Sleipnir "Þorgrímsþula": "Hrafn and Sleipnir, splendid horses [...]". In addition, Sleipnir occurs twice in kennings for "ship" (once appearing in chapter 25 in a work by the skald Refr, and "sea-Sleipnir" appearing in chapter 49 in "Húsdrápa", a work by the 10th century skald Úlfr Uggason). In "Hervarar saga ok Heiðreks", the poem "Heiðreks gátur" contains a riddle that mentions Sleipnir and Odin: In chapter 13 of "Völsunga saga", the hero Sigurðr is on his way to a wood and he meets a long-bearded old man he had never seen before. Sigurd tells the old man that he is going to
Sleipnir legs may be the remnants of horse-associated divine twins found in Indo-European cultures and ultimately stemming from Proto-Indo-European religion. The encyclopedia states that "[...] Sleipnir is born with an extra set of legs, thus representing an original pair of horses. Like Freyr and Njörðr, Sleipnir is responsible for carrying the dead to the otherworld." The encyclopedia cites parallels between the birth of Sleipnir and myths originally pointing to a Celtic goddess who gave birth to the Divine horse twins. These elements include a demand for a goddess by an unwanted suitor (the hrimthurs demanding the goddess Freyja) and the seduction