Oblivion:Eldamil

Eldamil is a High Elf adept in the Mythic Dawn cult, and was one of Mankar Camoran's chief lieutenants. He's found inside the Forbidden Grotto of Paradise, and will aid you in removing the Bands of the Chosen. He will also help you fight Mankar Camoran, if you so choose. He wears a Mythic Dawn robe, a matching hood and a pair of braided leather sandals.

Eldamil was one of the Chosen of the Mythic Dawn. He helped plan the Emperor's assassination. He was also the one that opened the Great Gate at Kvatch.  While hunting down survivors after the battle, he was slain by three townsfolk who were hiding in a cellar. Thus, he was sent to Paradise. He has the magicka bonus conferred by The Mage birthsign, a bound dagger lesser power, as well as a leveled barrier spell and ranged shock spell.

For weakness, remorse, and an obvious distaste for the supposed "Paradise", the Master banished him to the Forbidden Grotto to torture his former comrades who showed similar ingratitude for the gift of eternal life.
 
Related Quests

Quest-Related Events
Paradise
When first spoken to:
:''"You wear the Bands, but you're no prisoner. Who are you? What are you doing here?"

You have two options to reply with the first being:
:My business is my own. Stand aside.
:"Wait. I know who you must be. You're the one who killed Raven and Ruma. They told me about you, when I was still in their father's favor... And now you're here to kill their father. Of course. You came for the Amulet of Kings. Then ... Martin Septim still lives? There is still hope to stem Mehrunes Dagon's invasion?"

::Martin still lives.
::"Perhaps Akatosh heard my prayers. Even here. Even after everything I've done ... Listen, I can help you. You need my help if you are to leave the Forbidden Grotto."

::Why do you care?
::"I bear responsibility for much of the evil that was done in Mankar Camoran's name. I would undo it if I could. I never thought I would have a chance to redeem myself, waiting helplessly here in eternity. But now you are here. Perhaps you can kill Mankar Camoran. Save Tamriel from Dagon's final victory. I can help you. You need my help if you are ever to leave the Forbidden Grotto."

The other option is:
:I'm here to kill Mankar Camoran.
:"Can you really do it? Can you bring this eternal nightmare to an end? Can you defeat Mankar Camoran? And free all the souls of the poor fools who followed him? Listen, I can help you. You need my help if you are ever to leave the Forbidden Grotto."

Either option will lead to:
:Who are you?
:"I was one of Mankar Camoran's chief lieutenants. I helped plan the Emperor's assassination. I opened the Great Gate at Kvatch. We were The Chosen. We saw more clearly than ordinary mortals. We would destroy the world, and remake it. Mankar Camoran was our leader, our teacher, our Master. He had the secret knowledge. He dealt with Mehrunes Dagon as an equal."
:Why would you help me?
:"I was at the sack of Kvatch. They had no chance. We took them by surprise, and we carried the walls in the first assault. But they fought on anyway. Desperately. They seemed to think this decadent, mundane world of theirs was worth defending. I was slain after the battle was over. Three townsfolk hiding in a cellar attacked me when I entered their house, hunting down survivors. They tore me to pieces, although I have no doubt they were immediately killed by my companions. I've had plenty of time to ponder my deeds since I came here. Ponder, and regret. An eternity of regret. For my weakness, the Master sent me here, to torture my former comrades who showed similar ingratitude for his gift of eternal life."

You then have the option of accepting his help or refusing it:
:How can you help me?
:"No one wearing the Bands of the Chosen can leave this Grotto. The door will not open, and there is no other way out. I can remove them, but I will need time. The Dremora overseer will be here any minute to check up on me. You need to play along until he leaves. Just act like a prisoner, and do as I say. Once Orthe leaves, we can find a quiet spot to remove those Bands."
::Fine. I'll play along.
::"Good. Follow me, and don't worry. You can trust me."

:I don't want your help.
:"I understand. Why would you trust me? But you have no choice. I am the only one who can help you escape this place. No one wearing the Bands of the Chosen can leave the Grotto. You'll discover that for yourself soon enough."''