How the hell do I kill (SPOILER)Empyrea? This thing can't fricken take damage. What's the rutine to defeat this sucker.

My character levels and equips

Hero: 35
Miricle Sword
Dragon Shield
Ring of Clarity
Pirate's Hat
Magic Armour

Yangus: 33
Iron Headgear
Flame Shield
Bandit Axe
Slime Earrings
Bandit's mail

Jessica: 32
Spiked Steel Whip
Flame Shield
Magical Hat
Magic Bikini
Gold Ring

Angelo: 34
Magic Armours
Mighty Armlet
Power Shield
Mythril Helm
Mercury's Rapier