Xan Bie is the God-Beast of fire. It appears as a boss in Seiken Densetsu 3 and is comprised of many flames that can form various shapes. Though it is assumed to be sentient, Xan Bie doesn't display any personality aside from a desire or instinct for destruction.
Xan Bie was described as being an "incarnation of disaster" that existed before the world had been fully born. It wrought destruction on existence until the Goddess of Mana defeated it with the Sword of Mana and sealed it away inside the Mana Stone of Fire.
When the villains in Seiken Denestsu 3 obtain the Sword of Mana, they release the God-Beasts from the Mana Stones. Once released, Xan Bie remains near the former location of the Fire Mana Stone in the Valley of Flames in order to build its strength in preparation for wreaking havoc across the land. As a result, the God-Beast becomes stronger depending on how many of its brethren the heroes have defeated before they challenge it.
Returning to the Valley of Flames, the heroes find that they can enter a path that was previously closed to them; this path eventually leads them to Xan Bie. The God-Beast will take multiple forms during the battle and will use different attacks based on its form. At the very top of the arena is a furnace-like structure; after taking considerable damage, Xan Bie will retreat into the furnace in order to heal itself. The heroes can destroy the furnace in order to prevent this, however.
As a Fire-elemental creature, Xan Bie is weak to Water-based attacks and magic. It is also healed by Fire-based attacks and magic.
Heat Beam (one)
Fireball (all) - Level 1 Fire spell
Explode (all) - Level 2 Fire spell
Blaze Wall (one) - Level 3 Fire spell; can also cast on self for recovery
Flame Saber (one) - Casts on a party member to change his/her attacks to Fire-element, causing all physical attacks to heal Xan Bie
Power Up - Raises attack; casts on self at 1/4 HP
Lava Wave (all)