Loki and Thor, these brothers from different fathers and mothers, undoubtedly shared an extremely complicated relationship.
At first, Loki was merely jealous that his brother could win more applause, cheers, and their father's affection through bravery. He even looked down on Thor's reckless, impulsive nature and often pulled pranks to prove that he was smarter.
But as he grew older, he realized that no matter how hard he tried, the throne of Asgard belonged to Thor and would never fall into his hands.
When Odin publicly announced that Thor was the heir to Asgard, that intense jealousy and resentment finally reached its peak.
Soon after, Loki learned that he was not Odin's biological son at all, but an abandoned infant left behind by Laufey, king of the Frost Giants.
Those words Odin had spoken when he was young—"born to be king"—had apparently meant that he would one day return to the frozen Jotunheim and inherit the throne of the Frost Giants.
How could a naturally rebellious Loki possibly accept such an arrangement?
You must know, he had lived as the Prince of Asgard for countless years. He had long since deeply identified as an Asgardian, looked down on the Frost Giants, and looked down even more on the throne of Jotunheim.
There was only one thing he wanted: the throne of Asgard, the one prepared specifically for Thor.
To prove that he was superior to his brother!
That was the ultimate purpose and motivation behind all of Loki's actions, as well as the final curse that plagued his entire life.
Of course, he knew none of this yet. Pleased with himself, he believed he had successfully deceived his brother, swaggered out of the room, and even tried to pull out Mjolnir. In the end, he directly summoned the Rainbow Bridge