Sæhrímnir ("sooty sea-beast" in Old Nordic) is a creature that is described as a "Cosmic Boar" that is hunted, killed, and eaten every night, only to be resurrected so that it can be hunted, killed, and eaten the next night. It provides food for the Aesir and Einherjar in the feasting hall of Valhalla. Andhrímnir, the cook of the gods, is always the one to prepare its meat. It is interesting to note that Odin never actually eats the meat. Instead, he survives on the mead (an alcoholic drink in Nordic culture) from Heiðrún, and gives his share to his two pet wolves.
It is never truly revealed what Sæhrímnir is, but some have called it a boar.