Regardless of whether Lyranth was freed in Ten-Maur-Wolk, she will be in the Tower of Lies. She will appear on and off throughout multiple areas along the way. After Arakh's helmet is returned, the following conversation occurs:
Captain Arakh: "You killed Ifriz, Eilram! What else could there possibly be left to talk about?" Captain Eilram: "Get a hold of yourself, Arakh! Ifriz isn't one of ours. He's the bastard that runs this place. You're being manipulated. Here's our roster. You won't find Ifriz on it." Arakh: "Let me see that! I'm sure I knew him. Didn't I?" Eilram: "We need to figure out a way to get our of this Tower of Lies." Arakh: "Who's that? Is that a Dremora?" Lyranth: "I grow weary of this situation. It's time to put an end to Ifriz's interference. You need to kill Ifriz. I need him dead. It seems we have a common goal to discuss."
Speaking to her will reveal that Ifriz is hiding behind illusions, and that she has removed them. She wants Ifriz dead so that she may retrieve something he has. After he is killed, Lyranth will appear and say: "Well done, little mortal. You killed Ifriz and I didn't have to lift a finger. Delightful! You and I will meet again, I think. I look forward to seeing what trouble you get into next." and disappear.
Vanus Galerion: "Be gone, foul creature! We don't have time for your games." Lyranth: "Mortals are always so amusing. I offer information, aid for your quest, and you shun me." Vanus: "You expect us to trust a creature of the planes? Ridiculous!" Lyranth: "A mer as arrogant as a kyn. How delightful! I do so love watching egotistical braggarts stumble. I may allow you to reconsider my offer. Of course, I may not. I haven't decided yet." Vanus: "You there. Find out where that creature is lurking. I want her watched."
Later on, Seris will be waiting for you at the sealed door to the Reaver Citadel Pyramid. She will ask you to kill Valkynaz Seris, explaining that he overthrew her Foolkillers Clan. After agreeing, Lyris opens the door, and says "The way is open. Destroy Seris. Painfully. He deserves whatever horrors you decide to inflict upon him."
Once Valkynaz Seris is defeated, she will appear where he fell, saying "My lost clan awaits in the darkness. Even though the blade that banished him was not in my hand, his end was my doing. You have been a most useful weapon, little mortal. Take the Labyrinth key, with my thanks."
"Ah, a new guest has joined our little party! And will you provide amusement and interesting diversion? I think you just might, at that!"
You're a Dremora, aren't you? "It speaks. I suppose I should be impressed that one of your kind even dares to approach me."
Daedra don't usually speak to mortals. "Pity. To think they'd miss out on this fascinating conversation."
Are you one of the prison wardens? "Oh, little mortal, you amuse me so! Surely you have more important things to do than waste time with me? Aren't there rocks that need to be chipped or bugs to be swatted? Perhaps you need to mutter to yourself and wander around in circles?"
Does this place make people do those sorts of things? "Most of the guests here suffer from one or more such afflictions. If you linger long enough, perhaps you will adopt one of these distinctive quirks. Or perhaps not. I will continue to watch with interest to see what develops."
"You seem determined to make yourself useful. What strange habits you mortals have."
You look familiar. "Really? Most mortals look alike to me. Plus, there's that smell. The odor of warm blood and quiet desperation. Mildly unpleasant, if you don't mind me saying so. Ah, wait a moment... I do remember you."
Why are you in this place? "The mortal continues to speak to me. What does it want, I wonder? Perhaps if I ignore it, it will just go away."
You were imprisoned last time, too. I helped you. "I assure you, contrary to the way it looks, imprisonment is not my usual situation. But before you get any ideas in that mortal little head of yours, I do not need your help this time."
I'm helping the Fighters Guild find a way out of here. "How fortunate of you. I shall enjoy observing how you go about accomplishing that particular miracle."
"Ah, mortal! You are a curious creature."
What are you doing up here? "You don't really expect me to answer that, do you little mortal? Needless to say, it amuses me to bide my time here and observe your plight. No need to concern yourself about my safety, though, for the lesser Daedra will not harm me."
Do you know where I can find the Fighters Guild captains? "Oh, yes! Watching them has been very entertaining. They struggle in a web they cannot see and it makes me laugh. You mortals! So easy to manipulate and so much fun to play with."
So you're the one behind all this? "No, little mortal, I am neither your jailor nor your tormentor. I am merely a disinterested observer who finds some tiny enjoyment in your predicament."
Why do you care what happens to me? "Even if I cared to explain myself to you, I doubt that you would understand. The politics of Oblivion are much too convoluted for your primitive mortal mind to comprehend."
Can you help me free the Fighters Guild? "I will not hinder you, dear mortal. Consider that to be enough help for now. Know this, however. The exit from this place is currently... unavailable. I suspect you will rectify that in the near future."
"We share a common problem, little mortal. It only makes sense that we work together to solve it."
Why would you offer help now when you didn't seem interested before this? "Do either of us have any other options? Ifriz created the barrier that blocks the way out of this prison. Eliminate Ifriz and the barrier collapses. But you must find Ifriz if you are going to kill him."
Can you direct me to Ifriz? "How sweet of you to ask! Ifriz hides behind illusions. I have removed them. He has something of mine. I want it back. Kill him, and both our problems are solved. But hurry. He will soon discover his defenses are down and hide himself again."
I'll deal with Ifriz. Will you help? "Ah, little mortal. I have provided more help than you deserve. The rest, as they say, is up to you."
"Ifriz is never far from his beloved barrier. Hurry and end this so that we can both get on with our existences."
