This quest is acquired after opening the first gate in the Darkspawn Warrens. From there, you will find a further eight gates, each of which requiring various numbers of ancient gears to open. All of the gates are easily found along the main thoroughfares of the Deep Roads.
First Gate - Requires 3 gears
This gate leads to a cavern containing numerous darkspawn and a minor boss named The Reveneant. This boss behaves like a darkspawn emissary and shouldn’t cause much trouble, but you’ll want to take out the weak darkspawn before focusing on it.
Location: Found along the path shortly after passing the initiating gate.
Second Gate - Requires 3 gears
This gate leads to a cavern containing four Hurlocks which are easily dealt with. You can take a shortcut to the Ruins of Heidrun Thaig at the other end of the cave once you’ve cleared the area.
Location: South west of the first lift in the Ruins of Heidrun Thaig.
Third Gate - Requires 4 gears
There are no enemies contained beyond this gate, but there’s plenty of loot and another ancient gear.
Location: Directly opposite the second gate.
Fourth Gate - Requires 4 gears
As you enter the cavern beyond this gate you will be ambushed by a darkspawn Emissary and a few lesser darkspawn. They shouldn’t pose much of a threat and you will find plenty of loot once they’re dead.
Note: This gate can only be opened once the Expedition Table operation ‘Deep Roads Expeditions: Heidrun Thaig Upper Bridge’ has been completed.
Fifth Gate - Requires 4 gears
The cavern beyond this gate contains a number of lesser darkspawn which are easily defeated. You will be able to establish an expedition flag once everything is dead.
Note: This gate can only be opened once the Expedition Table operation ‘Heidrun Thaig Lower Bridge’ has been completed.
Sixth Gate - Requires 4 gears
This gate leads to a small cave which contains two Genlock Alphas. You can lead them back out of the room to fight them with more space if necessary.
Location: In the eastern section of the darkspawn nest which is ravaged by fire during The Descent.
Seventh Gate - Requires 5 gears
The cavern beyond this gate contains numerous darkspawn Stalkers. These can be deadly unless you take them out quickly with powerful area of effect damage.
Location: In the northern section of the Legion of the Dead Camp in the Ruins of Heidrun Thaig.
Eighth Gate - Requires 5 gears
The cave beyond this gate contains some corrupted spiders, which are easily defeated.
Location: Within the Ruins of Heidrun Thaig, near the central bridge.
Ninth Gate - Requires 5 gears
This gate is not marked on the map until it has been opened. Head to the large dwarven statue at the south end of the central bridge in the Ruins of Heidrun Thaig. To the left of an entrance to the cavern behind the statue, you’ll find a narrow passage. Follow this to find the gate beyond. There are no mobs within the cave.