His friends like Han Solo and Leia would be deeply affected. They would either try to save him or be forced to fight against him. This would create a great internal conflict within the group that once fought together against the Empire. Also, Luke's turn could inspire other young Force - sensitive individuals to follow the Dark Side, thinking that he has found a better path.
If Luke turned to the Dark Side, the Rebellion would be in a very difficult position. He was a symbol of hope and a powerful Jedi. Without him on their side, the morale of the Rebellion would drop significantly. The Empire, on the other hand, would gain a very powerful ally. Darth Vader might even try to make Luke his apprentice, and together they could become an almost unstoppable force.
If Luke turns to the Dark Side in fan fiction, the story would take a very different turn. The relationship dynamics would be completely altered. His friends like Chewbacca, who had fought beside him, would be in shock. His fall could also inspire other Jedi - in - training to question their own paths. Maybe some would be tempted to follow him into the Dark Side. And the Emperor, if still alive, would have a new tool to use against the remaining Jedi and the Rebellion. He could use Luke to spread fear and chaos, which would be a very different plot from the original Star Wars stories.
It could introduce new storylines. For instance, if she has a unique connection to the Force, it might change how the Jedi are perceived. Maybe she has a different approach to using the Force that challenges the traditional Jedi ways.
If Luke Skywalker were a pirate in Star Wars, it would completely transform the classic story. For one, his relationship with the Force might be used in a more self - serving way at first. Instead of being a Jedi knight on a noble quest, he could be using his powers to raid Imperial ships for treasures. His costume would likely be a mix of pirate garb and traditional Jedi robes, creating a very unique look. Also, his allies and enemies would shift. He might team up with smugglers more often and be hunted by the Empire not just for being a Jedi but also for being a pirate disrupting their trade routes.
The power balance would be severely disrupted. The Rebellion would lose one of its most important leaders, and the Empire or any other dark side - aligned forces would gain a significant advantage. Her knowledge of the Rebellion's strategies and bases could be used against them.
In many Star Wars fanfictions, a 'Dark Luke Skywalker' is a fascinating concept. It often shows a different path Luke could have taken. Maybe if he had given in to the dark side during his training or due to some great loss. This version of Luke can be extremely powerful and menacing, with a different set of abilities compared to his canonical self.
The consequences would be huge. The Resistance would lose one of its most powerful allies. It would also mean a new threat to the galaxy. Rey's turn to the Dark Side could inspire others to follow her, leading to a resurgence of the Sith. The balance of the Force would be severely disrupted.
Maybe in the fanfiction, Luke witnesses something so devastating that he loses faith in the Jedi way. For example, if the Jedi Order fails to prevent a great catastrophe. This could push him towards the Dark Side as he seeks a more radical solution to bring order. He might start using aggressive and unethical means, like Vader did, believing it's for the greater good.
It could be a new Sith Lord created specifically for the fanfiction. This new character could be more powerful and devious than any before. He could be the one who lures Luke to the Dark Side and then becomes his enemy as they compete for power within the Dark Side hierarchy.
Another plot could involve a powerful Sith Lord who manipulates Luke. The Sith Lord could use Luke's insecurities, like his fear of not being strong enough to protect his friends. He could be tricked into believing that the Dark Side would give him the power he needs, and slowly turn to the dark side as a result.