Fiendfyre

Fiendfyre
Incantation	Pestis Incendium (PESS-tis in-SEN-dee-um)
Type	Curse
Hand movement
Light	Fire
Effect	Unleashed cursed fire

"It was not normal fire; Crabbe had used a curse of which Harry had no knowledge: as they turned a corner the flames chased them as though they were alive, sentient, intent upon killing them. Now the fire was mutating, forming a gigantic pack of fiery beasts: Flaming serpents, Chimaeras, and dragons rose and fell and rose again, and the detritus of centuries on which they were feeding was thrown up in the air into their fanged mouths, tossed high on clawed feet, before being consumed by the inferno."

— Description

Fiendfyre, or the Fiendfyre Curse (Pestis Incendium), was a deadly curse that produced powerful enchanted flames of immense size and heat that were capable of destroying nearly anything and everything in its path, taking the form of gigantic fiery magical beasts such as serpents, chimaeras, and dragons that sought out living targets. The extremely volatile and sentient cursed fire spread rapidly, and incinerated nearly everything through mere physical contact. Fiendfyre required extreme skill and intense concentration to control.

This curse was an advanced type of Dark Magic, and it was one of the few known substances capable of destroying Horcruxes. The curse was also similar, but different to the protective dark charm Protego Diabolica.

Description and effects

"Fiendfyre — cursed fire — it's one of the substances that destroy Horcruxes, but I would never, ever have dared use it, it's so dangerous."

— Hermione Granger on the dangers of Fiendfyre

Fiendfyre conjured by Vincent Crabbe in the Room of Requirement during the Battle of Hogwarts

Fiendfyre was an immensely powerful type of enchanted fire, burning at severely high temperatures. It could not be extinguished by normal or conjured water. It was also very difficult for the caster to control, flowing from their wand in a continuous stream of flame. If the caster flicked their wand when the stream of flame was still running from it, a jet of fire would shoot off and take the form of a large beast made of flame that almost seemed to have a mind of its own.

When cast, the fire appeared with a roaring, billowing noise which gave its victims only a split-second's warning to escape, quickly consuming anything in the vicinity of its caster; it was difficult for the caster to control the movement of the abnormally large flames. The flames could take the form of fiery serpents, dragons, and Chimaeras, constantly mutating into other beasts as well as powerful, formless flames that spread rapidly, and were able to destroy all things around itself at the caster’s wishes. The fire even possessed a sentience of its own, a continuous (though far from latent) desire to burn anything it could. It pursued and incinerated any nearby lifeforms and physical forces through mere physical contact, and was even able to kill its own caster if it had the chance.

Fiendfyre required exceptional skill and full concentration in order to control it. There was also a counter-curse to cease the flames, but unfortunately Vincent Crabbe never paid enough attention in class to learn it, therefore costing him his own life at the hands of the fire he conjured himself. Casters with greater skill and experience had an easier time controlling the flames, and could even direct them to attack their opponents. It is unknown if the fire was able to burn off on its own since it could not be extinguished by external forces. It also could not be put out with normal or enchanted water. In fact, the only known thing capable of ceasing the Fiendfyre curse was its aforementioned counter-curse, which was very difficult to perform.

Fiendfyre was one of the few substances known with the ability to destroy a Horcrux. During a skirmish in the Room of Requirement during the Battle of Hogwarts, Vincent Crabbe's Fiendfyre destroyed Rowena Ravenclaw's diadem, which was the fifth of Voldemort's Horcruxes.

Known uses

Caster(s)	Date	Notes
Merula Snyde	1988–1989 school year	"Fiendfyre can't be extinguished with ordinary water. Even your 'misfire' would be far too powerful. [...] Let's start with even attempting to cast a bewitched flame in my very flammable classroom. It's fortunate I stopped by to see how your lesson is going." — Patricia Rakepick to Merula Snyde and Jacob's sibling Merula tried to teach Jacob's sibling this curse in Classroom 3C, however she lost the control of the fire until Professor Patricia Rakepick came and immediately extinguished it.
Verucca Buckthorn-Snyde	22 June 1991	Verucca conjured Fiendfyre in anger at the Viaduct to attack Peregrine with cursed flames during the Battle on the Bridge. The flames made him fall off the Viaduct without his wand.
Amycus Carrow	1997–1998 school year	Harry Potter speculated that Amycus was the one to teach Vincent Crabbe how to summon Fiendfyre, since he was the Dark Arts professor at Hogwarts that school year.
Vincent Crabbe	2 May 1998	Crabbe cast it during a skirmish in the Room of Requirement, during the Battle of Hogwarts, while it was transformed into the Room of Hidden Things. He conjured it in an attempt to kill Harry Potter, Hermione Granger and Ron Weasley in the room. He died in the ensuing magical inferno, having been unable to extinguish the flames. His use of Fiendfyre also destroyed Ravenclaw's Diadem, which was one of Voldemort's Horcruxes.

