A great plot idea could be that the Basilisk was not just a mindless monster but was actually being controlled by an unseen force all along. This force could be an ancient spirit or a powerful dark wizard from the past who was using the Basilisk to carry out their evil plans. Harry and his friends would then have to not only defeat the Basilisk but also uncover the identity of the mastermind behind it. Another plot could be about the Basilisk's venom. What if there was a way to use the venom for good, like creating a powerful antidote to a new and deadly dark magic spell? The characters would have to figure out how to safely extract and use the venom without getting killed by the Basilisk.
Yes, there are likely many 'Harry Potter Basilisk' fanfictions that don't involve mpreg. Fanfiction is a vast genre, and while mpreg might be a niche concept, there are numerous stories that focus on other aspects such as the battle between Harry Potter and the Basilisk, or the mystery and magic related to the Basilisk in a more traditional sense. You can search on popular fanfiction websites using keywords like 'Harry Potter Basilisk' and then filter through the results to find the ones that suit your taste.
One interesting 'Harry Potter Basilisk' fanfiction could be one where the Basilisk has a more complex backstory. Maybe it was once a normal snake that was corrupted by dark magic. Another could be a story where the Basilisk forms an unexpected bond with a Hogwarts student other than Harry. For example, a Hufflepuff student who discovers the Basilisk's lair by accident and instead of fighting, they try to understand it.
A plot could revolve around a hidden prophecy that links the Basilisk and the Patronus. A young witch or wizard discovers this prophecy and realizes that they are the key to either saving or destroying the wizarding world. They must then navigate the dangerous relationship between the two magical entities. This could involve traveling back in time to learn about the origins of the Basilisk and the true nature of the Patronus magic, which could be much deeper and more complex than what was taught at Hogwarts.
In a fanfiction, the Phoenix and the Basilisk could be two parts of an ancient prophecy. Harry Potter is the one foretold to either unite them or destroy one to save the other. Along the way, he has to learn about the true nature of both creatures. He might find that the Basilisk isn't as purely evil as it seems and the Phoenix has a more complex role than just being a symbol of good. This could lead to a very engaging story full of moral dilemmas and exciting magical encounters.
A great plot for fanfiction could be a time - travel story. A wizard travels back in time to the era when the basilisk was first created or brought to Hogwarts. With the help of a special wand, they try to change the course of history regarding the basilisk. But every change they make has unforeseen consequences. For example, they might prevent the basilisk from being killed in the past, which then creates a new and more dangerous threat in the present. So, they have to find a way to fix what they've messed up while still dealing with the power of the basilisk and the wand.
One interesting 'Harry Potter x Basilisk' fanfiction could be one where Harry discovers he has an unexpected connection with the Basilisk. Maybe he can communicate with it in Parseltongue and tries to understand its motives beyond just being a dangerous creature in the Chamber of Secrets.
One plot idea could be that the male basilisk is actually a cursed wizard who can only take the form of a basilisk. Harry discovers this and tries to find a way to break the curse. Another could be that the basilisk has a special power that can help Harry in his fight against Voldemort, so they form an alliance.
A great plot idea could be that the female basilisk is actually a guardian of an ancient wizarding secret. Harry stumbles upon her while exploring a hidden part of Hogwarts. Instead of fighting, they form an alliance to protect the secret from dark wizards who are also seeking it. This would focus on mystery, adventure and cooperation rather than any inappropriate themes.
One interesting fanfiction could be about a character who has a special connection with the basilisk eyes. Maybe they can see visions through the eyes, like seeing the past secrets of Hogwarts that the basilisk might have witnessed. Another could involve a spell that uses the power of the basilisk eyes in a new and unexpected way, for example, to unlock a hidden chamber in Hogwarts that was previously unknown.
In 'harry potter basilisk hybrid fanfiction', there might be a focus on the hybrid's origin. Maybe it was created by dark magic gone wrong or as an experiment. It could also explore the hybrid's relationship with other characters. Like, would Hermione try to understand it scientifically? Or would Ron be afraid of it at first? And perhaps there are adventures where the hybrid uses its combined abilities to overcome challenges in the wizarding world.