You get this after defeating Rubicante in Tower of Babil when entering from the cave of Eblan, so second trip into the tower. The boss is quite standard, obviously stay away from fire attacks, You have two options either grind him down without using ice or water attacks. or keep a close look on which state he is in. if he has his cloak wrapped around him he will absorb and heal from these attacks if he has it open it will be his weakness taking double damage.