There could be a fanfiction where Voldemort saves Harry from another dark wizard. In this scenario, Voldemort has his own motives. He might want to be the one to defeat Harry himself in a more 'honorable' duel later, so he doesn't want some other dark force to take Harry out before he has his chance.
In some fanfictions, Voldemort saves Harry due to a time - travel paradox. Perhaps Harry goes back in time and accidentally changes something that makes Voldemort indebted to him in a way. So, Voldemort has to save Harry to maintain the new timeline he finds himself in.
One interesting 'harry goes to voldemort' fanfiction could be where Harry tries to understand Voldemort's motives and in the process, discovers a long - lost magic that could potentially end the war. Another might be a story where Harry is magically transported to Voldemort's side during a battle and has to pretend to be on his side to survive and gather intelligence.
Well, in some of these fanfictions, Harry's magical abilities might change when possessed. He could start using dark magic in ways he never would have before. It makes for a really interesting twist on his character. For example, he might struggle against Voldemort's will while still being forced to do some dark deeds, creating a complex internal battle.
One interesting fanfiction could be 'The Dark Captivity'. In it, Harry is held in a magically fortified dungeon by Voldemort. Voldemort's motives for capturing Harry are explored in depth, not just about killing him but also about breaking his spirit. Another could be 'Captive Potter'. Here, Harry endures various mental tortures while being Voldemort's captive, but he manages to secretly communicate with his friends using a very unique and magical way.
One interesting 'Harry and Voldemort are soulmates' fanfiction could be the one where they discover their soulmate bond during a magical duel. The intense energy of the duel somehow triggers a connection that neither expected.
One possible fanfiction could be where Harry uses a powerful, ancient magic that he discovers in a hidden chamber at Hogwarts. This magic has the power to reverse death, but he doesn't fully understand the consequences. So, when he brings Voldemort back, Voldemort is initially weak and Harry tries to keep him in check while learning more about this new situation.
In some fanfictions, Harry's sister could be a time - traveler and accidentally end up in a time when Voldemort was still a student at Hogwarts. She then has to interact with him without revealing who she really is or the future she comes from. This creates a complex situation where she might see a different side of Voldemort and question whether he was always completely evil, all while trying to find a way back to her own time.
There are not many mainstream fanfictions with such a strange concept. However, some fan - made works might explore unique power dynamics or symbolic interpretations. Maybe you could search on some specialized fanfiction websites, but be prepared for very unorthodox and often creatively wild takes on the Harry Potter universe.
There might be a fanfiction where Harry Potter begs Voldemort to stop using dark magic on innocent people. In this story, Harry could have seen the destruction Voldemort's dark magic has caused to the wizarding world, especially to the Muggle - borns and their families, and he begs Voldemort to end this chaos.
There are fanfictions that explore Snape's relationship with Voldemort in a more psychological way. For example, delving into how Snape's past experiences with Voldemort shaped his actions throughout the series. Maybe Snape has to face some of his darkest memories related to Voldemort and overcomes them in a unique way in the fanfiction.
One common theme is redemption. It shows Voldemort in a different light, as if he's trying to make up for his past evil deeds by saving Harry. Another theme is the power of change. It's about how Voldemort's actions can change the whole course of the wizarding world. And there's also the theme of complex relationships. It explores how Voldemort and Harry's relationship can be more than just good vs. evil.