targaryen was killed by Robert Baratheon, his brother Viserys wielded his sword and was eager to get revenge.
