One consequence could be that the wizarding world is in shock. Dementors are usually just sent away or repelled, not killed. So, the Ministry of Magic might be very concerned about this new development and start to investigate Harry.
Well, it could be that in this fanfic, Harry has some sort of special artifact or weapon. For example, he might find an ancient magical object that has the power to vanquish dementors. He figures out how to use it and thus is able to kill the dementors. It could also be that he has made a special connection with some magical being or force that gives him the strength to take on the dementors in a more lethal way.
One way is through group support. If characters are together, they can draw strength from each other. For example, Hermione could use her knowledge to come up with a plan. Ron could offer his loyalty and courage. And they could all hold hands and face the Dementors together. Also, they might find some magical artifacts that can help, like a special amulet that gives them a sense of calm when Dementors are near.
There are a vast number of fanfictions in the Harry Potter fandom, and it's quite possible that there is one where Harry Potter kills dementors. FanFiction.net has a huge collection of Harry Potter - related fanfictions. Another option is to check out Wattpad, although it has a more diverse range of stories including non - HP specific ones. When you search, make sure to be as specific as possible in your search terms to increase your chances of finding the relevant fanfiction.
In many Harry Potter fanfics, the concept of dementors often adds a dark and mysterious element. When it comes to wand cores, there could be a fanfic where a character discovers a new type of wand core that has been affected by dementor magic. This could lead to a whole new set of spells and abilities for the wizard or witch who wields it. The wand might have an affinity for dark arts - like spells, but also might be able to counteract the effects of dementors on a person's soul, creating a very complex and morally ambiguous magical item.
In many fanfictions, Dementors are used as a tool to create a sense of despair. For example, when a character is facing a Dementor, their worst memories are brought to the surface, and this can be used to develop the character further. The fanfictions might also show how different characters react to the Dementors in different ways. Some might be paralyzed with fear, while others might try to fight back using magic like the Patronus charm.
Well, it would be a really dark take. Harry would probably be constantly in a state of near - despair. Since Dementors are soul - sucking creatures, he might have a hard time forming normal relationships. His view of the wizarding world would be very different from the original story. He might see it as a place full of threats and darkness rather than a place with some good in it. And his Patronus, if he could even produce one, would be very weak or have an unusual form.
One consequence could be that the wizarding world starts to view him with even more suspicion and fear. People are already afraid of dementors, and if Harry can control them, they might think he's becoming too powerful or even turning to the dark side.
It could also be due to his own inner strength and growth as a wizard. Harry has faced so many challenges and traumas throughout his life. His experiences might have awakened a latent power within him that allows him to control dementors. His strong willpower and determination, which have been developed over years of fighting against the dark forces, could be the key factor in this newfound ability.
Well, in some fanfictions, Harry might use a super - powered Patronus. His Patronus could be stronger than usual, perhaps due to some newfound magic or a special connection he has developed. It could be so powerful that it simply overpowers the dementors and destroys them.