Maybe Arya gets caught trying to save Ned at the last moment and is taken prisoner. This would be a huge twist as it changes her whole path from being a free - roaming girl to a captive of her enemies.
One possible twist could be that Arya witnesses a person who she thought was an ally actually being the one who orchestrated Ned's execution in a more devious way. This would completely shatter her trust and set her on a new path of vengeance against this unexpected enemy. Another twist could be that right after the execution, Arya is whisked away by a mysterious figure who has their own plans for her. This figure could be from a far - off land or have some hidden agenda related to the Stark family's future.
Well, it would likely make her more vengeful. Seeing her father unjustly executed would fuel her desire for revenge against those responsible, like the Lannisters. This could accelerate her journey towards becoming a more hardened assassin.
A plot twist could be that when Arya saves her mom, they find out that there was a prophecy involved all along. The prophecy states that Arya's actions will set off a chain of events that will either save or doom the Seven Kingdoms. Now they have to decide what to do with this newfound knowledge and whether to act on it or try to keep it a secret.
One possible plot development could be that Ned gains new political insights from Renly. Renly might share his ideas about ruling and power, which could make Ned reevaluate his own stance. For example, if Renly has a more liberal view on how to deal with the common people, Ned could start to consider implementing some of those ideas in the North.
Another idea is that Arya uses her skills in a completely new and unexpected way. Instead of relying on her typical stealth and combat skills, she might use her wits to manipulate the situation. For instance, she could spread false rumors among the captors that would cause chaos and confusion, allowing her to slip in and save Ned.
A really interesting plot twist might be if Arya discovers that her pregnancy is part of a political plot against her or her family. This would force her to use her skills and wits to protect herself and her unborn child, similar to how she had to survive in the original series. It could also lead to her reuniting with long - lost family members or making new alliances. Well, in this fanfiction, she would have to navigate through a whole new set of challenges with the added responsibility of a pregnancy. She might even have to pretend to be someone else to keep her pregnancy a secret from her enemies. This would be a great way to see her character develop further in a different context.
A great plot twist would be if Arya's gag was part of a larger scheme by the Faceless Men. They could be testing her in a new and extreme way. Maybe they want to see if she can still carry out her assassinations without being able to speak or use her normal methods. This would put her skills and training to the ultimate test.
If Arya killed Joffrey in a fanfic, one possibility is that she would become an instant target for the Lannisters. They would stop at nothing to avenge Joffrey's death. Arya would have to go into deeper hiding or rely on her Faceless Men training even more. Maybe she'd have to flee across the Narrow Sea and start a new life in Essos, constantly looking over her shoulder for Lannister assassins.
The twin's recognition of Arya could also lead to a change in Arya's character arc. Up until that point, Arya may have been operating in a certain way, but the encounter with the twin makes her reevaluate her goals. If the twin is a positive influence, Arya might start to consider more peaceful or diplomatic solutions to the problems she faces. On the other hand, if the twin has ulterior motives, Arya could become more guarded and distrustful, further hardening her already tough exterior.
A plot twist could be that Ned Stark's son Arya (disguised as a boy for most of her journey) is actually a secret weapon trained by the Faceless Men not just for personal vengeance but to be a political pawn. She could be used by some powerful force to manipulate the balance of power among the kingdoms.
One possible scenario could be that Arya is captured by an enemy. Maybe she was infiltrating a stronghold and got caught, and they tape - gagged her to prevent her from using her wits and words to escape or call for help. Another situation might be that she is held captive by someone who doesn't want her to reveal certain secrets she has learned during her travels. For example, if she discovered something about a powerful family's plot, they would want to silence her quickly.