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Elder Scrolls Online - Soul Shriven in Coldharbour Walkthrough (Part 2)
http://www.rarityguide.com/articles/articles/5609/1/Elder-Scrolls-Online---Soul-Shriven-in-Coldharbour-Walkthrough-Part-2/Page1.html
By Douglas Shepard (Editor in Chief, RarityGuide.com)
Published on 03/11/2014
 
A Walkthrough of the quest "Soul Shriven in Coldharbour ", in the Elder Scrolls online. This covers reaching the Coldharbour Sentinel, attempting to reach the Prophet then talking with Cadwell and reaching the Undercroft.

Elder Scrolls Online - Soul Shriven in Coldharbour Walkthrough (Part 2)

Quest objectives covered in this part:
Talk to Lyris
Reach the Towers of Eyes
Destroy a Coldharbour Sentinel
Talk to Lyris (optional step)
Reach the Prophet's Cell
Talk to Lyris Titanborn
Talk to Cadwell

Lyris Titanborn stands before you. She will ask about the man who told you to find her. She will explain more about the Prophet and that is was very dangerous for him to contact you however briefly. She will also explain that you were killed by Mannimarco in honor of Molag Bal. The remains of your soul were sent here. She will explain that you need to head for the Towers of Eyes. There you can find the Sentinels of the area. Disabling one of them should let you find a way through to the Prophet. Follow the other Soul Shriven as they leave the area.

Once you are outside, you can talk some more with Lyris. That part is up to you. After that it is time to hunt down the Coldharbour Sentinel. Head down the slope to the South. Cut across the river and head on up the ramp opposite you.

Ramp Entrance to Sentinel

Be wary of the Flame Atronachs and the Feral Soul Shriven. For this part, more the Atronachs than the Soul Shriven. Head on up to the top. There you will find the Coldharbour Sentinel:

Coldharbour Sentinel

Go over to it and interact with it. This will disable the sentinel. Head to the North, down the ramp that you just came up. Turn to the East then head to the South. Take the stairs on up to the door. This is the entrance to the Prophet's cell. Approach it. Lyris will come running you to.

Entrance to Prophet's CellColdharbour Sentinel

The problem is that this also triggers a fail safe that cuts off the direct path to the Prophet. You need to go and find the Soul Shriven Cadwell. He has been in Coldharbour for a long time. It seems like he was not too sane to begin with.  For this reason he seems to have adapted to Coldharbour very well. Head down the stairs you came up and go over to the East. You will see some Shriven gathered around a fire. Approach them. One of them has an iron pot on his head and is singing about 2 knights very nonsensically. This is Cadwell:

Cadwell

He will explain that there is a second way into the Prophet's Cell. He also explains that is means a lot of “fun”. You just need to follow the river and it will lead to the Undercroft. From there it is a simple matter of staying to the light and finding a ladder. That ladder will lead you directly to the Prophet.

Head over to the River to the Northeast of you. Follow it to the South to reach the Undercroft. En Route expect to encounter a few Flame Atronachs. The river will lead directly to the Undercroft before too long.  Turn to the right as you see a break in the river. This will lead you  to the entrance of the Undercroft.

Entrance to the Undercroft