You MUST have learned Krombral (Giant-language) or you will not be able to zone into the Oratorium Of Thyr and will not be able to reach Nagafen for the final portion of this quest. When traveling from the top of the zone to the Oratorium there are approximately enough Giants to drop enough Giant Idols get two members of your party all six necessary idols.
Starting the Quest
Approach the ravine in Lavastorm that leads to the entry to Maiden's Gulch and speak to Sebir the Historian, ( -168, -10, -546 ) Copy/waypoint -167.86, -9.63, -546.37who tells you about the sage who needs rescuing.
Kill the Drakota Inquisitor and Vyr'drais the Vicious (51^^^ Heroic, no longer Epic) with 2 adds, and hail the Sage of Ages on the platform behind him to start the quest.
Steps
Once you've started the quest with the Sage, travel to the bottom of Solusek's Eye (sublevel 6), (where translucent paths wind over the lava) and enter the The Oratorium of Thyr ( -202, -617, -198 ) Copy/waypoint -202, -617, -198.
To get to the paths which lead to the Oratorium you will need to take a lift ( -325, -595, 187 ) Copy/waypoint -325, -595, 187 to the third floor in the Giant Apartments, but it may appear that you can only travel up to the second floor. To get to the third floor, open the door once you arrive at the second floor and hit the "up" option on the triangular button just inside the door (you may need to run into the room and back to the lift, but there is a short delay on the lift which should allow you to do so before the lift moves up to the third floor).
Just before you reach the Oratorium there is a ledge you must jump down ( -103, -614, -292 ) Copy/waypoint -103, -614, -292.
Fight your way through the Oratorium (level 50-51^^ giants) to Flame Lord Thyr.
Hail him to spawn two Efreeti minions. Any member of the party can do this, as long as the party is prepared to fight the Efreeti after the hail.
Tip: You must be close to him to get the conversation tree - Target Him and press H.
After defeating the Efreeti minions, have a non-critical party member hail the Flame Lord.
The person hailing the Flame Lord is temporarily banished to a cage from which they cannot escape and will draw aggro from magma elementals in the zone (if they haven't been cleared previously). Note: even if the magma elementals do not aggro (ex: they are grey con) you will need to fight them anyway once banished to the cage.
The person doing the hailing should obviously not be your main tank. Conjurers, Necromancers and Illusionists are able to use their pet while in the cage. It is also possible for some classes to cast down on the Flamelord and to heal from the cage.
If you can solo the Flamelord, it is possible to range pull him to the cage (or root him to a safe distance) and complete the instance solo, but the task can be difficult. Use a Longbow and +5 range Field arrows. Monks can also solo this at level 80, Peel is capable of hitting the Flame Lord while in the cage. It is also possible for pet classes to solo.
After the Flame Lord is defeated, the person in the cage is immediately teleported to the back door from the cage.
Exit the Oratorium using the Doorway BEHIND where you initially hailed Tyr to proceed on to Nagafen's Lair.
Because you do not know the Elder Dragon language (the whole point of this quest is to learn it), you can't speak to Lord Nagafen once you enter.
Speak to Majordomo Inferinus who tells you that you need to learn the language Elder Dragon to be able to speak to Lord Nagafen.
Speak to the Sage of Ages in Antonica on the top floor of the Tower of the Oracles. He tells you that you need to find 26 translated runes of Elder Dragon to learn the language.
On a bookshelf across from the door ( -127, -32, -140 ) Copy/waypoint -127, -32, -140, you get access by clicking on a grate in the floor at ( 5, -26, -121 ) Copy/waypoint 5, -26, -121 on the second level down in Stormhold.
Go inside the tent behind Merchant Murgina and look up. The scroll is standing on its end next to the center pole ( -149, 14, 188 ) Copy/waypoint -149, 14, 188
Runes #1 & #2: You will have to complete the access quest Summoning the Creator in order to unlock the door leading to the lower levels.
Rune #3: You will either have to complete the access quest Entrance into the Obelisk or use the Feerrott zone-in which puts you just inside the Obelisk.