Well, there's 'Harry's Juvie Revelation'. In the beginning, it seems like a typical story of Harry in juvie, but then it takes a sharp turn when it's revealed that Harry's time in juvie was all part of a prophecy. He was meant to be there to learn certain life lessons that would make him a stronger wizard. This twist completely changes the perspective of the whole story and makes it a very interesting read.
In one fanfiction, the wands of all the Death Eaters are secretly being controlled by an ancient and forgotten magical entity. This entity is using the Death Eaters to gather power and the main characters have to figure out this connection between the weapons (the wands) and the entity to stop it. It's a plot twist that completely changes the power dynamics in the wizarding world as we know it from the original books.
There is a fanfiction where it is revealed that Professor McGonagall was given a prophecy about Harry Potter long before Dumbledore knew. This prophecy was not just about his fight against Voldemort but also about his role in uniting different wizarding factions. As the story unfolds, McGonagall has to guide Harry in fulfilling this greater destiny, which is a huge plot twist from the original story's focus mainly on Voldemort.
A popular one is 'Harry Potter: Juvie Years'. It shows Harry's life in juvie and how his magical abilities start to manifest in strange ways. For example, he accidentally makes the lights flicker when he's angry. The story also has a sub - plot about a mysterious figure who seems to be watching Harry from the shadows, and it keeps you guessing as to who it might be and what their intentions are.
A really interesting 'Harry Potter' funny fanfic with plot twists is the one where the time - turner Hermione used actually sends her and Harry back to the time of the Founders of Hogwarts. The humor comes in as they try to fit in and use their modern - day magic in a very different era. There are plot twists like when they accidentally change the house colors and the sorting system. Also, they end up befriending a young Slytherin who is nothing like the Slytherins they know, and this young Slytherin helps them get back to their own time in a very unexpected way.
Yes. There's a fanfiction where the rifle is actually a cursed object that was once used by a dark wizard. But when Harry touches it, it turns into a powerful weapon against the dark forces. It has a plot twist where the rifle seems to be leading Harry astray at first, but in the end, it's the key to victory.
Yes, in some fanfictions, a common plot twist is that the slave actually has a hidden power that can break the contract. For example, they might discover they are part of an ancient bloodline with special magic that can nullify the enslaving contract.
There's a fanfic titled 'Percy's Hidden Power'. The plot twist here is that Percy has a hidden power that no one knew about, not even himself. As he starts to uncover this power, it leads to a series of events that put him in a different light in the eyes of Harry and the rest of the wizarding community. Also, 'Percy's Unlikely Alliance' has a cool twist. Percy ends up allying with one of Voldemort's former followers who has a change of heart, and together they work towards a common goal with Harry and his friends, which is completely unexpected.
A fanfiction that has a unique plot twist is one where Ron and Hermione accidentally switch bodies. This leads to all sorts of comical and also deep - thinking situations as they have to understand each other's perspectives in a very literal way. They also have to keep it a secret from Harry and the others at Hogwarts.
One unique 'Harry Potter guitar fanfiction' could be that the guitar was a gift from Dumbledore to Ginny. But it turns out that the guitar has the ability to open a portal to a time - locked dimension where the founders of Hogwarts are still alive. Ginny, with her love for music and adventure, enters the portal and has to convince the founders to help Hogwarts in its current crisis. The guitar is the key to getting back as well as the means to communicate with the founders.
In a particular fanfiction, the disease seems to target only pure - blood wizards. This causes a huge uproar in the wizarding community as they suspect it's a plot by Muggle - borns. But later it's revealed that the real cause is a magical artifact that was activated by accident. The plot twist lies in the fact that the solution is not about blood purity but about restoring the balance of an ancient magic that the artifact disrupted. It's a great exploration of the themes of prejudice and unity in the HP world.