“It is a prison cell of powerful magic. The magic of the children of dust - magic that is strange to me.”
— when asked: What is that circle?
“Yes, more than anything. But as you see, I cannot. There is the gate, which Nil the White can unlock with his key. And there is this circle, my true prison, which can be broken by words only the priestess herself knows.”
— when asked: Do you want to be freed?
“She saps the power from my limbs and uses it for her own. She is as the cypress, standing tall in a calm, yet bending in the slightest breeze.”
“They brought me here to know the future; wanting riches, wanting luck. When I could give them none of those things, they spat and called me Tuatha, and left.”
— when asked about the Oracles.
“Is that why you have come? You will need Nil's key to open this gate. The magic words of the priestess will release me from her circle.”
— when asked: How can I free you, again?
Upon your return with the key and the magic words:
“Ah, my powers return! Benevolent child of dust, accept this gift. Find me among hill and dale. If you are hurt, I will heal you.”
— once you've freed him.
“The spell is cut like the tree's deep root. What powers she took from me have ceased to flow.”
When you search for him, once outside Burren Cove:
“It is done now. My powers are my own and the balance of Galafor has been restored. I have shown White Nil the nature of his soul. It appears he could not accept it, and now he will forever be a prisoner of his own mind.”
“This one is like a tree whose bark holds strong, but is rotten in its heart. I did no more than show him the truth of his ways. Perhaps it is not evenly balanced. After all, he will die so soon - less than a century - and then the torments he suffers will fade away.”
“The moment you broke her spell, the power she stole returned to me. Yes she used it as I would have done: to heal and nurture and protect. Therefore I did not treat her with a heavy hand, as I did with Nil the White....”
As a reward for freeing him, Adar will give the Fateless One a random enchanted Gem.
The Priestess had been feeding on Adar's powers while he was trapped, once he is free she will lose her healing abilities. Instead, Adar will offer the sames services to the Fateless One just outside the village.
Adar says that he showed White Nil the nature of his soul, instead of cursing him like the Priestess claims, and that the knowledge of it broke Nil. He didn't do anything to the Priestess but take back his powers from her, since he says she used them as he would have.