Also a new save sphere appears in the first chamber. Save your game and prepare for....
Spectral Keeper
HP - 52,000
AP - 12,000
Weakness - None
Steal - Ether, Turbo Ether
This battle pretty hard. You have the option of moving to different circles. Summon your aeons and use an overdrive, then they die from glyph mines. Now, if you use all of your aeons, The Spectral Keeper probably wont die. So then have one person in front of the boss and 2 in the back of him so only 1 person gets hurt. Make sure that person has Protect, Berserk Ward, and Hastega. Just do what I said to do, and you'll win for sure....maybe. Sometimes you got to have your luck.
Follow the party into the temple. Then you need to speak to Yunalesca. Very, very long video you need to watch. Save your game and. . .
Yunalesca
HP - First Form: 24,000; Second Form: 48,000; Third Form: 60,000 AP - 14,000
Weakness - Ice
Steal - Stamina Tablet, Farplane Wind
This battle is extremely easy at the end and tough in the middle. We'll go through it stage by stage.
1st form:
Yunalesca will counter on all of your attacks in this form. But, her attacks are weak so your fine. Yippie! Physical attacks will be countered with Darkness, Magic will be countered with Silence, Special attacks will be countered with sleep. So, now that you know this, be prepared to heal your party members each attack. This form is quite easy, so just attack her and heal your party members.
2nd form:
Yunalesca has a new attack this time around, Hellbiter. Use Holy Water on your party members to prevent Yunalesca from hurting them with cure magic. Use Haste on the whole party. And near the end of her HP, keep a few party members with zombie. Sounds weird but oh well.
3rd form:
A very easy part, if you have lots of Phoenix Downs and keep zombie on. Summon your aeons and annihilate Yunalesca with their Overdrives. Then when she casts Mega-Death, you wont be dead if you have zombie status on.
Search for the Sun Crest then head to the Airship by leaving the dome.