Assault on the Stronghold

Objectives

 * Roan Fierceheart in Dalada Uplands will prepare you for the assault. (disappears from Quest Log after speaking to Roan)
 * Invade the hierophant's stronghold and rescue the Ebon Vanguard.
 * Defeat the Charr guards and gain control of the siege devourers.
 * Target archer groups with siege devourers to cover the armored saurus while it breaks down the front gates.
 * Free the Ebon Vanguard held captive within the fortress.
 * Defeat Hierophant Burntsoul and all hostile forces.

Obtained from
 * Automatically added upon completing What Must Be Done
 * After first completion, can be obtained from:
 * Roan Fierceheart in Dalada Uplands
 * Scrying Pool in Hall of Monuments (select "I seek guidance" option)

Requirements
 * What Must Be Done

Walkthrough
Speak to Roan Fierceheart outside Doomlore Shrine to initiate the quest. You will be transported to Sacnoth Valley.

The first stage of this quest involves capturing a pair of Siege Devourers and using them to take out Charr Seekers on the walls of the stronghold so that the Armored Saurus can move up to the gate and break it down. Pyre's warband will capture the right devourer, although they will need some assistance in hard mode. You can tell the devourers to target either the bluff or the gate on that side. Trios of Charr warriors will spawn below the bluff and attempt to kill the devourers, while the seekers on top will respawn continuously. If the saurus dies, it will also respawn behind the devourers after a few seconds.

One way to handle all the Charr here is to set both devourers to target the gate, then move your party to the center of the area where you can target the seekers on both bluffs. Your healers can also help keep the saurus alive from here. The warriors on the right can be ignored, as the warband can handle them, but be sure to intercept the warriors on the left. It's also possible for a minion master to handle the warriors alone, letting the rest of the party focus on the seekers.

Alternatively, and especially in hard mode, it may be easier to assign a healer in the party to keeping the saurus alive, while the rest of the party defends the devourers. A bonder can be quite effective at defending the saurus.

After the gate is down, clean up any leftover warriors and seekers before moving into the stronghold. A mass of Charr awaits you, but they will retreat when you enter the gate. Take out the few groups of Charr left in the outer area before moving into the central area. If the saurus is still alive, it will move up to the base of the stairs, and can provide additional support at this point.

Move up the stairs to trigger the dialogue, but do not aggro any Charr. Once the Destroyers have been released, fall back and let the Charr and destroyers slug it out. In normal mode, the Charr will invariably lose, but they will often win in hard mode. To help the destroyers win, you can aggro the nearest group of Charr while the dialogue is playing and pull them down the steps.

After the area is cleared of both Charr and destroyers, a cutscene will play, and the party will appear in Grothmar Wardowns just outside Longeye's Ledge.

Allies

 * Charr
 * 20 Bonwor Fierceblade
 * 20 Roan Fierceheart
 * 20 Cowl Fiercetongue
 * 20 Gron Fierceclaw
 * 20 Seer Fiercereign


 * Devourer
 * 20 Siege Devourer


 * Dinosaur
 * 28 Armored Saurus

Monsters

 * Charr
 * 20(26) Charr Bladestorm
 * 20(26) Charr Axemaster
 * 20 (26) Charr Elite Guard (Warrior)
 * 20(26) Charr Seeker
 * 20 (26) Charr Elite Guard (Ranger)
 * 20(26) Charr Avenger
 * 20(26) Charr Prophet
 * 20 Charr Wardkeeper

Bosses

 * Charr
 * 29 Hierophant Burntsoul (Ether Prodigy)

Dialogues
Briefing from the Scrying Pool.