Unlike most companion quests, this one can be completed during Act 1 or Act 2.
Head towards the Kirkwall Chantry in Hightown, before the Chantry board: a cutscene will play. It will show Sebastian posting a notice on the Chanter's Board offering coin in exchange for the deaths of the mercenaries that killed his family. Read it and accept the quest and head to the Docks (Night), Sundermount, and Wounded Coast areas.
You can do these areas in any order you choose, however it is easier if you head to that area when other quests lead you to it.
- Docks (Night) - When entering from the north, the first alley on the right.
- Sundermount - Just around the corner when entering from the World Map.
- The Wounded Coast - Take the first right, and then follow the next path on the right.
Once all 3 groups are dead, head back to the Chantry and talk to Sebastian to complete the quest.
Sebastian will reward you with 4 and you will also receive 400xp for completing the quest.
The Flint Company Mercenaries drop the following items:Flint Company Cuirass
Requires: 20 dexterity
+5% critical chance (looted from the Sundermount group) Meghan Vael's Locket
+184 fire resistance
+184 cold resistance (looted from the Wounded Coast group)
Completing Duty leads to the Repentance companion quest, which is available in Act 2, if you are already in Act 2, you may play it immediately.