Another consequence could be related to the balance of magic. Dementors play a certain role in the magical ecosystem, so their destruction might disrupt this balance. Harry might then have to deal with the unforeseen effects of this imbalance, such as new magical threats emerging or changes in the behavior of other magical creatures. He would have to take responsibility for his actions and try to find a way to restore some sort of equilibrium in the wizarding world.
However, there could also be negative consequences. Some people in the wizarding world might be afraid of Harry's new - found power. They might think that he is becoming too powerful and could pose a threat to the established order. This could lead to some people trying to isolate or even target Harry.
One possible consequence is that the wizarding world might see Harry as a hero even more than before. After all, dementors are very dangerous creatures, and if he manages to destroy them, it's a huge accomplishment.
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.
He might become a hero in the eyes of some people. But he could also be feared by others who see his power as a threat.
There could be some negative consequences too. Maybe the dragon had some kind of magical protection or was under the care of a powerful wizard or creature. Harry might then face the wrath of those who were protecting the dragon, leading to him having to go into hiding or facing dangerous challenges. Also, the act of killing a dragon, even in self - defense, might make some more sensitive wizards view him in a different, less favorable light.
He might gain more respect from his peers. After all, killing the Basilisk is no small feat. His friends would probably look up to him even more, and his reputation in Hogwarts could soar. He could also become a bit of a legend among the younger students.
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.
The wizarding world might be in shock. People who have always seen Voldemort as the ultimate evil would be confused. They would have to re - evaluate their views on Voldemort. Harry, on the other hand, would be in a very strange situation. He might be distrusted by some of his friends who think he has made a deal with Voldemort.
Socially, his status as a hero might change. Some might see him as weakened and no longer the invincible hero. This could lead to a shift in the wizarding community's perception of him, and he might have to work hard to regain his former standing.
Well, if Harry gets rid of Snape, he might face backlash from the Slytherin house. Snape was a Slytherin and had his supporters there. They could make Harry's life difficult in various ways, like spreading rumors or trying to undermine his achievements. On the other hand, Harry might find new allies. Those who were secretly afraid of Snape but couldn't do anything might now side with Harry. But he also has to be careful not to let this new - found power go to his head, or he could end up making more enemies in the long run.
He might gain some extraordinary magical abilities. For example, he could be able to control time or have a deeper understanding of magic spells that were previously difficult for him.
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.