Sigyn
God of Mischief and Fire
Sigyn is the wife of Loki, the God of Mischief and Fire. She herself is the Goddess of Magick, and a traitor just like her husband. She helped to bring about Ragnarok. It was Sigyn who aided Loki and Surtur in creating the spell that was used to send fell flames of magick throughout the Nine Realms until all life was almost extinguished.
After the Spell of Favouring was enacted, stopping Ragnarok and bringing about the Great Rebirth, Sigyn was locked in a tower and hidden away by Lord Odin so that she would never again be able to harm anyone or threaten Asgard. For a thousand years, the goddess has been by herself, alone, and the people of Asgard have felt safe knowing they will never have to fear her machinations again.
That was until Amanda was claimed, and became the first Favoured to have her benefactor be the traitorous goddess. What this means the realm can only speculate and tremble in fear because if Sigyn were to ever break free of her prison, they all know that Ragnarok could come to claim them all once more.