The fullest surviving eyewitness style account of seidr comes from Eirik the Red's Saga, describing a volva named Thorbjorg visiting a Greenland farmstead during a famine to foretell when conditions would improve. She was seated on a high platform built specifically for the purpose, wore distinctive ritual clothing and carried a staff, and required a chorus of women to sing a summoning song called vardlokkur, a chant one woman present reluctantly agreed to perform after initially refusing on religious grounds, in order to draw the spirits whose answers the seeress needed. Once the song succeeded in calling the necessary spirits, Thorbjorg answered questions from the assembled household about the coming season and about individuals' personal futures.
Scholars treat this account cautiously since it was written down centuries after conversion by a Christian author working from oral tradition, but its wealth of specific procedural detail, the platform, the special seat, the chorus, the staff, is widely regarded as preserving genuine pre-Christian practice more concretely than almost any other single passage in the saga corpus. The saga notes the household's initial difficulty finding anyone still willing to sing the old summoning song at all, a detail read by scholars as reflecting genuine anxiety within a Christianizing community about performing what was already becoming regarded as suspect practice.