Sigurd is a creature that appears in the episode "Chapter 4: The Eternal Warriors", as well as this episode's adaptation "Hilda and the White Woff". His role is the same in both continuities. He does not appear in the graphic novels.
Sigurd is a tall, slender, humanoid creature with green skin. His body is largely covered in mud from the swamp in which he lives. According to "Hilda's Book of Beasts and Spirits", Sigurd, like all Swamp Men, is actually made up of mud and vegetation.
Sigurd is usually calm and polite. He does not take kind to people stealing his stuff however, and thus has been keeping the Knudsen clan and Torgund's clan trapped in an endless battle over his medaillion. Although it initially amused him to see the vikings fight each other every night, he eventually came to see the task of reviving them every night as a chore that needed to be done.
Sigurd is at least several centuries old. He once had a medallion that could render anyone who touched it fearless, but at the cost of their common sense. It was stolen from him by either the Knudsen clan or Torgund's clan. Although Sigurd didn't want the stolen medallion back, since he knew it would make him reckless, he nevertheless didn't want to leave the vikings unpunished for their actions either. Soon after the theft, the clan that had stolen the Medallion was killed by their rivals. Sigurd used a potion to revive them, and wipe their memories about the fight, so they would track down their rival and kill them in turn. For the next centuries, Sigurd kept doing this night after night, reviving the fallen party and effectively trapping the 2 clans in an endless battle without them knowing it.
Hilda, David and Frida encounter Sigurd when they are on a Sparrow Scouts camping trip, and visit the Screaming Stones. They witness how Sigurd revives the fallen Knudsen clan, which where slain the night before. After the revived Knudsen kill Torgund's clan, including David, Hilda and Frida seek out Sigurd to ask for his help to revive David. Sigurd admits his whole scheme to them, and Hilda makes him realize it has gone on long enough. Thus, Sigurd revives Torgund's clan one last time, and tells them what he has done. The vikings take it in strides however, and consider it a good joke. Since he has no more use for the potion, he gives it to Torgund.
- The novelization does not show how Sigurd confesses what he has done to the vikings.