It Comes From Beneath

It Comes From Beneath is a quest that takes place in Vigil's Keep.

Journal Entry
Eradicate darkspawn beneath the Vigil
 * Sergeant Maverlies reports possible pockets of darkspawn beneath the Vigil. You can ask Maverlies to escort you to and from the basement.

Walkthrough
This quest is initiated by talking to Sergeant Maverlies, who is standing in the courtyard near the door to the basement. She will explain that the explosions during the assault on Vigil's Keep caused some damage to the lower tunnels and that there are now darkspawn in the basement. If you agree to take the quest, she will escort your party downstairs.

Vigil's Keep - Basement
Go down the stairs into the large room with dead darkspawn. There is an injured mabari on the ground with a note attached to its collar. If the Warden, or a companion, has high enough survival skill (rank 3 or expert survival), they can calm the dog and gain +2 approval from Nathaniel. If not, you can inspect the note, which begins the quest Adria's Plight.

Continue down the hallway, where you will encounter groups of darkspawn. The small rooms on each side of the hallway can be looted for various treasures. In the second room on the left, there is a statue of Andraste that you can inspect to receive a message. The inscription mentions seeing through a flame. Once you have examined the statue, the torch immediately to the right of the statue becomes selectable. Examine the torch and a secret room with a chest is revealed.

In the next large room, Darkspawn-infected prisoners will attack as soon as you enter. There are a few prisoners still alive, whom the Warden can release, leave in prison, or kill. Releasing the prisoners naked will gain you +5 approval from Oghren. If you spared Nathaniel, he is able to pick the lock on the Crypt door on the right.

The Family Crypt is in the room to the left of the prison. Head through the door and loot the sarcophagi along the top level since heading down to the lower level will trigger an attack by ten undead. The sarcophagus on the lower level can be looted without any risk of attack after that first spawn. On the wall facing where you entered, there are four keyholes and two statues, which are part of The Wraith's Vengeance quest line. The statues can be examined to receive codex entries. One key is in a sarcophagus on the lower level. The other three keys are found in the area beyond the rubble.

Return to the room with the jail cells and continue moving forward. The next room will trigger a cut scene and the Warden learns what has become of the mabari's owner, Adria. After a brief conversation, she attacks the Warden. Killing her completes the quest.

A pile of rubble blocks the Warden's further progress through the cellar. Dworkin can clear it away, but it will take some time. There is nothing more to do at this point, so accept Maverlies' offer to return to the courtyard.

Vigil's Keep - Deep Roads
The Warden will have to leave Vigil's Keep for some time in order for the dwarf to get the work done (just visiting City of Amaranthine and even doing side-quests there won't be enough). Upon returning, speak with Sergeant Maverlies and she will inform the Warden that the rubble has been cleared away, revealing a tunnel that is connected to the Deep Roads. In order to prevent anymore darkspawn invasions, the darkspawn need to be cleared out and the Warden will have to find a way to block the tunnel off. Head into the tunnel, checking the rooms to either side of the main path. The first room to the right contains a dead darkspawn with a statue on the corpse. Loot the statue and head to The Shrine of Korth, where the tier 8 battleaxe Frenzy can be obtained, see The Shrine of Korth for details.

Backtrack to the crossroads and continue down the other path, fighting darkspawn along the way. A room on the right has Lyrium Sand and the one to the left a hidden chest with a lock on it, which contains one of the keys for the Family Crypt (the other two can be looted from darkspawn). Note : Only ONE of the keys (the key to the crypt itself) required for the side-quest "A Wraith's Vengeance" (in the Howe Family Crypt) is found on a darkspawn (1 in a sarcophagus in the crypt itself, 1 in an urn of the Shrine of Korth area, 2 in locked containers in the DeepRoads section of Vigil's Keep)

There is a wraith in the next room, who will be reinforced by five undead. When you get the wraith's health down to a low level, it will disappear, initiating the quest The Wraith's Vengeance. Selecting the center statue will allow you to proceed. Continue down the hall, where, after a battle with an ogre and other darkspawn, the wraith will possess the dead ogre's body. Once the enemies are dead, a cut scene will commence showing the dwarf repairing the gates to the deep roads so that they can be sealed.

Result
The Keep is secured from below.

Endless experience exploit
It is possible to trigger an infinite experience exploit with this quest. Although the exact requirements are unclear, if Sergent Maverlies is waiting outside for the rubble to be cleared, you can go down to the rubble by yourself. She will still be there with the dwarf. Talk to her and tell her that you want to go back to the surface. You get about 2000 experience points over and over again.