A possible development is that the wizarding world would be divided in their view of Harry. Some would see him as a threat because of the basilisk - associated eyes. This could lead to Harry having to fight not only the dark forces but also the prejudice within the wizarding community. He would have to prove that he is still the same Harry, just with a new and strange ability.
In the fanfiction, the plot might revolve around Harry trying to find a way to reverse this change if he doesn't want the eyes. Or, he could embrace it and start a new journey to learn more about the basilisk and its magic. Along the way, he could meet new characters who are either experts on basilisks or also have some strange, related abilities.
The basilisk eyes in Harry Potter fanfiction often symbolize death and petrification. Some fanfictions might explore what would happen if someone managed to resist the petrifying power of the eyes through some unique magic or strong will. It could lead to interesting character development as they face this deadly threat.
A fanfiction where Harry Potter has Basilisk eyes could explore his relationship with snakes in a new light. He might be able to communicate with them on a deeper level, like Parseltongue but more intense. This could lead to him befriending some snakes and using them as allies. He could also have to deal with the prejudice from those who fear the power of the Basilisk, thinking he might turn evil because of his connection to such a feared creature.
The story could develop with Harry trying to figure out how to turn back. He might search for ancient spells or magical artifacts that can reverse the transformation.
Harry would likely become more feared by some in the wizarding world. Since the Basilisk is often seen as a terrifying and dangerous creature, his connection to it might make others view him with suspicion. He would also have to grapple with the darker side of magic that the Basilisk represents, which could make him more brooding and introspective.
Dumbledore could also be involved. He's extremely knowledgeable and powerful. He might have some secret knowledge about basilisk eggs. He could guide Harry on whether to keep the egg or destroy it, depending on the greater good of the wizarding world.
The story could develop with Harry's friends trying to bring him back from the brink. They might search for a way to reverse whatever has made him lose his will to live. For example, if it's a curse, they could look for a counter - curse. Another way could be that Harry has a moment of self - realization and decides to fight back against the despair. Maybe he has a vision or a talk with a ghost from his past that gives him a new perspective.
In fanfiction, Harry having the eyes of a basilisk might be a creative way to explore his character in a new light. It could change how he interacts with others. For example, some might be repelled by his new appearance, while others might see it as a sign of his special status. It could also lead to new storylines, like him having to hide his eyes or learning to control the power that comes with having basilisk - like eyes.
They can be a source of mystery. Writers might use the basilisk eyes to hide secrets. For instance, there could be a hidden message that can only be seen when looking into the basilisk eyes under a certain magical condition in a fanfic.
In some fanfictions, basilisk eyes can be a source of dark magic. They might be used by dark wizards to cast powerful and malevolent spells. For example, a dark wizard could use the basilisk eyes to create a fear - inducing spell that spreads across Hogwarts.
Well, in fanfiction, anything can happen. Maybe a spell gone wrong created a situation where the basilisk became friendly towards Harry. Or perhaps there was some kind of magical bond formed through a unique event in the fanfic's alternate universe.