With this spell, the caster causes a blazing ray of red-hot fire to spring forth from his hand. This bladelike ray is wielded as if it were a scimitar. If the caster successfully hits with the flame blade in melee combat, the creature struck suffers 1d4+4 points of damage, with a damage bonus of +2 (i. e., 7-10 points) if the creature is undead or is especially vulnerable to fire. If the creature is protected from fire, the damage inflicted is reduced by 2 (i.e., 1d4+2 points). Fire dwellers and those using fire as an innate attack form suffer no damage from the spell. The flame blade can ignite combustible materials such as parchment, straw, dry sticks, cloth, etc. However, it is not a magical weapon in the normal sense of the term, so creatures (other than undead) struck only by magical weapons are not harmed by it. This spell does not function under water.
In addition to the caster's holy symbol, the spell requires a leaf of sumac as a material component.