Expelliarmus was definitely Harry's, but what spells did other wizarding world characters favour?

Ginny and the Bat Bogey Hex

Ginny Weasley’s aptitude for the Bat Bogey Hex was impressive enough to earn her the admiration of no less a talent-spotter than Professor Slughorn. As the youngest Weasley, we’re sure Ginny observed more than her fair share of unpleasant spells over the years but it was the Bat Bogey Hex she was famous for – and with good reason. This was the spell that overpowered Draco Malfoy and the Inquisitorial Squad, and also secured her an invite to the Slug Club. Now, Ginny might not have been bothered about the Slug Club, but her ability to execute a Bat Bogey attack shows just how much nerve she really had, and on this point we’re in full agreement with Slughorn…

You want to be careful, Blaise! I saw this young lady perform the most marvellous Bat Bogey Hex as I was passing her carriage! I wouldn’t cross her!
Professor Horace Slughorn
Harry Potter and the Half Blood Prince

Underestimate Ginny at your peril.

Professor Lockhart and his Memory Charms

The incantation for a Memory Charm was Obliviate, which seems quite fitting for Professor Gilderoy Lockhart, given how (seemingly) oblivious he was to his own shortcomings. Vain, selfish, and as full of himself as he was, Lockhart did have a real talent for making other people forget their achievements so that he could take credit for them, without fear of repercussion. Basically, he loved a Memory Charm because he was a big liar. It’s not much to write home about, is it? All in all, we can’t think of a better consequence for such breathtaking arrogance than being hit by your own backfiring Memory Charm. Obliviate, indeed.

Hermione’s bluebell flames

Hermione’s magical talents meant she was good at every spell, right from the beginning – Wingardium Leviosa, anyone? But the bluebell flames she once used against Snape became one of her trademarks, and it’s also one of our favourites. Hermione used it to help her, Ron and Harry escape the Devil’s Snare in Philosopher’s Stone and, later, to keep them warm during the Horcrux hunt. It was a practical spell that always came in useful, giving out light and warmth when it was most needed. Just like Hermione herself.

Ron and the ‘eat slugs’ spell

It’s not exactly Ron’s signature spell, but we will forever remember the way his ‘eat slugs’ curse backfired in Chamber of Secrets, leaving him to vomit slimy creatures all over Hagrid’s hut. Perhaps this is because it was so very Ron: a bit silly, pretty funny, and the kind of spell to cast in anger, without a thought for the consequences. That, and it happened when Ron was attempting to curse Malfoy in defence of Hermione, which is also kind of sweet. You know, in a grotesque way.

Voldemort and Avada Kedavra

It is no surprise that Voldemort liked casting Unforgivable Curses – he’d use anything to stop those who stood in his way. The ever-loyal Bellatrix Lestrange once explained to Harry the art of the Unforgivable Curse:

You need to mean them, Potter! You need to really want to cause pain – to enjoy it – righteous anger won’t hurt me for long – I’ll show you how it is done, shall I?
Bellatrix Lestrange
Harry Potter and the Order of the Phoenix

Like her master Bellatrix did clearly enjoy causing pain, but where she had a particular talent for the Cruciatus Curse, Voldemort tended to favour the simple act of killing. Avada Kedavra was undoubtedly his signature spell. As when he used it on Cedric Diggory, it was quick, clean, and without mercy. Expect, of course, when it came to Harry…

Harry and the Patronus charm

We’re not going to deny that Expelliarmus was Harry’s signature spell. Lupin said so, after all, and given it was the spell Harry used to ultimately defeat Voldemort, he was not wrong. But Harry also had a proven talent for that oh-so difficult spell Lupin himself taught him. Casting a Patronus was very advanced magic, but by his fifth year Harry was so adept at it that he was able to save his cousin Dudley’s life, impress the Head of the Department of Magical Law Enforcement, and begin teaching his fellow students how to cast it when they formed the DA. Which is – as Madam Bones, the said Head of the Department of Magical Law Enforcement, proclaimed – very impressive indeed.