You need to kill this boss (the moving one) four times.
Drop: Asura Broken Arm
Quest "Revenge for Explorer"
Archilles - Commander-Xu
(401 512)
Water Melee
Level ? 4.000.000 HP
This boss has a physical aoe and an aoe debuff (reduce max HP)
Drop: Archilles Horse-Thorn
Quest "Request of dormitive"
Atlantean-Xu
Lot Mode (413 525)
No elt Melee
Level ? 4.000.000 HP
He has four buff (increase his patk, matk, pdef and mdef)
Drop: Great Ape Tail
Baresark Beast-Xu
Lot mode (380 509)
Metal Melee + Magic
Level ? 3.223.518 HP
Drop: Great Ape Steel Mane
Elf of Seven Shine - Xu
Lot Mode (401 525)
No elt Melee + Ranged
Level ? 5.000.000 HP
When his life go under 75% (a minion appeared).
When his life go under 50% (two other minion appeared).
When his life go under 25% (three other minion appeared).
Drop:
• Seven Shine's Quoit
• Astral Stone
• Elf of Seven Shine Strength
Quest "The real fear"
Ancient Belial - Totally Ruin
Lot Mode (401 530)
No elt Melee + Ranged
Level ? 4.200.000 HP
After a few hit three minion appeared (a ranged, a magical and a melee)
He has a random aggro (with a front physical aoe and an aoe debuff: increase casting time)
He has four buff (increase his patk, matk, pdef and mdef)
When he has less than 25% hp:
• he has a mana burn and debuff (decrease accuracy)
• he has more random aggro
Drop:
• Ancient Belial's Horn
• Devil Dusk
• Ancient Belial's Soul