Bloodline

Walkthrough
After being sent to investigate the goings on in Dimhollow Crypt by Isran, the Dragonborn discovers a strange guarded sarcophagus, inside of which a vampire woman named Serana had been sleeping for several hundred years. Unlike other vampires, she is not hostile, carrying an Elder Scroll. After a bit of catching up on world events, she realises that she has been away for far longer than she initially anticipated and asks the Dragonborn to take her home to Castle Volkihar.

Lead Serana to her home
The Dragonborn then leads Serana home, using a boat at Icewater Jetty to reach the Castle Volkihar.

Speak to Harkon
Once inside, the party proceeds to a large banquet hall where Lord Harkon greets them. Harkon thanks the Dragonborn for returning his daughter with an Elder Scoll and offers his own blood as a reward, explaining that taking the blood will transform the recipient into a vampire. He also mentions that should the Dragonborn refuse the gift, permanent banishment from the castle will result and the Dragonborn will forthwith be considered a prey.

Return to Isran
If the Dragonborn chooses to stay loyal to the Dawnguard, return to Fort Dawnguard and report on the findings at Dimhollow Crypt.

Blutlinie