There are many mighty forces in the Harry Potter universe. The Patronus Charm, for example, is one of the most powerful defensive charms out there. This spell, conjured by evoking happy thoughts while using the Expecto Patronum incantation, is used to conjure a Patronus or spirit guardian created of positive energy, which defends its conjurer from Dementors and Lethifolds.

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Since the Patronus Charm is a very strong charm, it's also one of the most difficult spells to learn, so many wizards and witches never learn how to do it. However, most members of Dumbledore's Army managed to conjure a corporeal version of their Patronus thanks to Harry's masterclass in The Order of the Phoenix. This spell came very handily when Lord Voldemort released Azkaban's Dementors during the Battle of Hogwarts.

10 Neville Longbottom: A Non-Corporeal Patronus

Neville Longbottom in Harry Potter

One of Harry's closest friends outside the Golden Trio, Neville is a clumsy and socially anxious student who started his Hogwarts education at the same time that the main characters. In the beginning, Neville wasn't the brightest Hogwarts student. However, as he grew up, it became obvious he was brave, determined, and, especially, loyal.

Like Lavender Brown, Parvati and Padma Patil, and many other Hogwarts students who joined Dumbledore's Army, Neville doesn't have a corporeal Patronus. Instead, he only manages to produce a wisp of silver that doesn't offer as much protection. Since the Patronus is a complicated charm, this isn't an uncommon occurrence.

9 Ernie MacMillan: A Boar

ernie macmillan teasing harry potter in the goblet of fire

Ernest "Ernie" MacMillan is a Hufflepuff student who went to Hogwarts at the same time as Harry, Ron, and Hermione. He's a pompous but intellectual student who is always around Hannah Abbott and Justin Finch-Fletchley. Although he wasn't close to Harry  and even bullied him when he competed against Cedric Diggory in the Triwizard Tournament  he fought bravely alongside other members of the Dumbledore's Army in the Battle of Hogwarts.

A proficient student with great abilities for charms, Ernie managed to produce a Patronus during the Battle of Hogwarts, which took the shape of a boar. According to the Wizarding World website, this is very telling of Ernie's stubbornness because it shows he's pig-headed.

8 Seamus Finnigan: A Fox

Devon Murray as Seamus Finnigan in Harry Potter.

A recurrent Gryffindor student in the saga, Seamus Finnigan is a half-blood Irish wizard who shared the boys' dormitory with Harry, Ron, Neville, and his best friend, Dean Thomas. While his friendship with Harry was always only circumstantial, Seamus joined Dumbledore's Army because he believed in their cause.

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Although he wasn't particularly known for his magical talent, Seamus managed to produce a corporeal Patronus in the shape of "something hairy" for a couple of seconds during a Dumbledore's Army meeting. Two years later, during the Battle of Hogwarts, he conjured again for a longer time, now in the concrete shape of a fox

7 Cho Chang: A Swan

Katie Leung as Cho Chang from Harry Potter

Cho Chang is one of Ravenclaw's most popular students. She's a smart and beautiful girl with whom Harry had a crush during his fourth year at Hogwarts. Although she was also interested in him, their relationship didn't last much because Cho sided with her best friend, Marietta Edgecombe, after she blew the whistle on Dumbledore's Army.

During training with Dumbledore's Army, Cho did poorly sometimes, especially when it came to spells. However, she also showed her talent many times, like when she was able to conjure her swan-shaped corporeal Patronus.

6 Fred & George Weasley: A Magpie

Fred and George Weasley sitting together in the Gryffindor Common Room

To their mother's chagrin, Fred and George Weasley are two smart, fun-loving, and witty young men whose main goal in life is to open a joke shop. Although they "pull a Weasley," leaving Hogwarts amidst a chaos of their own creation, they're close to the Golden Trio up until the end.

Both Fred and George are able to conjure a Patronus Charm in the shape of a magpie. Since every Patronus is unique, it isn't common for twins to share its shape as the Weasly twins do. The fact that Fred and George cast the same Patronus is a testament to their fraternal connection.

5 Ginny Weasley: A Horse

Ginny Weasley practicing with Dumbledore's Army

Since she's the youngest of the Weasley clan and Molly and Arthur's only daughter, Ginny had to learn to stand her ground since she was a little girl. She grew up to be an independent and capable woman and a talented witch, especially known for her curses.

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The books never describe Ginny's Patronus. However, in The Order of the Phoenix, she produces a silver horse during the Dumbledore's Army class centered on this charm. According to fan theories, this connects her to Harry because when The Boy who Lived first saw his own Patronus in The Prisoner of Azkaban, he thought it was a horse.

4 Luna Lovegood: A Hare

Luna reads an upside-down Quibbler

When Luna Lovegood first appeared in the Harry Potter saga during The Order of the Phoenix, she was ostracized by the Hogwarts student community and often bullied for her eccentric personality. However, it didn't take long for Harry and his friends to realize Luna was a skilled witch and a trustworthy ally.

Luna's Patronus is a hare. In fact, she wears a bracelet with this animal in honor of it. She uses this charm successfully twice throughout the whole saga. First, during a Dumbledore's Army meeting when she was only fourteen. Then, during the Battle of Hogwarts, to save Harry from Voldemort's dementors.

3 Hermione Granger: An Otter

Hermione sits with a book in Harry Potter and the Goblet of Fire

Hermione Granger, the only girl in the Golden Trio, is a muggle-born witch who accompanies Harry and Ron in all their adventures. Dubbed the brightest witch of her age, Hermione is an intelligent and resourceful woman. She's one of the founding members of Dumbledore's Army.

Even though she's especially known for her brilliant mind, Hermione struggled to conjure a corporeal Patronus the first time she attempted this charm. According to J.K. Rowling, Hermione's Patronus is an otter because this is the author's favorite animal.

2 Ron Weasley: A Jack Russell Terrier

Ron Weasley laughing at a joke in in Harry Potter

Ron Weasley is the youngest boy of the Weasley clan. He's an insecure but caring young man who often struggles with his family's socioeconomic status. Ron is Harry's first and best friend in the magical world. In a way, he's Harry's strongest connection to the magical world during his first years.

Ron's Patronus is a small dog, like a Jack Russell Terrier. According to J.K. Rowling, this is purely for sentimental reasons because she has one of these dogs at home. However, fans have noted that this breed is particularly known for chasing otters like Hermione's Patronus. Since Ron is Hermione's love interest by the end of the saga, this foreshadows their love.

1 Harry Potter: A Stag

Harry Potter Order of the Phoenix

An orphan since he was a baby, Harry Potter lived his whole life believing his parents had died in a car accident. When he was 11 years old, he found out this couldn't be further from the truth. After learning he was a wizard, Harry joined the Wizarding World, where he became a wizard by defeating Lord Voldemort half a dozen times.

As seen in The Prisoner of Azkaban, Harry's Patronus is a stag in honor of James Potter, his father, who was an unregistered animagus. Since James died when Harry was a baby, Harry never got a chance to be with him. However, his father accompanies him wherever Harry is. His Patronus is a testament to this love.

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