The Avengers: Thor
Thor could be one of the most powerful heroes in the Marvel Universe and a demigod to boot. The Norse God of Thunder for that matter and son of Odin. Odin wanted to father a son whose power would derive from Earth as well as Asgard. After being born in Norway, Odin swept him away to be raised into a warrior on Asgard. Odin's wife Frigga acted as his mother from that point on. As the son of Odin and Gaea his strength, endurance and resistance to injury are greater than the vast majority of his superhuman race. He ages at a slower rate than most while also immune to conventional disease. As a Lord of Asgard, he possessed the Odinforce which allowed him to tap into many unimaginable cosmic and mystical energies. Being the God of Thunder and controlling the hammer Mjolnir gives him the ability to control weather among other things. All of his abilities make him quite the handful in battle and a more than welcome addition to the Avengers team.
Thor is one of several powerful ancients who lives in a magical realm named Asgard. Over time, these ancients have been decreed as Gods or just simply legends or fairy tales. The young Thor was raised by his Asgardian father Odin and his wife Frigga while also being brought up with his adopted brother Loki, the trickster. Loki over the years grew increasingly jealous of his more favored sibling. Thor began to grow in popularity and power even more so on his eighth birthday, when Odin created Mjolnir for him and enchanted it with powerful magic. Odin promised that the hammer would be given to Thor when he had proved himself to be a worthy warrior. Thor then trained himself to be worthy enough of a warrior in his father's eyes so that he could one day wield the powerful Mjolnir. After spending eight years training and performing heroic deeds, he was declared the most greatest warrior in Asgard and awarded Mjolnir. As time passed, Thor began to become more and more headstrong and overconfident. Odin decided that it was time for Thor to learn some humility. Odin had his son surrender Mjolnir to him and sent him down to Earth in the mortal guise of a crippled young medical student named Donald Blake. He was also stripped of his memory and identity. As Blake, he learned the value of perseverance in dealing with his injured leg and he came to care for the sick and dying, first as a medical student then later as a physician. He would then became a successful surgeon later on when he relocated to New York. After spending ten years in the guise of Blake, Odin had suggested taking a vacation to Norway (his birthplace). In Norway he came across the Kronans from Saturn which he fled from into a cave, which oddly enough was the very place his mother gave birth to him. Inside the cave he found a wooden cane that Odin left there. Blake was stuck inside the cave when a boulder covered the entrance and in a fit of rage he struck the boulder with the cane and magically transformed back into Thor, and the cane into Mjolnir. As Thor he escaped the cave and drove off the Kronans.
Upon regaining his power as Thor, he still had no memory of his past life as an Asgardian god, although as time passed more and more of his memories came back. Years later, Odin revealed to him the purpose of making him live some time as Donald Blake. Thor decided to maintain the identity on Earth and continue his medical practice. He became increasingly attached to Earth after learning of his maternal heritage was on this world. The other part was because he loved humanity and he felt that he needed to experience that which only mortals could know. Thor came to divide his time between Asgard and Earth. Thor even fall in love with one of his nurses, Jane Foster. While Odin disapproved of Thor's love for this mortal, he also refused Thor's many request to make her immortal. Odin even went as far as to allow his evil adopted brother Loki to set the Enchantress on Thor to drive a wedge in between his relationship. Eventually their relationship did end on their own terms and Thor then renewed his past relationship with the warrior Goddess Sif on Asgard. Loki, however, was a constant thorn in his brother's side. Loki played a large part in bringing many of the Earth's Mightest Heroes together when he manipulated the Hulk forcing them all to band together to stop him.
Thor became a founding member of the team known as the Avengers. He continued to serve with them from time to time but for the most part he remained solitary. However he did return for a longer period of time when things turned ugly for Asgard, so much so that it was destroyed by the Ragnarok threat. Mjolnir returned to Earth and as Donald Blake he reclaimed it effectively reawakening Odin in the process for Odinsleep. Meanwhile, a clone of Thor had been create codenamed "Project Lightning" to be used during the Civil War between heroes. Thor used Mjolnir to recreate Asgard's capitol in Oklahoma. Soon afterward, Tony Stark meet with Thor in New Orleans explaining that he cannot just recreate an otherworldly city on Earth. Thor then explained to Stark that he knew of his clone that he had used and that in doing so he felt violated that his so called friend would do such a thing to wage a war among friends, many of whom considered Thor as close as family. Seeking a compromise, Stark explained that Asgard could be considered a foreign embassy, with diplomatic immunity granted to its inhabitants which Thor accepted. During the Skrull invasion, Thor flew to New York to join the gathered forces of nearly a hundred other superheroes to repel the Skrull attack. During the hectic battle, Thor was forced to sacrifice a fellow Avenger, the Wasp. When the Skrulls turned her into a last resort biological weapon that would have destroyed the planet.