Erath the Blinded

Chains of Flame
When you first approach him, he will tell you:
 * Erath: Hello? You are not a gnoll, yet I hear the sounds of weapons and armor. Are you a demon? A rebel? Perhaps you have come to end Erath's life? That would be a mercy!
 * You: We are raiding the Firebrands. If you hope to escape, now is your best chance.
 * Erath: I have no chance to escape, for I am cursed. An efreeti named Rashad rules the Firebrands—though they stupidly think themselves free—and this wicked efreeti has cursed me with blindness! I think it amuses him to imprison a blind wizard in his library. He even hired a tourpe of ogre mages to ensure that I try no tricks! A furious look crosses Erath's face. Gods, I have endured this torture for too long! When will these monsters end my life?
 * You: Is there no way to break the curse?
 * Erath: I have struggled against the curse for years, performing brief experiments while the ogres are away. I have found an incantation to transfer my curse to a willing victim. But who would suffer such a burden? Erath pauses. It is much to ask... but... if you accept this curse in my stead, I will help you any way I can.
 * You: I will suffer your curse so that you may escape, Erath. (You are affected by Blindness Curse)
 * Erath: The spell worked! My sight is slowly returning! But... what is that sound? The ogres have returned!
 * You: I cannot defeat the gnolls without my eyes. I am sorry. (Walk away)
 * Erath: Though I yearn for freedom, I understand your decision. I would not wish this endless darkness on anyone.

If you talk to him while the ogres are attacking, he will say:
 * Erath: ?????????????????

After you defeat all the ogres, he will thank you:
 * Erath: My blindness is cured! Now I can finally leave this evil place. But first... there is a secret chamber in this library. I discovered the switch ages ago, and I will open it before I leave. May what you find there help you destroy the filthy gnolls and their masters!
 * You: May you enjoy a long life in the sunlight, Erath.
 * Erath: emember to search the secret chamber! Farewell, and thank you for returning my sight and my life!