Jotuns appear in a wide variety of Norse mythological tales. They are the offspring of the primordial giant Ymir, and variously encompass giants, trolls, and other liminal beings. Their home is Jotunheim, a realm where the Aesir and Vanir gods often travel for adventure or other errands. Some jotuns were very wise, such as Vafthrudnir, who engaged in a contest of wits with Odin; others were brutish and belligerent, such as Hrungnir, who Thor slew with the hammer Mjollnir. Some gods also married jotun women, such as Skadi and Gerdr.