A more complex plotline might be that Harry forgets his past but still has an instinctual sense of danger. He could be drawn to the places and people related to the fight against Voldemort without knowing why. This would make him a bit of an enigma to both the good and bad sides, and they would all try to figure out what he does and doesn't know.
One interesting plotline could be that Harry forgets his magical abilities. He then has to rediscover magic in a completely new way, which could lead to him seeing the wizarding world from a fresh perspective. For example, he might start to question the norms and traditions of Hogwarts that he previously took for granted.
One possible plotline could be Harry's friends trying desperately to help him regain his memory. They might use magic spells or show him familiar objects from his past. Another plotline could involve Harry having to relearn about the wizarding world and his own identity while facing new threats that don't know he has lost his memory. Maybe he even has to start from scratch at Hogwarts, making new friends and enemies all over again.
One possible plotline could be Naruto having to relearn all his ninja skills with only one arm. He might struggle at first but then discover new ways to perform jutsus, like using his legs more for balance and chakra control. Another could be his friends trying to find a way to restore his arm, leading them on a dangerous journey to find a rare artifact or a powerful healer.
Well, a possible plot could be that Snape loses his memory due to a powerful dark magic spell gone wrong. He forgets his identity completely. The story could then focus on how the other Hogwarts professors try to help him. For example, Dumbledore might use some ancient magic to try and restore his memories. Meanwhile, Voldemort could sense that something is off with Snape and send his Death Eaters to investigate. This would create a lot of tension and drama in the story.
Another plotline could be that Artemis, without her memory, starts to develop new relationships and a different personality. Percy could be conflicted about whether to try and bring back the old Artemis or let this new version of her exist. Meanwhile, the other demigods might be suspicious of this changed Artemis, and Percy has to convince them to give her a chance. This could lead to a lot of internal drama among the demigod community as they deal with this unexpected situation.
One plotline could be Snape forgetting his past enmities, especially towards Harry Potter. This might lead to an unexpected friendship developing between them as Snape no longer holds the grudges from before. He could start seeing Harry in a new light and they might work together to uncover secrets about the wizarding world that were previously clouded by their animosity.
Perhaps in this fanfiction, Goku remembers all his past battles vividly. This could lead to him having unique strategies against old foes. For example, when facing Frieza again, he recalls every single move Frieza made during their previous encounters and is able to counter them with ease, making the fight much more one - sided in his favor.
One possible plotline could be Ruby's struggle with self - image. Losing an eye would be a huge change for her. She might have to adapt to new ways of fighting and seeing the world. Another plotline could involve her relationships. Her friends would likely be very concerned and protective, which could lead to some interesting character dynamics.
One interesting plotline could be Harry forming an unlikely alliance with some Slytherins to solve a mystery within Hogwarts. Maybe they work together to figure out the origin of a strange magical occurrence in the Forbidden Forest.
One possible plotline could be that Naruto's son is kidnapped by an old enemy seeking revenge. Naruto then embarks on a journey filled with self - doubt as he struggles to find his son. He may have to face his own past mistakes and enemies he thought were long gone.
One possible plot twist could be that Percy forgets not only his past but also his special abilities. So he has to relearn everything from scratch, and in the process, discovers new and unexpected powers within himself. This could lead to him being seen as a threat by some and a savior by others in the fanfiction world.