As part of the Virtue Challenge, young Asgardians trekked into the Terasureyard every year in order to prove their virtue. In 1521, Thor, Loki, and Sif entered into a challenged against the Warriors Three and Brunok, Siegrold, and Hilda.
When Thor, Loki, and Sif entered the Treasureyard, the fairies that live their sent visions of the participants' fears. Sif saw herself becoming alone, Loki saw him and the others dying due to his scheme, and Thor saw himself being declared a failure. However, Thor overcame his fear and retrieved a Bone, helping his friends escape their own fears. The other two teams faced similar experiences.