Blackpowder Promise
You get this quest on your way to the Wounded Coast or Sundermount from Javaris, a dwarven merchant. Travel to the Wounded Coast and head towards the Northwest area till you see some stairs on the mountain. You will encounter a Tal Vasoth warrior asking you to fight his people ahead. Go up the stairway and climb the path. Watch for Tal Vasoth ambushes along the way. Enter the Tal Vasoth cavern. Head south in the cave, defeating the enemies along the way. After you defeat the Tal Vasoth in the final cavern, go back to Kirkwall and visit the Docks during the day to talk to Javaris and Arishok to wcomplete the quest.
The Way it Should Be
This is an Aveline Companion Quest. You get this after completing the quest "A Friend in the Guard" and finding Aveline in the Viscount's Keep Barracks. Make sure Aveline is in your party, then exit the city and head to the Sundermount Ambush Site. Travel Southwest, fighting your way through groups of raiders. After you've defeated the final ambush party, report back to Jeven, Aveline's captain, in the barracks. Then check the duty roster near Jeven's room. Then go to Lowtown at night. Locate Guardsman Donnic and kill his attackers. Head back to the Keep to finish the quest.
Sheparding Wolves
This quest will start at Lowtown at night after you've completed Blackpowder Promise. You will run into Sister Petrice who is seeking to hire someone who knows his way around the undercity. After the cutscene, find and approach her in the Foundry District. Rescue her from her attackers. Then accept her offer and go to Petrice's Safehouse in the NW part of Lowtown. Agree to escort Saarebas and use the trapdoor to go down to the Undercity. There are lots of spiders and traps down there, so watch your step. Exit to the Vinmark Mountain Pass and you will run into a Qunari group who wants you to hand Saarebas over. For max XP and rewards, we recommend you don't hand Saarebas over to the Qunari.. After the fight, head back to Petrice's Safehouse in Lowtown to get your reward and conclude the quest.
Loose Ends
After completing Birthright, read the letter on the writing desk in Gamlen's home. Then go to talk to either Mirran or Athendril.
If you are to meet Athendril, go to the Blooming Rose in Hightown. Then head to the Docks to rescue Pryce from the Coterie. After the battle you have a choice if to send the boy away to start a new life, or to do what Athendril asked you to. Return to the Blooming Rose to conclude your quest.
If you are to meet Mirran, find him at Lowtown at night, in an alley near the entrance to the Hanged Man pub. Then head to the docks by day. Locate Gustave at the SE part of the docks. Decide whether to kill Lord Harimann or not. Then go back to Lowtown after dark to talk to Meeran and complete the quest.