One day, Ghilan'nain came across a hunter she did not know. At his feet lay a hawk, shot through the heart by an arrow. Ghilan'nain was filled with rage, for the hawk is an animal much beloved of Andruil. Ghilan'nain called upon the goddess to curse him, so that he could never again hunt and kill a living creature. Ghilan'nain's curse took hold, and the hunter found that he was unable to hunt. Ashamed, the hunter swore he would find Ghilan'nain and repay her for what she had done to him. He blinded her first, and then bound her as one would bind a kill fresh from the hunt. But because he was cursed, the hunter could not kill her. Instead he left her for dead in the forest. And Ghilan'nain prayed to the gods for help. Andruil sent her hares to Ghilan'nain and they chewed through the ropes that bound her, but Ghilan'nain was still wounded and blind, and could not find her way home. So Andruil turned her into a beautiful white deer—the first halla. —From Codex entry: Ghilan'nain: Mother of the Halla
According to Dalish tales, Ghilan'nain was a huntress of the People and Andruil's chosen and/or beloved. There is a number of different stories involving her betrayal at the hands of an elven hunter. In the end Andruil transformed her into the first halla, and Ghilan'nain rose to a godly rank.
Ghilan'nain is invoked when the Dalish wish to travel quickly or when their hunters struggle to find the way home.
This section contains spoilers for: Dragon Age: Inquisition.
According to an inscription in the Temple of Mythal, Ghilan'nain herself created giants, monsters, and beasts that spanned across the sky, water, and earth. These creatures Ghilan'nain had killed in three days after Andruil approached her with an offer for apotheosis, sparing only those "monsters of air" that she presented to Andruil as a gift, some deep sea creatures and the halla. She thus became known as the youngest elven god.
The sinner who dared to fly in the shape of the divine took wings at the urging of Ghilan'nain.