Most Marvel fans think that Odin favors Thor over Loki because the former is his natural son, while Loki is the adopted son of the giant Laufey. However, there is another, much deeper reason for Odin's favoritism, and it hides in the one-eyed god's past and his relationship with his brother Cul, the God of Fear.

Loki has changed role and aspect many times, but he is still mostly remembered as Thor's antithesis, his resentful adoptive brother who grew up to hate the God of Thunder. One of the reasons for Loki's bitterness is that Odin always favored his "real" son, Thor, during their childhood. While Thor is strong, fair, and brave, Loki is usually sulking, cowardly, and relying on cunning and magic rather than might. This makes Thor much more similar to Odin, but this is not the actual reason why the former All-Father of Asgard favored one of his sons over the other.