Thor is a fictional superhero who appears in publications published by Marvel Comics. The character first appears in Journey into Mystery #83 (Aug. 1962) and was created by editor-plotter Stan Lee, scripter Larry Lieber, and penciller Jack Kirby.

Debuting in the Silver Age of comic books, the character is based on the Thor of Norse mythology. Thor has starred in several three ongoing series; several limited series and has been a perennial member of the superhero team the Avengers, appearing in each of the three titles.
Thor's father Odin decides his son needs to be taught humility and consequently places Thor (without memories of godhood) into the body and memories of an existing, partially disabled human medical student, Donald Blake. After becoming a doctor and thoroughly believing himself to be the young surgeon Blake, he later discovers Thor's disguised hammer and learns to change back and forth into the Thunder God. The real Blake's persona remains elsewhere until many years later, after Odin becomes satisfied of Thor's humility and lifts the spell, thereby removing the need for a mortal alter ego.
Protector of Midgard Thor battles Hercules on the cover of Thor #126 (March 1966), the first self-titled issue. Cover art by Jack Kirby and Vince Colletta.Being the son of the Elder Goddess Gaea, Thor has a natural affinity for Earth and feels obliged to protect the mortals that occupy it. Thor's time on Earth is marked by battles against supervillains, monsters, cosmic beings, and even other gods.
Thor's principal foe is his adopted brother Loki, who has hated Thor since childhood. Although a master of magic, Loki usually avoids direct confrontations for fear of angering Odin. On one noteworthy occasion, Loki's tactics are accidentally beneficial - although successful in using the Hulk to draw Thor into battle, it results in the formation of the superhero team the Avengers, of which Thor is a founding and longstanding member.
A later timeline has Loki causing Thor to be separated for too long a time from his hammer, causing Thor to be thrust from Earth into another dimension or limbo, referred to as the "void."
Thor's hammer Mjolnir is found on Earth and put under U.S. Army protection. Sometime later, the supervillain Doctor Doom is escaping from Hell as Mjolnir falls through that dimensional plane, and tries unsuccessfully to claim the hammer, which eventually comes into the possession of a man carrying a bag with the initials "D.B".
Donald Blake, upon touching the hammer Mjolnir, is transported to the void of non-existence in which Thor now resides. Blake explains that when Odin originally removed the Blake persona from Thor, Blake was consigned to the void that Thor now inhabits. When Thor entered that void, Blake was suddenly restored to being, in New York City. Blake convinces Thor to wield Mjolnir once more, return to Earth, and renew the dual identity with Blake. --
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