Bárðar Saga - The Mound of King Raknarr
Gestr, the son of Bárðr, journeys to the far north to challenge the undead King Raknarr. With the help of a priest and a magic candle, Gestr enters Raknarr's burial mound and beheads the king and his 500 undead crew. However, the magic candle fails, and Gestr is only saved by the divine light of King Olaf, who drains the undead of their strength.