Everyone crack open your volume of "Secrets of the Darkest Art." Grab your copies of "Magick Moste Evile." It's time to talk Horcruxes.
In the world of "Harry Potter," there is perhaps no act of magic more terrible than the act of creating a Horcrux. The topic has been banned from most books on the dark arts, the spell so unforgivable it somehow falls on the other side of the three Unforgivable Curses.
This is because, to create a Horcrux, one most split their soul through the ultimate act of violence: murder. In doing so, they can leave part of their soul for safe (or not) keeping in a vessel separate from their body. The Dark Lord — aka Voldemort — created seven Horcruxes in an attempt to sustain immortality.
But, as you may have heard, Voldemort's plan ultimately failed. Harry Potter and co. found and destroyed all of his Horcruxes. This is the definitive ranking of Voldemort's Horcruxes, from least to most effective.
Rowena Ravenclaw's diadem.
Points for no one knowing what the word "diadem" meant — this made finding and destroying Rowena's pretty hair accessory a bit harder. But, all in all, not a very effective Horcrux. Shiny, tho!
Helga Hufflepuff's cup.
There's something particularly upsetting about turning a badger-engraved Hufflepuff item into an instrument for the dark arts. Perhaps fittingly, the Hufflepuff cup Horcrux didn't pose too much trouble for Harry, Ron, and Hermione. Once they figured out Bellatrix Lestrange had something important hidden inside of her Gringotts vault, it was easy peasy. OK, there may have been some Polyjuice Potion and dragon-riding involved, but that was more Gringotts' security measures' fault than the Horcrux's.
Salazar Slytherin's locket.Warner Bros.
Talk about a problem Horcrux! Voldemort went to great efforts to keep this particular Horcrux out of his enemies' hands, hiding it in a seaside cave infested with Inferi and protected by a potion that would make its drinker relive their worst moments, fears, and regrets. Harsh, Voldy.
Ultimately, the Slytherin locket's true effectiveness came in the way it influenced its wearer, as thoroughly explored in Harry, Hermione, and Ron's wearing of it during their larger search for Horcruxes. It eventually led Ron to abandon his friends for a brief time, because he was so overcome with jealousy and anger. Tellingly enough, it didn't seem to affect Umbridge's personality in the slightest.
Tom Riddle's diary.
The first of Voldemort's Horcruxes, Tom Riddle created this Horcrux when he was still a student at Hogwarts. Perhaps because it was the Horcrux created while Voldemort still maintained some of his humanity, its grasp on humanity is its greatest strength. What 11-year-old isn't looking for a friend to confide in? Someone who understands the unique loneliness of existing when it feels like no IRL person does? Tom Riddle's diary was so effective because it started with friendship and worked its way up to control, drawing Ginny Weasley into its game. Also, it almost killed Harry. And it's waterproof. ☔
Harry Potter.Warner Bros.
Harry's effectiveness as a Horcrux is the ultimate paradox. On the one hand, he brought about Voldemort's ultimate destruction, making him the least effective Horcrux of ALL TIME. On the other hand, his very existence as the savior of the wizarding community — and, you know, a person — made him that much harder to sacrifice. Add in the fact that Voldemort wasn't even aware that Harry carried part of his soul made him and you have a thoroughly complicated and unpredictable Horcrux.
Harry ultimately chose to sacrifice himself, not realizing that he would be given another chance to live. He made the ultimate sacrifice for his friends and family, but Voldemort could have easily accidentally created a Horcrux in a wizard less prone to self-sacrifice. A less selfless wizard would have made a good Horcrux. Harry Potter, less so. But, still, The Boy Who Lived is not a terrible spot to keep part of your soul.
Marvolo Gaunt's ring.Warner Bros.
The ring that would lead to the great Albus Dumbledore's death. Sure, Dumbledore was technically killed by Snape, at Dumbledore himself's request, so as to keep Draco from carrying out the dark deed. However, it's hard to imagine that this decision would have been as easy to carry out if Dumblefore hadn't already been dying from the effects of the Gaunt ring — a fact both Dumbledore and Snape knew.
The ring gets further points for having the frakking resurrection stone — one of the three Deathly Hallows — as its centerpiece, but loses effectiveness point for the fact that Tom Riddle wore it while at Hogwarts. This made deducing that it was, in fact, one of Voldemort's Horcruxes much easier for his enemies. #SuperVillainFail
Let's be real: Nagini was a badass. As Voldemort's right-hand snake, she was ever ready to do her master's dirty work — whether it be killing poor, defenseless Muggle grounds-keepers or helping to bring a body-less Voldemort back to life. She was also pretty difficult to kill, probably because she was so gosh darn scary. It took a creature as equally fearless, one Neville Longbottom, to take Nagini out. But you better believe Nagini went down fanging, making her the ultimate Horcrux. (Sorry, diadem!)