While the Loki of the Marvel comics and films does derive his cunning character from the Loki of Norse myth
Aurgelmir, also called Ymir, in Norse mythology, the first being, a giant who was created from the drops of water that formed when the ice of Niflheim met the heat of Muspelheim. Aurgelmir was the father of all the giants; a male and a female grew under his arm, and his legs produced a six-headed son.
Odin Borson was the former King of Asgard, son of Bor, husband of Frigga, father of Hela and Thor, the adoptive father of Loki, and the former protector of the Nine Realms. During the ancient times, he was worshiped as the god of wisdom by the inhabitants of Earth.
In modern literature (such as Marvel Comics) it has become popular to portray Loki as the adopted son of Odin. This however has no basis in Norse mythology, where Loki is portrayed as the blood brother of Odin.
Born to Frost Giant King Laufey of Jotunheim and abandoned due to his stunted stature, Loki was hidden away from the others of his kind. After slaying Laufey, Odin, ruler of Asgard, found Loki and took him under his wing to be raised alongside his son, Thor.
Yet as time went on and it came closer to telling Loki the truth, the Father in him couldn't do it. He didn't want Loki to feel like he was just a tool for peace. Which shows just how much Odin does love Loki. He was willing to set aside permanent peace between Asgard and Jotunheim JUST to protect his son.
Since the two were so fond of one another, it came to be that, at some point early on, they swore a blood oath. Though it is unclear how Odin and Loki met, their swearing of a blood oath may indicate that it was the result of the two fighting as allies in battle, against some common enemy.
Thor is the son of Odin, the All-Father and king of Asgard. He was worshiped by the humans known as Vikings and became part of Norse Mythology. Armed with his enchanted Uru hammer Mjolnir, which helps him to channel his godly energies, he became the mightiest warrior in the Ten Realms.
Hela appears in the live-action Marvel Cinematic Universe film Thor: Ragnarok, portrayed by Cate Blanchett. This version is the daughter of Odin instead of Loki, as well as the first Asgardian to wield Mjolnir (these features are partially taken from the character Angela, in her Marvel iteration).
Hela, Odin's first born, served as Asgard's Executioner and Goddess of Death, as her and her father made their way through the Nine Realms bringing death, destruction and conquest along for the ride. When Odin had a change of heart and wanted peace, he could not stop Hela's ambition and bloodlust; he imprisoned her.
It's revealed in God of War towards the very end that Kratos' son, who goes by Atreus, is actually the Norse god Loki. MCU fans will definitely be familiar with this character, but within Norse mythology, he is a Trickster god who is the driving force behind Ragnarok.
Both are destined to die at the hands of Kratos and his family in certain prophecies, Odin is destined to die at the jaw of Fenrir which is technically Kratos' grandson, while Zeus was destined to die at the hands of the Marked Warrior which is Kratos himself.
While the Loki of the Marvel comics and films does derive his cunning character from the Loki of Norse myth, the biggest difference is that in the Marvel universe, Loki is depicted as the adopted brother and son of Thor and Odin.
Odin and Loki is also mentioned as brothers in several text through Odins "dark side" Boelverk ("the evil doer"). That would, according to some, make Loki brother of the "giant part" of Odin´s soul (Odin had Bor, a Vanir, as father´and Betlsa, a giantess, as mother). These theories might seem confusing.
gods—Odin and his two brothers, Vili and Ve (some sources name the gods Odin, Hoenir, and Lodur). From each creator Askr and Embla received a gift: Odin gave them breath, or life, Vili gave them understanding, and Ve gave them their senses and outward appearance.
After spreading his mother's ashes with his father, he asked him why he was referred to as "Loki" on the wall drawings they found earlier which depicted their journey. Kratos then told him that his mother wanted to call him Loki, and speculated that this is the name she told the Jötnar.
Loki is Thor's adopted brother and the Asgardian god of mischief. In his younger years, he and Loki were very close and good friends, even if occasionally irritated by Loki's mischief. However, it is later revealed that Loki was often jealous of Thor even back then, and resented being left in his "shadow".
Loki did give birth to an animal in Norse mythology. He physically gave birth to Sleipnir, Odin's eight-legged horse, and was also its mother. Loki also fathered but did not give birth to, two animal children — Fenrir, the wolf, and Jormungandr, a giant snake also known as the Midgard serpent.
When Odin first found Loki, abandoned as a baby on Jotunheim, Loki changes from his Frost Giant blue to Asgardian pink. The theory is that baby Loki was able to see Odin's memories, including his imprisoned daughter Hela, and he manifested his appearance to look like her.
Early in the comics' history, Loki fell for a Goddess named Sigyn, who was already engaged to a member of Odin's Crimson Hawk guards, Theoric. To get Sigyn to marry him, Loki had Theoric killed and then impersonated him until they were wed.
The new "Thor" movie introduces Marvel's first major female villain Hela, played by Cate Blanchett. In "Thor: Ragnarok," Hela introduces herself as the Goddess of Death, and Thor and Loki's older sister.