Vinland Saga

Young Thorfinn, son of the retired warrior Thors, watches his father killed by the Viking mercenary leader Askeladd during an ambush at sea. Consumed by revenge, Thorfinn joins Askeladd's band and fights across the Danish invasion of England, earning the right to challenge Askeladd to duels through battlefield service. Each attempt is another failure that binds him closer to the man he wants dead.