The Fiery Sword is a normal Sword, which has a Fire Aspect I Enchantment.
It does 6-8 Hitpoints Damage.
The Fiery sword is part of the tools and armor set made from Fiery ingots, which require Fiery blood and iron to craft, so they are expensive. They are added by the Twilight Forest mod, and you can occasionally find the sword in Loot chests in the Twilight Forest Dimension.
Crafting:
Fiery sword Crafting Recipe By: happyandfunny101 on youtube