No One Escapes Cidhna Mine

After completing "The Forsworn Conspiracy," the Markarth city guards frame the Dragonborn, starting this quest. The Dragonborn is locked in Cidhna Mine and at one point is given the choice to free Madanach and become a Forsworn or to kill him. As a reward, the Dragonborn can receive either the Armor of the Old Gods or the Silver-Blood Family Ring.

Quick walkthrough

 * 1) Ask a prisoner about Madanach, then get past Borkul the Beast.
 * 2) Talk to Madanach.
 * 3) Speak to Braig and listen to his story.
 * 4) Return to Madanach.
 * 5) Options:
 * 6) Kill Madanach and leave Cidhna Mine through the secret escape path mentioned in Madanach's Note.
 * 7) Kill Grisvar the Unlucky and follow Madanach.

Meeting Madanach
Talk to Uraccen to learn that Madanach is in a private cell which is being guarded by Borkul the Beast. Borkul will demand a shiv as toll. A shiv can be obtained from Grisvar the Unlucky, who is located in the south tunnel. He will demand a bottle of Skooma. This can be acquired from Duach or Braig, through pickpocketing, persuasion, or a brawl. Trade the Skooma to Grisvar in exchange for a shiv, and give the shiv to Borkul to get the key to Madanach's cell.

Alternatively, Borkul can be persuaded, given the Skooma directly, pickpocketed, or defeated in a brawl.

Attacking Borkul outside of the brawl will cause all the prisoners to attack. Unless one is a strong mage character, a Werewolf, or a Vampire Lord, this is not recommended. If a prisoner is attacked, Madanach will attack on sight as well.

The Forsworn Option
Madanach will try to convince the Dragonborn that he and his Forsworn are justified in their actions and sends the Dragonborn to seek out the prisoner Braig and hear his story. After listening to Braig, return to Madanach and he will offer freedom, but he requires proof of loyalty. He requests the assassination of Grisvar the Unlucky, who has outlived his usefulness to the Forsworn Rebellion. After killing Grisvar, the Dragonborn must return to Madanach.

Upon hearing news of Grisvar's death, Madanach gathers the remaining prisoners and leads them to an escape tunnel that runs through the Markarth Ruins. At the end of the tunnel, the Dragonborn's belongings are returned to them by Kaie, and Madanach adds the Armor of the Old Gods as a reward. Once outside, there is a confrontation between Thonar and Madanach. The Forsworn and Madanach charge the city, killing Thonar and all guards (and citizens) in sight. After they leave the city, they will continue running to Druadach Redoubt which will have several friendly Forsworn inside.

The Silver-Blood Option
Kill Madanach in his cell. Sneak so as not to be detected by the other prisoners and guards. It is unlikely that Madanach will be killed with a pickaxe in one sneak hit, however. If the Dragonborn has the Assassin's Blade perk in the Sneak skill tree, listen to Braig's story and return to Madanach. Madanach will instruct the Dragonborn to kill Grisvar the Unlucky. There's a dialogue option to obtain a shiv from Borkul. Once obtained, kill Madanach with a sneak attack with the shiv. The shiv counts as a dagger and thus the Assassin's Blade perk applies, doing 15 times normal damage. Madanach may survive the initial blow, but it will deliver a substantial hit.

Once Madanach is dead, read the note on his body and use his escape route. It is possible to run or sneak past the Frostbite Spiders and Dwarven Spheres in the Markarth Ruins, especially with the help of the Become Ethereal Shout. If the Dragonborn opts to sneak through the ruins, the Throw Voice Shout is indispensibly useful. Alternatively, being a Werewolf, Vampire Lord, or Mage, makes fighting your way out significantly easier. Another option would be to use the Secret Servant power from the expansion to smuggle your equipment into the jail cell for you. Upon exiting, Thonar Silver-Blood will reward the Dragonborn with the Silver-Blood Family Ring and the Dragonborn's belongings. The ring is enchanted so that weapons and armor can be improved 15% better.

Playing Both Sides
Side with Madanach up until the Dragonborn is given the Armor of the Old Gods, which is at the end of the Markarth Ruins right before exiting to the city. After the dialogue and receiving the armor, attack Madanach, turning him hostile. Doing this while close to the door to Markarth will cause his followers to re-enter and attack the Dragonborn. After Madanach and his followers are dead, loot his body and read his note. Then exit out to Markarth and speak to Thonar. It is best to attack Madanach close to the door to Markarth because if not, his followers may not re-enter and it can be difficult to get the Silver-Blood Family Ring from Thonar as Madanach's followers will be waiting outside to attack.

If done correctly, after killing Madanach and the rest of his Forsworn followers inside the Markarth Ruins, the Dragonborn will exit out to a peaceful Markarth with Thonar waiting to speak with them and reward them with the Silver-Blood Family Ring, as well as a pardon from the Jarl. If Jarl Igmund is spoken to afterwards, he will apologize for the wrongful imprisonment. If upon exiting the tunnel there are Forsworn left, it helps to reenter the tunnel so that Thonar is not accidentally hit.

If a skilled assassin, it is possible to break out with the other Forsworn, and stall Madanach before he exits to Markarth. Once alone with him, kill him and search his body. Madanach will be dead, but the Dragonborn won't be blamed for the kill. When exiting to the city, both the Guards and Forsworn will be peaceful towards the Dragonborn, although they will still fight each other — either side can be assisted as both are friendly and will treat any attacks as accidental. Thonar will almost certainly be killed in the fighting before he can give the Dragonborn the ring, but this route still leaves the Dragonborn with the Armour of the Old Gods, an official pardon from the Jarl and a friendly Druadach Redoubt. Although if they are lucky, a conversation may be started up with Thonar when leaving the ruins, and, by quickly skipping through the lines, the dragonborn may receive the ring. It may take several attempts to pull off properly and by reloading the autosave just outside the ruins, can yield different results.

