Boggart

"So the boggart sitting in the darkness within has not yet assumed a form. He does not yet know what will frighten the person on the other side of the door. Nobody knows what a boggart looks like when he is alone, but when I let him out, he will immediately become whatever each of us most fears."

- Professor Lupin to his third year class in 1993

A Boggart is an amortal shape-shifting non-being that takes on the form of the viewer's worst fear. Because of their shape-shifting ability, no one knows what a Boggart looks like when it is alone, as it instantly changes into one's worst fears when one first sees it.

When facing a Boggart, it is best to have someone else along, to try to confuse it, since facing more than one person at once would make it indecisive as to what form it must take, usually a mixed-up amalgam of the victims' fears.

Boggarts would, at least before the Battle of Hogwarts, very commonly appear as Lord Voldemort since he represented the worst fear of many wizardkind.

Physical appearance
Nobody knows what a Boggart looks like if nobody is there to see it, although it continues to exist, usually giving evidence of its presence by rattling, shaking or scratching the object in which it is hiding. Boggarts particularly like confined spaces, but may also be found lurking in woods and around shadowy corners.

Nature
"A Boggart is a shape-shifting creature that will assume the form of whatever most frightens the person who encounters it."

- A boggart's basic nature

Much like Poltergeists, Boggart are non-beings, who, although they resemble living creatures, are not considered magically "alive" and are as a result amortal (a Boggart can be made to disappear, but it will inevitably reappear, with several more by its side at times). Much like Poltergeists with mischief and Dementors with gloom and depression, Boggarts seem to embody the human emotion of fear, and consequently feed on other beings' fears.

Boggarts' ability to shapeshift shows remarkable speed and fluidity, but has several limitations. Firstly, being confined, if nothing else, by the size of the room it inhabits, the Boggart will scale down an otherwise-gigantic form (as seen when a Boggart turned into the Moon). Secondly, though a Boggart who transforms into a magical being or object can replicate its abilities to an extent, this will be a weaker facsimile of the real thing; thus, a Boggart transformed into a Dementor has weaker magic than a real Dementor (according to Professor Lupin, who exploited this effect to simulate a Dementor attack in Harry's presence to help him perfect the use of the Patronus Charm at no serious risk to Harry Potter's soul.)

Additionally, when a witch or wizard has multiple fears that tie for their "worst," the Boggart will typically cycle through those fears, presumably randomly. For example, in 1995, when Molly Weasley was attempting to destroy a boggart that had taken up residence in 12 Grimmauld Place, the Boggart took the form of the freshly dead bodies of her family, as well as Harry Potter, whom she loved like a son. Since she feared the deaths of all her loved ones equally, the Boggart cycled through all the corpses randomly.

The extent of Boggarts' intelligence is unclear; though they sometimes take the forms of sentient beings as part of their fear-inducing transformations, those false "people" appear to be little more than caricatures, acting out the motions of the victim's fear involving said people, heedless of their surroundings. It is worth noting however that one Boggart once settled into the form of a human killer, foregoing individual transformations, and successfully posed as this man for a long period of time; and Boggarts' closest-known "relatives", Poltergeists and Dementors, both possess sapience.

Though they cannot see other non-beings like Dementors, Muggles can sometimes see Boggarts; however, as most Muggles refuse to acknowledge anything that might even be considered somewhat magical, the glimpses they catch of Boggarts are usually dismissed as mere hallucinations or figments of the viewer's imagination. This denial is helped by the fact that Muggles rarely see Boggarts plainly, due to their favoured haunts being dark places away from the public eye.

Defence against a boggart
The charm that combats a Boggart is Riddikulus. The charm requires a strong mind and good concentration. The incantation and wand movement alone will not affect a Boggart. The spell can be tricky, because it involves making the creature into a figure of fun, so that fear can be dispelled in amusement. If the caster is able to laugh aloud at the Boggart, it will disappear at once. The intention is to force the Boggart to assume a less-threatening and hopefully comical form.

In 1993, this charm was taught by Remus Lupin during a third year Defence Against the Dark Arts lesson at Hogwarts School of Witchcraft and Wizardry.

Having multiple people facing one Boggart may reduce its effectiveness of frightening its victims, since it would not be able to determine which form to take.

Hiding places
Boggarts are particularly fond of inhabiting dark, confined spaces, such as in wardrobes, the gap beneath beds, and the cupboards under sinks and desks. On at least one occasion, a boggart was found hiding in a grandfather clock. They also like shadowy corners.