Known practitioners

"Like it hot, scum?"

— Vincent Crabbe having summoned Fiendfyre in the Room of Requirement

Merula Snyde

Verucca Buckthorn-Snyde

Amycus Carrow (possibly)

Vincent Crabbe

Etymology

In Latin, pestis translates to "plague" or "pest". A plague is defined as "a contagious disease that spreads rapidly and kills many people". Incendium means "fire". Together, Pestis Incendium can be translated to "fire plague", which alludes to the Fiendfyre Curse's ability to spread rapidly and incinerate anything in its path if left uncontrolled and/or unchecked. The wording pest can also be interpreted to allude to the curse's ability to create dangerous, rapid-spreading fiery beasts and animals that incinerated anything upon physical contact. As for the name of the spell, Fiend means "enemy, demon, devil", while fyre comes from the Old English word "fyr" and means simply fire. Together, it can be referred to as the "devil's fire" or "hellfire."

Behind the scenes

Goyle dies in his own Fiendfyre in Harry Potter and the Deathly Hallows: Part 2

• In Harry Potter and the Deathly Hallows: Part 2, Gregory Goyle conjures Fiendfyre and dies instead of Crabbe, since Jamie Waylett (who played Vincent Crabbe) had been cut from the film. Also, whereas Crabbe died because he could not run fast enough from the fire, Goyle was depicted as having been unable to stop the flame from pouring out of his wand (who then ends up throwing it into the flames), and falling into the flames from grabbing a loose chair while climbing up a mountain of various objects to safety.
  • Additionally, water could be used to douse the fire, though the rate the flames spread limited its effectiveness.
  • Additionally, Fiendfyre was not used to completely destroy Rowena Ravenclaw's Diadem. Instead, Harry stabbed it with the Serpent of Slytherin's fang to fatally damage it first, and then Ron kicked it into the Fiendfyre to finish the job. This led Voldemort's mangled soul to possess the flames briefly and scream in pain before it was destroyed.
• In the film adaptation of Harry Potter and the Goblet of Fire, the spell used by Durmstrang students at the beginning of the Triwizard Tournament for show bears resemblance to Fiendfyre, though as the film came out before the curse debuted in the books, it's likely that the similarity was coincidental.
• In the film adaptation of Harry Potter and the Order of the Phoenix, Lord Voldemort conjures a giant fire snake during his duel with Albus Dumbledore, who manages to hold off the flames.
• In the film adaptation of Harry Potter and the Half-Blood Prince, Bellatrix Lestrange may have used Fiendfyre to destroy The Burrow.
• Fiendfyre is similar to Protego Diabolica (as seen in Fantastic Beasts: The Crimes of Grindelwald), which creates a protective ring of black fire around the caster which incinerates enemies of the caster and leaves their allies unharmed. The flames can also be unleashed to destroy a large area, although the General Counter-Spell can extinguish it.
• It is possible that Gormlaith Gaunt may have used this curse or similar spell to burn down her sister's cottage in the 17th century as she was able to easily rescue her niece without being harmed.

Appearances

• Harry Potter and the Goblet of Fire (film) (Possible appearance)
• Harry Potter and the Order of the Phoenix (film) (Non-canonical appearance)
• Harry Potter and the Half-Blood Prince (film) (Non-canonical appearance)
• Harry Potter and the Deathly Hallows (First appearance)
• Harry Potter and the Deathly Hallows: Part 1 (Possible appearance) (Appears in flashback(s))
• Harry Potter and the Deathly Hallows: Part 2
• Harry Potter and the Deathly Hallows: Part 2 (video game)
• Pottermore
• Harry Potter (website) (Mentioned only)
• LEGO Harry Potter: Years 5-7
• Harry Potter for Kinect
• Harry Potter: Hogwarts Mystery
• Harry Potter: Wizards Unite (Mentioned only)
• Harry Potter: Magic Awakened
• Harry Potter: Magic Caster Wand (First identified as Pestis Incendium)

See also

• Firestorm
• Protego Diabolica