Surtur is a fire giant native to the extradimensional plane of Muspelheim, land of the fire demons and one of the nine worlds in Norse mythology. He first appears in the title "Journey into Mystery", where it is claimed he sits at the end of the world waiting for the end of time where he can slay men and gods. The character's first encounter with the Asgardian ruler Odin is told in flashback and establishes their enmity when Surtur is imprisoned by Odin inside the Earth after forming an alliance with the Trolls and trying to destroy the world in anger for Odin defying him, although he gives Odin a winged horse, hoping to be released one day. Surtur reappears in "Journey Into Mystery" #104, having been freed by Odin's adopted son, Loki, who intends to usurp Odin and rule Asgard, having been given a portion of the Odinforce. Together with the Storm Giant Skagg, the character invades Earth, although the pair are met by Odin, his son the Thunder God Thor and fellow Asgardian Balder. Odin stops time and sends every human on Earth to another dimension. Surtur sends Thor into the ocean using a fireball. Skagg is saved from sinking into the ocean by Surtur hardening the ground, but is defeated by Odin, who is weakened by the feat. Surtur creates a blazing fireball and travels to the North Pole to melt the icecaps. Using Odin's sword, Thor stops Surtur and traps him on a meteorite of magnetic particles in another galaxy.