Judgment Day!? 99,999 damage to all!? WTF!? How the hell do you escape that!?

I know! Using the Aeons as meat shields!

And 12,000,000 HP!? Oh good God... *Faints*

Oh yeah, here are Penance's stats which I found in square-central.com

Penance

HP: 12,000,000
AP: 60,000

Strength: 255
Defense: 240
Magic: 255
Magic Defense: 200
Agility: 255
Luck: 10
Evasion: 0
Accuracy: 255

Penance Arms

HP: 500,000
AP: 10,000

Strength: 200
Defense: 200
Magic: 150
Magic Defense: 200
Agility: 150
Luvk: 10
Evasion: 120
Accuracy: 255