There are 4 total doors in the Celestial Nexus all with the same name; one after another. The fourth door is the final door and leads into the BC. Do not open this (the fourth door with the sirens in the room) door until you are ready to begin the BC. There is no actual Burning Circle to stand on to enter.
Group up with your party if you have not already and enter the battle field. Once you enter, you cannot flee from the battle.
If you do need to leave, just die. After being kicked from the BC you will reappear at the entrance of the Celestial Nexus. If you wipe, you will not go to Hall of the Gods.
Buffs WILL wear upon entry
Watch the final cutscene and prepare to battle Eald'narche, who has two forms.
Orbitals x 2 - have ~130hp and if defeated; they are resummoned quickly. Lullaby works rarely (detector mobs are very resistant, but not entirely immune to it), but Sleep is recommended due to being vastly more reliable.
Exoplates - the armor surrounding Eald'narche. It has about 10000 HP. It does not do melee attacks. Special attacks:
Headbutt is GREAT at stopping all of his ancient magic for both his first and second form, I highly recommend it.
Once the exoplates are gone he has only about 2000 HP.
Suggested strategy - have melee use 2 hour specials to quickly dispose of the Exoplates, while mages stay far enough to avoid being hit by Phase Shift. Sleep the Orbitals as they're not worth attacking. After the Exoplates are gone it only takes a few hits to get Eald'narche to his second form. There is very little time to rest before the second form. Consequently, after the Exoplates are killed, do not immediately attack Eald'narche but rest and recover HP, MP, status (and raise weakness if need be) before finishing off the first stage of the fight.
Eald'narche can EASILY be tanked with /NIN by anyone with a strong hate tool (Provoke, Flash, Ninjustu spam, etc). Keep haste up on tanker.
Try to avoid doing anything to Eald'narche until the Exoplates are gone; in particular, pull the Orbitals away before using Sleepga. Let your tank get initial aggro and then tank that way.
Note that if all the frontliners do not have Utsusemi, burning down the Exoplates quickly as advised above will result in a lot of damage (and likely death) due to Phase Shift spam (which is triggered by Exoplates HP). A wiser approach in such a situation would be to do damage until just before triggering a Phase Shift, then have all melees turn around. Heal up, do damage to trigger the Phase Shift, recover from it, and proceed, repeating for each of the three Phase Shifts.
If you wipe, don't bother to Reraise; you will get aggro wherever you are on the battlefield.
Second form Eald'narche is still pretty weak (~2500 HP), but more annoying.
He will teleport at the spot where you reappear after the CS within about 20-30 seconds. So be prepared to kite or not have anyone rest after CS.
He teleports around like Ark Angel TT.
In addition to his ancient magic and Sleepga II, he casts Bindga (and other debuffs?)
He has a very high melee resistance cut damage by about 75% (Rampage for 200-250~).
He may also have 75% magic resistance (as Thunder IV was seen to consistently do ~300 damage)
All Tier II Ancient Magic damages this form of Eald'narch for 850~. Keep your tank alive and a BLM with Tier II Ancient Magic can kill Eald'narche on his/her own.
Tanking is hard, hate seems to moves around randomly. (Jan 27th, 2008 - Tanking was very easy both times this was completed; hate never wavered off of tank using the above Tier II Ancient Magic method.)
Eat Poison Potions and consider stunning some spells.
This battlefield becomes very easy if all players sub Ninja (including mages). Utsusemi can negate a lot of the damaging TP attacks and spells.
Ealdadork is alittle difficult. I went 1/4 on him. I find that having a SMN in the group helps with the DD, a BLM is a must because of the gunpods that pop. Need to have a well geared tank and heavy DD and a refresher. That's the safest way to kill him.
After dieing here we experienced no exp loss from raises