Swain's Vengeance by Arthur D. Howard Smith is about Viking Swain, Olaf's son, who goes on a journey to avenge his brother and his father. Excerpt: "You're holding treasures. It's tempting to call them lost, but it's more accurate to describe them as inaccessible because unless you had laid hands on an old hardback from the 1930s - which reprinted only a handful of Swain tales - or a long run of Adventure magazine from the teens and '20s of the last century, you couldn't read these..."