It could also involve some sort of prophecy alteration. Maybe there is a hidden magical object that can change the course of prophecies. Harry finds this object and uses it to rewrite the prophecy that led to his parents' deaths, thus saving them. This would be a very creative and complex plotline, but fanfiction allows for such bold ideas.
Another approach could be that Harry gains some super - powerful new magic. This new magic could be related to love, which is a very powerful force in the Harry Potter universe. He realizes that his love for his parents can be manifested as a protective and offensive magic. So, when he faces Voldemort, he uses this love - magic to defeat him and save his parents.
In theory, it is possible in fanfiction. One way could be through time - travel magic. Harry could discover a powerful time - turning spell that allows him to go back in time to the moment before his parents' deaths. He would then use his skills and knowledge from his own time to fight off Voldemort and save them. For example, he might use advanced defensive spells he learned at Hogwarts to counter Voldemort's attacks.
Well, in fanfiction, it might be that a magical object has the power to bring the dead back to life. For example, a long - lost and extremely powerful enchanted amulet. When Harry discovers this amulet, it has the ability to restore his parents to life. It could also be that a benevolent and extremely powerful being decides to intervene and resurrect the Potters for the sake of Harry and the greater good of the wizarding world.
One possible reason could be that he might feel abandoned. Growing up without them, he could resent the fact that they left him an orphan. He might think that if they were really so great, they would have found a way to survive and be there for him.
Another difficulty is character consistency. Harry is a character who grew up without his parents, and this has shaped his personality. If he saves his parents, his character development could be completely different. Writers need to carefully consider how to keep Harry's essence while changing such a major plot point. It's not easy to balance the new, happy - family - oriented Harry with the original, somewhat brooding and determined Harry.
One possible reason could be a misunderstanding. Maybe he discovers some secrets about his parents that he misinterprets. For example, if he finds out they were involved in some dangerous or morally ambiguous activities in their youth that he doesn't fully understand at first.
One possible reason could be that he discovers some long - hidden family secrets that make him question his parents' actions or decisions. Maybe he finds out about some dark deeds in their past that he can't overlook.
One possible reason could be that in the fanfiction, Harry might have discovered some dark secrets about his parents that made him feel betrayed. For example, if he found out they had some hidden and unethical magical experiments in their past.
Perhaps he discovers some secrets about his parents that he doesn't like. For example, he might find out that they were involved in some dangerous or unethical magic before. This new knowledge could make him angry at them for putting themselves and their family in jeopardy.
One possible reason could be that in the fanfic, the author might twist the story to make it seem like his parents' actions had unforeseen consequences that affected Harry negatively. For example, their fight against Voldemort led to Harry being an orphan and having to bear a great burden from a young age.
Well, it could be for the sake of exploring a different kind of magic or a different set of rules in the wizarding world. Perhaps in this fanfiction's version, the parents were under some sort of dark magic influence that made them turn on Harry. Or it could be a psychological exploration. The writer might be interested in delving into the minds of Harry's parents and seeing what could make them do such a heinous act. It could also be just a very different take on the concept of family and love in the 'Harry Potter' universe.
One possible plotline could be that Harry discovers a plot against Snape before it's too late. Maybe he overhears some Death Eaters planning to ambush Snape while he's on a solitary mission. Harry then uses his invisibility cloak and magic skills he's learned over the years to outwit the Death Eaters and save Snape. This would show Harry's growth as a wizard and his ability to set aside past differences with Snape.