Another plotline might be that Percy betrays God out of a sense of self - preservation. Suppose there's a great threat coming, and Percy believes that siding with an enemy of God is the only way to save himself or the world he cares about. He might think that God's power is not enough to protect them, and so he makes a deal with the other side, which is seen as a betrayal.
Perhaps Percy betrays God because of a misunderstanding of God's plan. He could be impatient with God's slow - moving grand design. He might see a more immediate solution to a problem that goes against God's will. For instance, if there's a plague affecting his people, and God's plan is to let it run its course for some greater good, Percy might take matters into his own hands and use forbidden magic or make deals with dark entities, which is considered a betrayal.
One possible plotline could be that Percy is under some sort of mind control. Maybe a new villain has the power to manipulate his thoughts and actions, making him turn against Annabeth. For example, the villain could use Percy's insecurities about his past mistakes to drive a wedge between them. He might start by leaking some of Annabeth's secret plans to the enemy, causing her to be in danger without realizing Percy is the source.
One possible plotline could be that Harry betrays Draco in a duel. Maybe there was some sort of misunderstanding or a secret deal that Harry made with someone else that required him to turn on Draco during the duel. For example, if there was a dark wizard threatening Harry's friends and the only way to save them was to sacrifice Draco in the duel by using a forbidden spell against him.
One possible plotline could be that Ash is influenced by a powerful and evil force. This force convinces Ash that Cynthia is somehow a threat to his ultimate goal, like becoming the greatest Pokémon trainer. So, he betrays her by stealing a crucial Pokémon of hers during a big tournament. This would lead to a lot of drama and conflict as Cynthia would be shocked and heartbroken, and Ash would start to realize the error of his ways as the evil force begins to control him more.
Perhaps Harry discovers a dark secret about the side he has been fighting for. This discovery makes him feel betrayed and he turns to Tom thinking that Tom offers a different kind of solution. It could be that Tom presents himself as a reformed person or has a convincing argument about a new order in the wizarding world that Harry, in his disillusioned state, starts to believe. Then, the story could follow how Harry's relationships with his old friends deteriorate as he gets closer to Tom's side.
In some fanfictions, Percy might betray Natasha due to his own ambition. He could see an opportunity to gain more power or status by siding against her. For example, if there's a power struggle within their group or world, and he thinks that by betraying Natasha, he can get on the winning side and be rewarded. It could also be a case of jealousy. If Natasha has always been in the spotlight or has more skills and abilities, Percy might feel overshadowed and his jealousy could lead to betrayal.
One possible plotline could be that Akeno is forced to betray Naruto due to some external threat or blackmail. Maybe an enemy has something over her that she values greatly, like the safety of her friends or family in her own world. So, she has to act against Naruto to protect them.
Perhaps in the fanfic, Ash betrays Tyson because of a misunderstanding. There could be a false rumor spread about Tyson being involved in some unethical Pokémon training methods. Ash, believing the rumor without fully investigating, turns his back on Tyson. Later, when he realizes the truth, he has to work hard to regain Tyson's trust.
One possible plotline could be that Snape remains a loyal Death Eater throughout. He continues to carry out Voldemort's orders without question. Maybe he helps Voldemort in his search for more powerful dark magic, and in this version, he has no hidden motives of protecting Harry or the Order. He is fully committed to the Dark Lord's cause, which could lead to a much darker and more hopeless situation for the wizarding world.
One possible plotline could be that Leo and Percy are in a dangerous situation together, like being trapped in a magical maze. In the heat of the moment, with all the adrenaline and the realization of how much they mean to each other, they share a kiss. It could be a turning point in their relationship, making them realize their deeper feelings.
Perhaps Percy is lost and ends up in the Japanese mythological world. Amaterasu, seeing his unique powers from a different pantheon, decides to help him find his way back. Along the way, they exchange knowledge about their respective mythologies. Percy teaches her about the Greek gods and their quirks, while Amaterasu imparts wisdom about the Japanese spiritual world. This could lead to a mutual respect and a new friendship that bridges the two mythologies.