Sandu was an unremarkable fortune teller working at a traveling carnival. He used his abilities to steal from the audience, but his powers were limited. Loki the trickster god was watching the show and sensed the evil inside him. He decided to use him in his plans against his step-brother Thor. Loki used his Asgardian magic to increase Sandu's mental powers a thousand times over. He now had the power to gain as much wealth as he wanted.
Sandu went on a crime spree: robbing banks, race tracks, trains, and museums. He teleported a palace and claimed it as his own. He then lifted the United Nations building, demanding the representatives declare him ruler or be hurled into space.
Thor battled him early in his career. To help, Odin sent Megingjord the belt of strength via the Valkyries.
Sandu transported himself and Mjolnir away. His attempts to lift the hammer caused a mental short circuit and lost his enhanced powers. He was then defeated and taken into custody.