Another way is to stall Madanach and pickpocket him. He turns aggressive and can be killed. A guard will run in but will not attack.

Notable items
There are two main paths for escape, and each carries a reward:
 * Helping Madanach by killing Grisvar gets the Armor of the Old Gods, a full set of enchanted Forsworn Armor (light armor).
 * Madanach's new headquarters at the Druadach Redoubt cave contains more valuable loot, free for the taking, and a map of all Forsworn encampments.
 * Killing Madanach and escaping alone rewards the Silver-Blood Family Ring, providing +15% Smithing.
 * If Madanach is killed after receiving the Armor of the Old Gods and their belongings after leaving the Markarth Ruins, Thonar will greet them outside and give the Dragonborn Silver-Blood Family Ring as a reward for completing the quest.
 * After completing the quest, the body of Eltrys is still in the Shrine of Talos and can be looted for several hundred septims.

Trivia

 * The Dremora Butler can also smuggle in items.
 * When asked about family by Braig, even if the Dragonborn has a family due to the Hearthfire DLC, the Dragonborn will be unable to answer to having a family in Skyrim.
 * Ironically, Cidhna Mine is escaped through a large, extremely visible hole in the wall that leads straight to Markarth. The Markarth guard, however, seem to be fairly aware of it, since the path exits out right into the hands of the owner of the mine himself, accompanied by guards, who were waiting.
 * If the Dragonborn decides to kill Madanach at the beginning and successfully sneaks out through Markarth Ruins without alerting any other prisoners, the mission will be completed. If the Dragonborn decides revisit Cidhna Mine through the ruins, however, one will find that all the prisoners are dead.
 * If Madanach is killed and the Dragonborn is going through Markarth Ruins solo, a good way to beat the spiders and Dwarven machines is to run past the spiders until reaching the last room, where the Dwarven Spheres attack, then lead them back to the spiders to have them fight each other.
 * With a high Pickpocket skill, one can reverse-pickpocket Urzoga gra-Shugurz beforehand and smuggle equipment into the mine though the Dragonborn must be in reach to pickpocket her through the bars as the door instantly shuts as she begins walking.
 * Also, it is possible to shove Urzoga into the mine, whether to pickpocket her equipment or to kill her with the prisoners' help.
 * If the Dragonborn chooses to kill Madanach, and is a Nord, he will say "Come at me, son of Skyrim!", in a somewhat mocking tone.
 * If the Dragonborn wishes to complete the quest but avoid directly killing Grisvar, it is possible to choose the 'Madanach says hello.' dialogue option and wait. Grisvar will panic and start attacking, and the other prisoners attack and kill him.
 * Choosing not to side with any prisoner, it might be difficult to kill them all with just a pickaxe. But there is a trick to it. Walking up on the hanging bridge and waiting for them to stand directly in front of them, the Dragonborn can use the Unrelenting Force shout. The prisoners will then fall off into the pit directly behind the bridge. They can't get out but the Dragonborn can, making it easy to pick them off one at a time. It is also possible to transform into a Werewolf if sufficient progress is made in the Companions' questline, or buy the spell Bound Sword or any spell tome used to summon a familiar beforehand from a court mage.
 * At one point in the mission, the Dragonborn is asked if they have any family, and can respond that they are outside Skyrim, that they are all dead, or that they do not have any that they care to talk about. This is perhaps the only time where the Dragonborn can talk about their previous life. This has changed with the release of the . Serana, arguably the main Dawnguard follower, will ask about the Dragonborn's family during a discussion of Serana's family.
 * When talking to Madanach for the first time, choosing the dialogue option 'How about revenge?' sometimes only causes him to attack. After killing him, the other prisoners will act normally.
 * Despite Cidhna Mine being considered a prison at the start of the mission, completion of the quest will not reward the "Wanted" achievement.
 * If the Dragonborn has a follower, like Lydia, before going back into the Shrine of Talos to get caught, it is possible to give the follower their equipment and ask for it in the mine and then kill everyone.
 * If the Dragonborn originally sides with Madanach and the Forsworn, but betrays them in Markarth, and kills them all with the guards, citizens of Markarth will proclaim how the Dragonborn was seen leaving the ruins with the Forsworn. Some citizens may even congratulate the Dragonborn on siding with the Forsworn, suggesting a certain inclination to the Forsworn.
 * If the Dragonborn has a high enough Sneak, and decides not to side with Madanach, killing/pickpocketing him is not necessary to open the escape route. If he is hit with a ranged spell/ability and the Dragonborn sneaks back down the hallway, he may open the locked jail cell door to the escape route while searching for the Dragonborn. The Dragonborn can then attack him and his followers again and lead them through the ruins so the Dwarven Spheres and Frostbite Spiders can help make short work of them.
 * If the Dragonborn joined the Forsworn but wishing to avoid the Ash Pile issue upon entering Markarth, simply use  command to kill everyone within Markarth, and resurrect Madanach and his allies with   command, and subsequently the citizens after the Forsworn left the city.
 * To avoid many casualties among NPCs (if Forsworn option were taken), save the game after getting your equipment and wait until midnight before going through the door into Markarth.
 * To gain the armor and ring, it is not necessary to kill Madanach's followers in Markarth. They can be killed outside Markarth as well.
 * It is not uncommon for a Dragon to spawn shortly after exiting the city with the surviving Forsworn. This will likely result in the deaths of many survivors as they try to reach Druadach Redoubt.

Bugs
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