Altar of Dumat

The Altar of Dumat is an optional side quest in the Legacy DLC for Dragon Age II. It involves the collection of four ancient Tevinter artifacts, then deciding whether or not to use the artifacts to perform a ritual in honor of Dumat, an Old God.

Acquisition

The quest can be acquired in Corypheus's Prison – Farele's Floor or Corypheus's Prison – Tower Base. It is received when Hawke finds any one of the four artifacts listed below.

Walkthrough

All of the Tevinter artifacts must be acquired to perform the ritual. They are found in the following locations:

Crown of Dumat is found in a side-room on the east side of Farele's Floor.
Dumat's Sacrificial Dagger is found in a side-room on the northeastern side of Farele's Floor.
Dumat's Ritual Scroll is found just north of Dumat's altar. Locate the two sets of stairs forming an 'L' shape; the scroll is on the upper platform.
Sacred Urn of Dumat is found in the clearing after the area in which the Altar of Dumat is located (in the Tower Base). It is in a small cave just to the south of where Hawke battles deepstalkers and spiders.

(Note that the fourth artifact is located beyond the Altar of Dumat, so Hawke may only have three out of the four artifacts when first encountering the Altar.)

The Altar of Dumat itself is located in the third main clearing in the Tower Base, which is up the carved stone steps on the opposite side of the clearing, having passed through the gap between the two griffons statues.

Hawke has two options at the altar: either defile it, or place the four sacrifices. Both options are available until the fourth object is placed (which causes the quest to complete). If Hawke wishes to defile the altar, it must be done prior to placing the last sacrifice. Note that taking either option completes the quest successfully, and counts towards the Tower Sweeper achievement.

Altar of dumat-3-of-4 — All four sacrifices placed on the Altar of Dumat

Result

If Hawke decides to defile the altar:

Hawke fights two rage demons and six shades, receiving random treasure from the demons.
Fenris: friendship (+5)
Sebastian: friendship (+5)
Anders: friendship (+5)
No change with Bethany, Carver, Aveline, Merrill, Isabela, or Varric.
Journal updates: "The altar is defiled and its demons slain. Its powers have ceased."

If Hawke places all four sacrifices:

Fenris: rivalry (+10)
Sebastian: rivalry (+5)
Anders: rivalry (+5).
Merrill: friendship (+5)
Isabela: friendship (+5)
No change with Bethany, Carver, Aveline, or Varric.
Journal updates: "Sacrifices made at the altar of Dumat appear to have pleased the old god. The altar now appears dormant."

Rewards