Often, there's a plot twist where some magical interference or prophecy was involved in hiding the truth. Maybe a powerful wizard or witch cast a spell to make everyone believe Harry was James' son when in fact he was Snape's. And then, as the fanfiction unfolds, there are signs and clues that start to surface. Like, Snape's strange behavior towards Harry throughout the years at Hogwarts might be because he was his father but couldn't show it. It creates a really interesting re - imagining of the relationships in the 'Harry Potter' world.
One plot twist could be that Snape discovers Harry is his son right before a major battle. This new knowledge gives him the extra motivation to fight even harder to protect Harry. Another could be that Voldemort finds out about this relationship and tries to use it against them both, perhaps by threatening to harm Harry if Snape doesn't turn on Dumbledore.
One common plot twist is that Snape was forced to hide his fatherhood due to some dark magic threat. Another could be that Harry's mother had some sort of pre - arranged deal with Snape that led to Harry's birth.
One main plot twist could be the revelation of Snape's true relationship to Harry. This would completely change Harry's view of himself and Snape. Another could be how the wizarding world reacts to this news. People who once hated Snape might have to reevaluate their opinions, and those who thought they knew Harry's family history would be shocked.
Well, often in these fanfictions, a plot twist is that Snape enters with a secret mission related to Harry. It could be that he has been working undercover for a group that wants to protect Harry from a greater threat than Voldemort. Or, Snape enters and it turns out he has a connection to Harry's magic that was previously unknown. For example, he might be able to unlock a new level of Harry's powers. Also, Snape could enter in a scenario where he and Harry are forced to swap bodies, which leads to all kinds of humorous and also deep - understanding - building situations between them.
A common plot twist could be that Snape is actually Harry's real - life protector all along. He pretends to be mean in public but in private, he is training Harry for some greater purpose. Another could be that Snape's niceness is part of a deal he made with Dumbledore that we don't know about in the original story. Maybe Dumbledore asked Snape to be extra nice to Harry to boost his confidence.
In many of these fanfictions, a common plot twist is the exploration of Snape's past relationship with Lily in light of this new information. Maybe there were more secret meetings or promises made between them that Harry uncovers. Another plot twist could be that the wizarding world's view of Snape completely changes when the truth is revealed, and Harry has to deal with the new - found fame or notoriety that comes with being Snape's son. Also, there could be a plot twist where Harry discovers that Snape had been training him in subtle ways all along, without Harry realizing it was his father - son connection at play.
In most fanfictions, the evidence is often fabricated within the fictional narrative created by the author. It could be things like hidden memories, secret meetings in the past that were never revealed in the original series, or some magical bond that was only known to a few. However, in the original 'Harry Potter' canon, there is no such relationship between Harry and Snape.
One possible plot twist could be that Snape has a hidden agenda all along. Maybe he's been using Harry as a pawn in a bigger scheme related to the wizarding world's power struggle. Another could be that Harry discovers a long - lost family connection to Snape that changes their dynamic completely.
One common plot twist is when Lily discovers Snape's deeper involvement with the Dark Arts later than expected. This realization makes her lash out at him more harshly than before, causing great pain. For instance, she might find out about some of his secret experiments or associations.
A possible plot twist could be that Merlin is not actually dead but has been trapped in a different dimension. Harry, as his son, has to find a way to free him. This would completely change the dynamic as they could then fight side by side against the forces of evil.