From the Super Mario Wiki, the Mario encyclopedia
The Fire Vellumental is a phoenix with fiery feathers and the third Vellumental boss fought in Paper Mario: The Origami King. It resides in the Fire Vellumental Cave located in the Scorching Sandpaper Desert. After the Fire Vellumental is defeated, Olivia acquires its Bibliofold and can then transform into the Fire Vellumental and use its abilities while Mario stands on the correct Magic Circles. Its fire abilities can be used to counter specific bosses, such as the Ice Vellumental and the Tape. Before the Fire Vellumental is fought, it lights the oily water around its arena, setting it all alight. Olivia is visibly awestruck by it, even claiming that it would be sad to see it defeated when it loses all its feathers. It is based on the Vermilion Bird.
Mario needs to attack the Fire Vellumental with the Iron Boots when it is alight with flames. When it takes damage, its feathers fall onto the arena and stick in the floor, which cause Mario 8-9 points of damage if he walks past. The Fire Vellumental can attack with Fireball causing around 20-21 damage, and use Molten Feathers to scatter more of its feathers around the arena. It can also use Flamecrower to repeatedly attack Mario for 8-10 damage. Similar to Rubber Band's bands flinging on the arena, the Fire Vellumental's HP is tied to the amount of feathers it has. When the arena becomes cluttered with feathers, the player needs to use the Water Vellumental Magic Circles to extinguish its flames, and make all the spaces safe to travel along. The Fire Vellumental can reignite itself and relight the flames in the arena after a couple of turns.
When the Fire Vellumental's flames are extinguished, it uses Mild Wings to deal around 15 damage. If the 1,000 Fold Arms are used on the Fire Vellumental when it is on fire it takes zero damage. However, if the attack is used when its flames are extinguished but with its HP bar above 25%, the Fire Vellumental takes minimal damage and then will regain all its HP, using Hot Wings to recoup all its lost feathers. However, the 1,000 Fold Arms are needed to finish off the boss when it gets down to 25% HP, as the arms are needed to pluck out its head feathers.
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