Arctus will try to convince the Hero to light the fire for Dementia during The Cold Flame of Agnon. Additionally, he will explain how to perform the Ritual of Dementia. He is so devoted to Arden Sul that he never eats or sleeps; he wanders endlessly around the Sacellum Arden-Sul.
After completing both the "Addiction" and "The Lady of Paranoia" quests, the Hero must speak to Sheogorath. He will reveal that the real reason they are in the Shivering Isles is to stop the Greymarch by becoming the new Sheogorath. If they fail he notes, he will "swallow their soul and vomit it into the everfilling Chamberpot of the Ageless."
After fighting a sectarian battle in Cylarne and then relighting the Great Torch in the Sacellum Arden-Sul, Sheogorath appears in the pews, clapping delightedly. He says that the Greymarch is rapidly approaching.
"Ahh! You burn with the purging Fire of Agnon, the flame of Truth, the flickering beacon of hope in the gloom of depond! Come, light the Great Torch for Dementia. Illuminate the conspiracies! Deepen the shadows! The people of Crucible await their Hero!"
- I'm thinking about Mania, actually... "Oh no. You don't want to do that. Don't believe their lies. They are no true friends. Don't you see it? How they whisper behind your back? No, light the Great Torch for Dementia and you'll see how we treat our friends. Dementia takes care of its own. Few know that the Hero who lights the Torch for Dementia is granted the Ring of Intrigue, a boon for those who would gain access to hidden knowledge. Surely you will do what is right, won't you?"
- I'll light the Great Torch for you. "You are truly Demented, as I always suspected. Release yourself to your secret fears and desires. Let them rule you, as they must in the end! Now, light the Great Torch as a beacon for those who fear and those who inspire fear."
- Let me think about it. "Yes, let your mind worry at the problem. Let fear and dismay over making the wrong choice sink their talons deep into your brain..."
If told to think about it and approached again:
"It would be a truly Demented act to light the Great Torch with a Flame purchased with the blood of the Golden Saints. Come, light the Great Torch for Dementia!"
After lighting the Torch for Dementia:
"The Great Torch flares with the light of Dementia! All of Crucible will be celebrating tonight! Here. Take this. The reward you have earned. Quickly now. It's best if no one knows you wear this."
Replacing a Duke "Interesting. Not many wish to hear about such things, but I would be glad to oblige. Becoming the Duke of Dementia requires passage through the Ritual of Accession, specific guidelines set forth by Arden-Sul himself."
- Ritual of Accession "Seldom is the subject ever bro-... wait a moment, did you want to hear the history of the Ritual?"
- Tell me what to do. "Very well. Spoken like a true son of the Demented. To become ruler of Dementia, the current leader's heart must be cut out and brought to the Altar of Arden-Sul in the Saacellum. Once this is done, I can pronounce the heart-bearer a Duke or Duchess. Then, all that is required is the blessing of our Lord, Sheogorath."
- Please, explain the Ritual's history. "As it happened so many years ago, my lord Arden-Sul suspected a traitor in his midst. Not wishing to find himself on the wrong end of a blade, he gathered his flock here in the Sacellum. By poisoning the sacramental wine, Arden-Sul was able to suppress any such conspiracy in one fell swoop."
- He killed them all? "Yes. He then removed their hearts from their bodies and used his ancient scrying technique known as visceromancy to read their lifeblood. When Arden-Sul couldn't divine the traitor's true nature in their hearts, he became distraught and took his own life in the same way. From that day on, the Ritual of Accession for the throne of Dementia was set."
If approached again:
Arden-Sul "Blasphemy! Never utter the name of the Dark Deceiver lightly! Though his body is beyond Oblivion, his soul encircles us... always watching, waiting to pounce with lethal aplomb. He is the bringer of pain and pleasure; the blade that cuts through our sins like a scythe through wheat. Only a true Demented can appreciate what it means to render his name." Ritual of Accession "Didn't we go over this already? Bring the Duke's heart to the Altar of Arden-Sul. It's quite simple."
If chosen to become Duchess or Duke of Mania:
Thadon "If I were you, I'd check with Thadon's Steward, Wide-Eye. You can usually find her roaming around New Sheoth, or spending a lot of time on the palace grounds."
After killing Thadon:
"You've made your choice and forsaken the name Arden-Sul. I have no wish to speak to you."
- "How can I be of service?"
- "Pleasure and pain be with you."
- "Light the Great Torch! Let the flames proclaim the glory of Dementia across the realm!" —If chosen to light the Torch for Dementia
- "I'm disappointed in your choice. You'll find Mania to be a fickle friend." —If chosen to light the Torch for Mania