Surtur was native to the extra-dimensional plane of Muspelheim and was the mortal enemy of the Asgardian ruler Odin and his son Thor. Surtur and the ice demon Ymir were older, and therefore more powerful immortals than Odin and Thor, who were always hard pressed to defeat them. Surtur was imprisoned for a long time within the depths of the Earth, but was once freed by Loki and set aganst the Earth when Odin visited there to break the romance between Thor and Jane Foster. Thor used Odin's magic sword to send Srtur to outer space, where he was bound against a magnetic asteroid. He was next summoned to Earth together with Ymir when the Spell of Fire and Ice was cast by the Sons of Satannish.
Surtur's role in the Ragnarok Cycle began by forging/reforging Twilight — a huge magical blade — and then sending his legions of fire demons to Earth, to draw Asgard's armies away from their capital city. Surtur then crossed Bifrost, the Rainbow Bridge, and attempted to destroy the city once and for all. Odin, Thor and his adopted brother Loki, however, made a last stand and eventually defeated Surtur - at the cost of Odin, who fell with his foe into a dimensional rift. After the final Ragnarok, Beta Ray Bill briefly visited the ruins of Asgard, and saw Surtur's massive form falling from the sky. Surtur was still clutching Twilight, although the sword was broken during Bill's battle with the demon Asteroth.
Surtur apparently died once and for all during the finalRagnarok when Thor managed to break the cycle. He was trapped in an afterlife dimension fighting a continuous battle with Odin, who prevented Surtur from escaping and returning to Earth by sacrificing himself over and over.
Surtur was depicted as an immense and malevolent being whose possesses the power of a thousand blazing suns. Surtur is an enormous fire demon, standing over 1,000 ft. in height. He is more of a force of nature than a physical foe. He possesses superhuman strength, stamina, and durability far surpassing that of Thor. He is possibly a being composed of "living" flame so strong that he can affect the Earth's tempreture from Asgard and can manipulate cosmic energy to generate intense heat, flames or concussive force, holding might deemed near-omnipotent. He can also manipulate cosmic energy for various effects, including levitation, molecular manipulation of himself, inter-dimensional teleportation, and immortality. He is vulnerable to intense cold, and can be imprisoned by certain magical spells or by other beings wielding cosmic energy powers equaling his own; Surtur's powers are usually shown to rival those of the All-Father's. Surtur is a master warrior and swordsman, and has a prehensile tail. He possesses an immeasurable intellect, and has vast knowledge of ancient and arcane wisdom.
The Eternal Flame has an unknown connection to Surtur. When in its vicinity, Surtur claimed it increased his powers. It is unknown to what extent this power increase leads to.
Malekith struck an alliance with Loki on behalf of the fire demonSurtur. He took control of a number of Earth humans using special food of the faerie provided by Hela. Malekith then killedEric Willis, guardian of the Casket of Ancient Winters, after learning its location.
As Master of the Hounds, Malekith hunted down Roger Willis, Eric's son and new guardian of the Casket. Malekith battled Thor, and kidnapped Lorelei. Using Lorelei as bait, Malekith forced Thor to battle Algrim the Strong, one of his Dark Elf followers, then attempted to destroy both combatants by plunging them into a pool of magma. He then captured the Casket of Ancient Winters from Roger Willis.
Malekith was ultimately defeated by Thor, but not before he destroyed the Casket of Ancient Winters, releasing magical frigid force all over the Earth. Malekith was then brought as a captive by Thor to Asgard. Malekith later disguised Loki as himself to take his place in the dungeon, while he disguised himself as Balder, who was about to be crowned ruler of Asgard. Kurse, the being formerly known as Algrim, saw through Malekith's disguise when he reached Asgard City. Kurse then broke Malekith's neck, apparently slaying him. Years later, Malekith was revealed to be alive once again.
Disguising himself as Balder once again, he enlisted Hercules to attack Alflyse, the Dark Elf Queen of the Eastern Spires. His scheme humorously unravels, and he is easily defeated by Zeus.
Believed to be killed by Kurse, Malekith later attempted to gain control of Avalon.
Malekith possessed various superhuman attributes, some of which are common to his race.
Superhuman Strength: Malekith, like all Dark Elves, possesses superhuman strength. Ordinarily, Malekith possesses sufficient strength to lift about 10 tons without supplementing his strength with his other powers. However, while using his other powers, he is able to increase his strength to the point where he can lift up to 90 tons.
Superhuman Speed: Malekith can run and move at speeds that are beyond the physical limits of even the finest human athlete.
Superhuman Stamina: Malekith's musculature produces considerably less fatigue toxins during physical activity than the musculature of an ordinary human. He can physically exert himself at peak capacity for up to 24 hours before the build up of fatigue toxins in his blood begins to impair him.
Superhuman Durability: Malekith's body is tougher and much more resistant to physical injury than the body of a human. Malekith can withstand powerful impact forces, exposure to temperature and pressure extremes, falls from great heights, and powerful energy blasts without being injured.
Superhuman Agility: Malekith's agility, balance, and bodily coordination are enhanced to levels that are beyond the natural physical limits of the finest human athlete.
Superhuman Reflexes: Malekith's reflexes are similarly enhanced and are superior to those of the fineat human athlete.
Extended Longevity: Malekith, like all Dark Elves, possesses a greatly extended lifespan and ages at a much slower pace than humans. He is also immune to the effects of all known Earthly diseases and infections.
Regenerative Healing Factor: In spite his his body's increased durability, it is possible to injure him. However, Malekith's metabolism enables him to repair damaged bodily tissues much faster and more extensively than a human is capable of. The limits of Malekith's natural healing abilities aren't known, but it is believed that he isn't able to regenerate missing limbs or organs without magical assistance.
Magical Energy Manipulation: Malekith can manipulate great amounts of mystical energy for a numer of purposes. Malekith has been known to often use his mysical powers to alter his shape and appearance. He can even use this ability to transform himself into a mist-like substance, allowing him to fly through the air over great distances. He is also capable of using this same energy to teleport himself across great distances, including between dimensional barriers. Malekith can also generate powerful blasts of concussive energy for destructive purposes. It is also believed that Malekith can use this mystical energy to increase most, if not all, of his superhuman physical attributes temporarily. He has used it to increase his physical strength and, since he was believed to have been killed by Kurse after having his neck broken, it is believed that he used his knowledge of sorcery beforehand to increase the limits of his natural healing abilities and for the purpose of appearing to be dead