Luke could also react with anger. He might see it as Vader trying to manipulate him further, especially if he has recently suffered losses at the hands of the Empire. His anger could fuel a desire to prove Vader wrong and show that he will never be part of the Empire's dark legacy, leading him to redouble his efforts to fight against Vader and the Imperial forces.
He might feel conflicted. On one hand, there could be a part of him that is intrigued by the power and influence that comes with being Vader's heir. But on the other hand, his loyalty to the Rebel cause and his Jedi ideals would be pulling him in the opposite direction. He may struggle with whether he can use this new position to bring about positive change in the Empire or if he should reject it outright.
The relationship between the Empire and the Rebel Alliance could also be affected. The Rebels might see Luke's new position as an opportunity to infiltrate and change the Empire from within. On the other hand, some in the Empire may try to use Luke as a bargaining chip to negotiate a truce or peace deal with the Rebels, which would completely change the nature of the galactic conflict.
One reason could be that Vader represents the dark side which has brought so much destruction in the galaxy. Luke, being on the side of the Jedi and good, would naturally despise the evil deeds associated with Vader.
Vader might initially be shocked. His son reaching out to him is unexpected. He could respond with a moment of silence, trying to process what is happening.
Well, Vader discovers Luke is his son when their paths cross in a crucial battle. Clues and Force visions lead him to the realization. It's a major plot twist!
In many such fanfictions, their relationship becomes more positive. Vader starts to see Luke as a chance for true redemption. He may become more of a mentor to Luke, sharing his knowledge of the Force.
This would be a huge twist. It might mean Luke is seduced by the dark side's power or has some ulterior motive for joining Vader. It could change the course of the entire story.
There's a fanfic titled 'Vader's Redemption'. In this story, Vader starts to question his loyalty to the Emperor much sooner, especially after some profound encounters with Luke. It's a great read as it shows the internal struggle of Vader while also exploring the bond between father and son in a new light. It's full of action-packed scenes and deep emotional moments.
Often through his internal thoughts. The fanfiction might describe Luke seething with anger whenever he thinks of Vader. For example, in some stories, when Luke is meditating, his thoughts are constantly interrupted by visions of Vader and his past actions, and he can't focus because of his hatred.
It's a tense and dramatic showdown. Luke faces Vader with a mix of fear and determination, leading to a powerful confrontation.
The relationship could develop in a complex way. Since Vader has captured Luke, there's a power imbalance. However, as they interact, Luke might try to reach out to the good in Vader. Vader, in turn, might be conflicted. He could start to protect Luke from the Emperor's harsher plans, leading to a strange alliance within the captivity.