Famous Boggarts
Famous Boggarts include the Old Boggle of Canterbury (believed by local Muggles to be a mad, cannibalistic hermit that lived in a cave; in reality a particularly small Boggart that had learnt how to make the most of echoes); the Bludgeoning Boggart of Old London Town (a Boggart that had taken on the form of a murderous thug that prowled the back streets of 19th century London, but which could be reduced to a hamster with one simple incantation); and the Screaming Bogey of Strathtully (a Scottish Boggart that had fed on the fears of local Muggles to the point that it had become an elephantine black shadow with glowing white eyes, but which Lyall Lupin of the Ministry of Magic eventually trapped in a matchbox).

1986–1987 school year
During that school year, the Vault of Fear was tampered with, which caused a large number of Boggarts to appear in an unusually high frequency around the school. One incident involved a Boggart appearing in a greenhouse during a Herbology class, scaring Penny Haywood. After Jacob's sibling and friends opened the vault and defeated the Boggarts guarding it, the curse was broken and Boggarts stopped appearing so often.

1993–1994 school year
"That suggests that what you fear most of all is — fear. Very wise, Harry."

- Remus Lupin regarding what Harry Potter fears

In 1993, Professor Remus Lupin taught his third year Defence Against the Dark Arts students about how to defend against Boggarts. He took the class to the staffroom, where a Boggart had moved into a wardrobe the previous afternoon. After explaining what they would need to do, Professor Lupin let the class, starting with Neville Longbottom, perform the Riddikulus charm on the Boggart. When the Boggart moved towards Harry Potter, Lupin drew the Boggart's attention, causing it to turn into a full moon, then had Neville finish it off.

Later, Professor Lupin explained that the reason he didn't let Harry face the Boggart was that he thought Harry's boggart would turn into Lord Voldemort, and he didn't want to panic the students. Harry's boggart actually took on the form of a Dementor, as he had an encounter with them on the way to Hogwarts that year and heard his mother's dying moments whenever they came near.

To help Harry, Professor Lupin taught him how to perform the Patronus, using a boggart found in Argus Filch's filing cabinet as a substitute for a real Dementor. In between the private lessons, Professor Lupin kept the Boggart in a cabinet under the desk, in his office.

At the end of the school year, Lupin used another boggart as part of his third year exams, as the final obstacle in a series.

1994–1995 school year
On 24 June, 1994, Harry Potter came across a Boggart in the Triwizard Maze during the Third Task of the Triwizard Tournament of that year. Harry initially thought the Boggart was actually a Dementor, thus casting his Patronus, and realised that the creature was in fact a Boggart when it fell back and tripped over the hem of its robes instead of being driven back, as a real Dementor would have done.

Number 12 Grimmauld Place
While cleaning up 12 Grimmauld Place, the new headquarters of the reconvened Order of the Phoenix, Molly Weasley stumbled across what she thought was a Boggart in a locked cabinet of a writing desk. She decided to wait for Alastor Moody to confirm it was a Boggart, before opening the cabinet.

After escaping from the party being held in celebration of Ron Weasley and Hermione Granger becoming Prefects, Harry heard sobbing coming from the drawing room. When he looked inside, Harry saw Mrs Weasley cowering against a dark wall, and the body of her son, Ron, sprawled on the floor. After Molly tried the Riddikulus charm without success, Ron's body turned into the body of Bill Weasley, with his eyes wide open and empty. Molly's next attempt turned Bill's body into Arthur Weasley, with blood running down his face. The next attempts turned the boggart into Fred and George Weasley, Percy Weasley, and then Harry.

Harry shouted to Mrs Weasley that she should leave, causing Remus Lupin and Sirius Black to run into the room, followed by Alastor Moody. Lupin quickly figured out what had happened, and made the Boggart turn from Harry's dead body to the full moon, then with a wave of his wand, made the orb vanish in a puff of smoke.

Unspecified
Although the precise details of this encounter are unknown, Lupin mentioned during his first lesson that he had once had an encounter with a Boggart in the company of at least two other people where the Boggart, attempting to frighten two people at once, turned itself into half a slug (One person was afraid of a flesh-eating slug and the other was afraid of headless corpses).

Known Boggart forms
"P-P-Professor McGonagall! Sh-she said I'd failed everything!"

- Hermione Granger faces her Boggart

The following individuals all have Voldemort as their Boggart form, and after performing the Boggart-Banishing Spell, Lord Voldemort would suck a dummy:

Etymology
In Celtic mythology, a boggart (or bogart, bogan, bogle or boggle) is a household spirit, sometimes mischievous, sometimes helpful.