"Ah, little mortal! While it might be entertaining to watch you bumble about the Citadel, I would much rather just see you get about your business. I'm sure that whatever you have planned will ultimately work in my favor."
Why don't you just tell me what you're talking about? "Right to the point? How distressful! Oh, very well. You seek a way into the Citadel, one that won't attract any undue notice. As it happens, I know just the thing. If you follow the east wall, you'll find a branch that leads inside."
Why are you helping us? "Never look a gift daedroth in the maw, little mortal. I offer information, nothing more. The warded building you seek is near the main gate. The kyn will try to stop you. If they don't succeed, we will speak again."
Does this have anything to do with what you were doing at the Tower of Lies? "Ifriz had information I needed. It ultimately led me here. I enjoyed what you did to Ifriz, little mortal. I'm looking forward to seeing what mayhem you stir up here."
I'll look for the breach. "The old Fighters Guild Hall. It's near the main gate. Go!"
"And so, the little mortal, once more into the breach! I believe the Ayleid King wants you to find a hidden key. Hurry! I think your friends have already made it into the sealed hall."
Why isn't this break in the wall guarded? "How amusing! The little mortal suspects a trap. You are wise to fear the duplicity of Dremora, but I assure you that you are safe enough. Illusions hide this area from the kyn. Just a little trick I recently picked up."
Why are you helping us? "Technically, I am helping you, not them. But this constant desire to know the why of things grows tiresome. I don't want to confuse you. Just know that I have a debt to settle. As long as helping you advances my goal, I will continue to do so."
You're using me? "The look on your face! How precious! You are dismayed. Why should the truth upset you? You benefit from my assistance, just as I benefit from yours. Patience, little mortal, you shall see. Now off with you. Nothing will come of us standing here."
What can I expect inside the Citadel? "Death, most likely. The kyn that guard this Citadel will try to kill you. It's generally what we do. The old hall you seek is near the main gate. If I were you―and, most thankfully, I am not―I would make my way in there posthaste."
"Only those of Daedric blood may enter the pyramid, little mortal."
Can you open the way for us? "I told you that you'd need my help. A Daedric ritual locks this door, and only a willing offering of kyn blood will open it. I am your key to Valkynaz Seris. You are my key to vengeance."
Will you help me in the coming battle? "That I cannot do, little mortal. If the Valynaz is banished by my hand, I will lose honor and standing. If you kill him, however, I remain true to my word. And Seris abides in the darkness with my lost clan until Coldharbour allows him to return."
Why do you seek vengeance? "My clan was destroyed. Erased from this existence. And the hand that orchestrated that destruction was Valkynaz Seris. He thought my clan was a threat to his power. Whatever the right or wrong of it, Seris must pay for what he did."
I'm ready. Open the door. "Well, little mortal? What are you waiting for? Must I hand you an engraved invitation? Get inside and do what you came here to do!"
"Even by kyn reckoning, I have waited a long time send Seris into the darkness. Allow me to savor this moment, little mortal."
So, now you're the Valkynaz of the Citadel? "What possible interest could that be to you, little mortal? Let me guess. You're worried that now I will order my kyn to destroy you. I assure you, a change in leadership can be a time of confusion. No harm will come to you or yours―for now."
Are you happy now that Valkynaz Seris is dead? "Kyn do not die. Seris has been banished to the darkness. Long ago, our clans were locked in war. Seris, through treachery, banished my clan. Everyone but me. I accepted a blood oath to remain free, promising that my hand would never harm him."
But you asked me to slay him. "I remained true to my oath. I helped you enter the pyramid. Nothing more. Indeed, the ingominy of a mortal sending Seris to the darkness was most gratifying."
Will you help us assault the Endless Stair? "My goal was revenge. I have no interest in your squabbles. Understand, little mortal. A kyn's desire to spill mortal blood never ebbs, even if we don't always act upon it. I am what I am. If we meet again, I will smile as I take your life."
"You proved very useful and earned the assistance I provided you. But I wouldn't recommend lingering in my territory, little mortal. I cannot vouch for the patience or control of my newly awakened kyn."
"A mortal wandering here of its own volition? And it can fight! A daring soul! Perhaps you'd like to help me complete my day's work. I seek to attack this prison, lay low the Daedra who run it."
Why would I help you? "Why does your kind do anything? Perhaps you want to see what spoils you can mine from this place. Or maybe you want to help the mortals trapped deep below. Your kind has such baffling sensibilities."
There are people trapped here? "So many! Held for torture, for parts. For amusement. You can't hear the screams from up here, but I assure you they are uttered."
I'll handle this. "I'll lead you to the prisoners if you'll assist me in my day's butchering. Information has a price, little mortal. Head inside, slay the Overfiend, and anything else that bars our way to the inner halls. Then we'll talk."
Why do this? You're a Daedra. "And? Mortals kill mortals, do they not? I see it every day. Such atrocities you commit against each other given proper incentive! We do the same. We do it better."
Who is this Overfiend? "He was like you, once. Mortal and small. But the aura of this place changed him. You'll see. His death is necessary if we're to reach the inner halls."
Defeating him will allow us to free the prisoners trapped below? "You'll find plenty of prisoners to free if you survive. Perhaps they can serve as distractions as we move deeper. Every Daedra here will come to stop you, little mortal."
What happened to this prison? "It holds prisoners as it always has. But the torture chambers below have been made exquisite. They belong to Lord Bal now, run by his... trusted lieutenants. It should have been my clan in charge."
What do you mean? "One thing at a time, mortal. Let's see how far you get. The Overfiend is waiting."