In a Harry Potter fanfiction with a giant eye in the lake, the eye could be a manifestation of the lake's magic itself. It might be that the lake is sentient in a way, and the eye is how it observes the activities around it. The plot could involve students being curious about the eye and trying to study it, but their actions accidentally awaken some hidden powers within the lake that start to affect the whole Hogwarts. They then have to find a way to calm the lake again by dealing with the giant eye.
One idea could be that the giant eye is a guardian of an ancient magic artifact hidden in the lake. The protagonist has to figure out how to bypass the eye's watchful gaze without being detected. Another could be that the eye is a cursed object, and when it's removed from the lake, it starts to cause strange and dangerous phenomena around Hogwarts. Maybe it also has a connection to a long - forgotten wizard who used dark magic to create it as a means of protecting his secrets in the lake.
Well, perhaps the giant eye in the lake is actually a sentient being that was once a powerful wizard who was transformed as a punishment. In the fanfiction, the main character might try to communicate with the eye, learning its story and how it ended up in the lake. Or it could be that the eye is a key to a magical portal within the lake that leads to a different dimension, and only those who understand the true nature of the eye can unlock it.
It could be the result of a dark magic experiment gone wrong. Maybe a wizard was trying to create a powerful surveillance spell, but it backfired and created the giant eye instead. The eye then found its way into the lake.
One interesting 'Harry Potter Giant Eye Fanfiction' could be about a magical encounter where the giant eye has a hidden prophecy related to Harry. Maybe it reveals a new threat to the wizarding world that wasn't known before. Another could be a story where the giant eye is a guardian of an ancient and powerful magic that Harry must learn to defeat Voldemort.
One idea could be that the giant squid has a secret ability to communicate with Harry through telepathy. Another could be a story where the squid saves Harry from a dangerous underwater creature. Or perhaps a plot where the squid is actually an ancient magical guardian of Hogwarts that only reveals itself to Harry in a time of great need.
A plot could be that Harry is the only one who can transform into a giant wolf animagus, and he uses this form to hunt down Horcruxes in the most dangerous and inaccessible places. His wolf senses help him detect the dark magic of the Horcruxes more easily.
Another plot could revolve around how he copes with the loss of vision in one eye during his battles. He might have to develop new fighting techniques. Maybe he teams up with a magical creature that can act as his 'extra eye' in a sense, guiding him during duels. This could also lead to a deeper bond between him and the creature.
One idea could be that the scarecrow comes to life and becomes a magical creature that helps Harry Potter in a dangerous task. Maybe it has the ability to sense dark magic and warns Harry of approaching threats.
Perhaps Orochi is a hidden figure in the history of the wizarding world that has been forgotten. Harry discovers some old texts in the Hogwarts library that mention Orochi in relation to a long - lost magical artifact. This leads him and his friends on a quest to find the artifact before it falls into the wrong hands, as it has the power to either control Orochi or be used by Orochi to gain ultimate power over the wizarding world.
One plot idea could be that Harry and Angelina team up for a special Quidditch training session for the younger students. They discover a new flying technique together that gives Gryffindor an edge in future matches. Another could be that they go on a secret mission within Hogwarts to uncover a hidden artifact that has been causing strange magical disturbances. And a third idea is that Angelina gets injured during a match and Harry uses some of his unique magical skills, learned from his various adventures, to help her recover faster than normal.
One idea could be a story where a character has a special power to resist Dementors' effects more than others. Maybe they discover a hidden spell or have a unique magical ability that they use to fight off Dementors when others are in danger. For example, a young witch or wizard who can emit a positive energy that counteracts the Dementors' despair.
One idea could be Norberta getting lost in the Forbidden Forest and Harry has to find her. Another could be Norberta growing ill and Harry, with his knowledge of magical creatures, tries to heal her. Maybe Norberta could get into trouble with some other magical creatures and Harry has to step in to protect her.