Behind the scenes

 * 'Boggart' is David Thewlis' (actor of Remus Lupin in the series) favourite word/line from the series.
 * In mythology, the Boggart actually lives in marshes or fields and has a short, grotesque, hairy appearance. The Boggarts in Harry Potter are more similar to the Bogeyman, being found in closets, under furniture, and cupboards and able to transform into one's worst fear.
 * It is unknown if Boggarts can change into intangible fears like darkness, certain sounds or mental/physical illnesses. It is also unknown how they adapt to people who are only afraid of interacting with non-sentient concepts like drowning, loneliness or claustrophobia. Unless the Boggart is somehow able to engulf a person with these or similar fears it is likely they are powerless against them and might even be exposed in their actual form to these people.
 * It is possible that the Boggart knows ways to symbolise these fears; for example, in the case of a person with Hydrophobia, showing the viewer their drowned corpse. This is supported in canon by Lord Voldemort (who feared death) seeing his own corpse, Remus Lupin (who feared his werewolf transformation) seeing the full moon, and Hermione (who feared failure) seeing Professor McGonagall telling her that she failed all of her exams. Mrs Weasley feared her loved ones dying, so the Boggart showed her loved one's corpses in succession, which supports this theory even further.
 * In, Remus Lupin mentions that no one knows what a Boggart looks like when it is alone. Alastor Moody, in , is able to determine through his "mad" eye that a creature hiding in 12 Grimmauld Place is definitely a Boggart. It is assumed that Moody knew what a Boggart looked like in its true form as the Boggart had not seen him and shape-shifted.
 * J. K. Rowling has stated that her Boggart would be the same as Molly Weasley's: her loved ones dead or alternatively herself buried alive. In an earlier interview, however, before the publication of, she suggested Aragog as a possible Boggart for her, as she hates spiders.
 * In, Remus Lupin gives Harry private lessons on how to defeat Dementors, using a Boggart as a replacement. However, when Harry faced the Boggart the first and second time, when he failed to beat it, the Boggart/Dementor had managed to make Harry hear his mother's screams. This may imply that Boggarts can gain some abilities of the thing it morphs into. It also gained its weakness as it was easily defeated by Harry's Patronus.
 * Lupin's Boggart, the full moon, indicated his dread of his transformations into a werewolf. However, the Boggart failed to frighten him because it is not the moon itself he feared, but its effect on him.
 * The Boggart may have been inspired by the "Clutterbumph" from Manxmouse, of which Harry Potter series author J.K. Rowling is a known fan. The Clutterbumph is described as follows: "...something that is not there until one imagines it. And as it is always someone different who will be doing the imagining, no two Clutterbumphs are ever exactly alike. Whatever it is that frightens one the most and that is just about the worst thing one can think of, that is what a Clutterbumph looks like."
 * The Boggart also bears a resemblance to the, a monster in Hispanic and Latino folklore. Like the Cucuy, the Boggart lives in dark areas such as beneath beds and inside closets, and has the ability to change its shape at will.
 * In, Molly Weasley's Boggart is shown to change from Arthur and other family members before going to Harry.
 * In an early script for, there were several differences from the final cut of the film. The Boggarts for Neville, Ron, Harry, and Professor Lupin remained the same. Parvati's, however, would have been a vampire (specifically Count Dracula ) which would have been dressed like (presumably referring to her famous fruit hat outfit from the film ) when the Boggart-Banishing Charm was used on it, with Dean having the cobra boggart Parvati has in the actual film.
 * Boggarts have been compared to the from the  novel , an ancient evil entity that took on the appearance of its targets' worst fears, most commonly appearing as Pennywise the Dancing Clown.
 * It could be possible that if someone who has no fear attempts to engage a Boggart, it will not be able to decide what to turn into and will be forced to show its true form
 * In, Jacob's brother Boggart of Voldemort after casting the Boggart-Banishing Spell, the clown Voldemort will dance in the same iconic style of Pennywise from the 2017 supernatural horror film .
 * Harry Potter and Neville Longbottom are the two known characters to have results for their respective Boggarts and outcomes featured in the film adaptation, the LEGO game, and the GBA game, and all true to the depictions in the books with no altercations.
 * In the film and video game adaptations of the series, changes were made to the following individual's Boggart form and Boggart-Banishing Spell outcome:

Notes and references
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