Loki

Loki is Thor's half-brother and the God of Mischief, imprisoned in Asgard because of his previous crimes. He escapes after manipulating Heimdall into shedding a tear, which breaks the enchantment holding him captive. Once free, Loki travels to Earth with revenge against Thor as his primary objective. Rather than confronting Thor directly, he uses deception and magic to create a series of increasingly elaborate traps.

Loki transforms civilians into strange negative versions of themselves, hypnotizes Thor, and creates a duplicate of the Thunder God in an attempt to obtain Mjolnir and exploit its power. His plan nearly succeeds, but Thor's transformation into Donald Blake breaks Loki's hypnotic control. Loki is subsequently defeated by Thor and returned to Asgard, where he must answer to Odin for his actions.

Loki remains imprisoned in Asgard as punishment for his attempts against Thor. He uses his magic to draw Thor's enchanted hammer away from Earth. Mjolnir crashes into the chains binding Loki and breaks them, allowing him to escape. Thor follows the hammer to Asgard and encounters Loki's enchanted forest, where Loki uses magical traps and animated trees against him.

Thor eventually recovers Mjolnir and defeats Loki. Loki is brought before Odin, who orders him to remain in Asgard and forbids him from following Thor back to Earth. Loki instead decides to continue opposing Thor indirectly and seeks out Sandu, a carnival mystic with unusual mental abilities. Loki dramatically increases Sandu's powers and directs him against Thor. In the end Thor proves too much for Loki's proxy and is defeated leaving Loki plot for another day.