The Sorceress of Castle Grayskull is a woman charged with residing in Castle Grayskull, to guard over the secrets and wisdom contained there. Teela Na, the mother of Teela, is the current Sorceress, having succeeded Kuduk Ungol long ago. Imbued with magical abilities by the Pool of Power, the Sorceress is an exceptionally powerful force, but she may only use her gifts within the confines of the castle she keeps. Outside Grayskull's walls, her only magical ability is to become Zoar, a falcon, and to communicate telepathically with several of her most trusted confidants.
The Sorceress provided Prince Adam with the Sword of Power to become He-Man, and similarly bestowed the Sword of Protection to Princess Adora so she could be She-Ra. She remains a trusted advisor and mentor to both heroes, particularly He-Man.
The character of the Sorceress is based upon an earlier figure who served the same role in the first Masters of the Universe stories. To avoid confusion, this other woman, who is always depicted wearing a cobra headdress, is generally referred to as the Goddess.
He-Man and the Masters of the Universe