Ancient Power (Dawnguard)

Background
Feran Sadri sends the Dragonborn to retrieve the petrified remains of an elder vampire from a radiant location. This quest can be repeated up to four times. Body parts include:
 * Head
 * Ribcage
 * Arm
 * Hands
 * Leg

Walkthrough
Head to the radiant location marked in the journal, the bodypart will typically be located within in a chest.

Possible locations

 * Volunruud
 * Dead Crone Rock
 * Gallows Rock
 * Witchmist Grove
 * Halted Stream Camp
 * Lost Echo Cave
 * Shimmermist Cave
 * Geirmund's Hall
 * Lost Knife Hideout
 * Orotheim
 * Halldir's Cairn
 * Serpent's Bluff Ruins
 * Sightless Pit
 * Harmugstahl
 * Ansilvund

Reward
After infusing the remains' lingering magical essence into the Bloodstone Chalice, the Blood of the Ancients ability granted to the Dragonborn will last for a longer duration of time:

If the ability was already listed under active effects, it will be removed upon completion of the quest as it becomes obselete. The upgraded version of the ability can then be obtained from the chalice.

Reward

 * 3 x Potion of Blood