Well, a typical plot device is the false evidence. The fanfiction could present Harry with false evidence that Dumbledore has been working for Voldemort all along. This makes Harry believe that he has to kill Dumbledore to save the wizarding world. Another device might be a broken bond of trust. If Dumbledore does something that breaks Harry's trust completely, like sacrificing Harry's friends for some greater good in a way Harry can't forgive, it could lead to the fateful act.
Often, a major plot device is a hidden secret about Dumbledore. Maybe there's a dark secret from his past that, when revealed, makes Harry see him as a threat. For instance, if Dumbledore was somehow involved in the death of Harry's parents in a way Harry discovers, it could lead to him killing Dumbledore. There could also be a situation where a powerful magical object corrupts Harry's judgment and causes him to turn on Dumbledore.
One common plot device is mind control. For example, Voldemort or some other dark force could control Harry's mind and make him kill Dumbledore without his full awareness. Another is a misinterpreted prophecy. Harry might think Dumbledore is endangering his life based on a wrongly understood prophecy.
The redemption arc of some Death Eaters can also be a plot device. In some fanfictions, Harry tries to save some of the Death Eaters who he believes can be redeemed. This adds a layer of complexity to the story as he has to balance his desire for revenge with his moral compass. He may end up sparing some Death Eaters who then help him in his fight against the more hardcore ones.
One popular plot device is the power - up. Naruto might gain a new form or a super - powerful jutsu right before facing an Akatsuki member. Another is the betrayal within the Akatsuki. For example, someone in the Akatsuki might give Naruto information to help him in the fight. And the 'damsel in distress' can also be used, like Naruto has to save a friend from an Akatsuki member, which leads to the fight and the kill.
A typical plot device could be a power - up related to their brotherhood. Since Naruto has his chakra and Trunks has his Saiyan strength, they might discover a new combined power because they are brothers. Also, there could be a time - travel element involved. Trunks is associated with time travel in Dragon Ball, and this could be used in the fanfiction to explain how Naruto and Trunks' relationship came to be. For instance, Trunks could travel to the Naruto universe and somehow become related to Naruto through some time - warped event.
One common plot device is the discovery of her royal lineage. It usually happens in a dramatic way, like finding a hidden letter or a magical object that reveals her true identity. Another is the conflict between her wizarding life and her new royal duties. She has to balance things like going to Hogwarts and attending royal functions. Also, there's often a love interest from the royal court, which creates a love triangle with her existing relationships in the wizarding world.
A frequent plot device is the idea of a power struggle. Percy might be in a situation where he has to fight off other forces that want to take advantage of his weakened state while he's holding up the sky. This could involve battles with mythical creatures or other malevolent demigods. Another common device is the exploration of Percy's heritage. Maybe while under this great strain, he discovers some long - lost aspect of his family history that gives him the strength to keep going. Also, time manipulation is sometimes used. The time Percy spends holding up the sky might be different in the mortal world compared to the demigod world, which creates interesting plot twists.
In these fanfictions, a common plot device is the cultural exchange. Hermione could introduce Edward to things like Butterbeer and magical games, while Edward could show Hermione the beauty of the vampire world at night. There's also the plot device of identity crisis. Hermione might question her place in the wizarding world if she falls in love with a vampire, and Edward might wonder how he fits into Hermione's world. And sometimes, there's the plot device of a prophecy or a magical bond that ties them together, which forces them to be together despite all the odds and difficulties from their different backgrounds.
In many such fanfictions, the power struggle plot device is used. If Sakura becomes too powerful or tries to assert her dominance in a way that overshadows Naruto and Hinata's relationship or their own achievements, they might start to hate her. For example, if Sakura gets a high - ranking position in the village and starts making decisions that affect Naruto and Hinata negatively, it can fuel their dislike. Another aspect is the character arc plot device. The writer might give Sakura a negative character arc where she becomes more self - centered or greedy, which would make Naruto and Hinata dislike her.
One common plot device is the introduction of a new mentor figure. This person could be an older student, a former Hogwarts graduate, or even a magical creature. They guide Harry in his studies, offer advice on how to handle difficult subjects and professors.
One common plot device is the discovery of ancient artifacts or prophecies that link Harry to Merlin. For example, a magical amulet that was once Merlin's might be found and react only to Harry. Another is the appearance of a character who knew Merlin in the past and recognizes Harry as his reincarnation.
A plot device could be Cedric getting involved in Harry's personal quests. For instance, if Harry is trying to figure out something about his parents, Cedric may insert himself into the situation, believing he can protect Harry better that way. He might also try to monopolize Harry's time for training or studying, which could lead to some tension between them as Harry might feel smothered.