In some fanfics, the basilisk can be a source of great power for Harry. He might absorb some of its magic or gain a special ability after a close encounter with it.
It could play a major role as a plot device. For example, it might be a key ingredient in a potion that can cure a deadly disease in the wizarding world.
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.
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.
They often make the Basilisk a more complex character. Instead of just a monster, she could be a protector in some fanfics. For example, protecting a hidden area in Hogwarts.
In some Harry Potter fanfiction, the basilisk auction at Gringotts could be a very dangerous and illegal affair. It might involve dark wizards trying to obtain the basilisk for its powerful and deadly abilities, like its petrifying gaze. Maybe it's a way for the author to explore the seedy underworld of the wizarding world where such dangerous magical creatures are traded on the black market.
They could also be used in some form of dark magic defense. Snape might use the basilisk parts to create spells or enchantments that can protect Hogwarts from dark creatures or dark wizards. Maybe he could create a magical barrier using the basilisk parts' power that repels any dark magic approaching the school.
In some Harry Potter fanfic, Basilisk poison is often depicted as extremely deadly. It can quickly incapacitate and kill the victim. For example, in many fics, it spreads through the body rapidly, causing intense pain and organ failure. Just a small amount can be fatal.
Obviously, Harry Potter would be one of the main characters. He's the hero of the original series and would likely play a central role in any fanfic about the basilisk. Hermione Granger would probably also be there, using her intelligence to help solve the problems related to the basilisk.
In many fanfics, Basilisk blood is depicted as a very dangerous substance. It's often shown as a thick, greenish - black liquid that hisses and steams when exposed to air, reflecting the Basilisk's own menacing nature.
One common theme is redemption. Many fanfics explore the idea of the basilisk having a chance to atone for its actions, like in 'A Basilisk's Redemption'. Another theme is mystery. Fanfics often try to uncover more about the basilisk's origin and its true nature, as seen in 'The Secret of the Basilisk'.