There's also a possibility that neither of them initiates it directly. Maybe a situation forces them to be in the same place, and they start to exchange words out of necessity. For example, if they are both trapped in a Sith - created force field and have to work together to break it. In this case, the first words could be more of a practical nature rather than a deep, emotional conversation starter.
However, Luke could also be the one to start the conversation. He is a young and idealistic Jedi, full of hope. He might want to reach out to his father, believing that there is still good in him. He could start the conversation with an attempt to understand Vader's journey to the dark side.
Well, one possible plot could be that Darth Vader tries to persuade Luke to join the dark side once again. Maybe he shows Luke some 'truths' about the Jedi that he believes are lies, trying to shatter Luke's faith in the Jedi way.
I think it might be Nico. Given his experiences with different types of beings in his own world, he might sense the supernatural nature of the Winchesters and approach them first, either out of curiosity or because he thinks they could be allies in his ongoing battles against the forces of the underworld.
It could be Louis. He has always seemed very connected to the group's roots. In fanfiction, he might realize how much the fans miss the band and how much they all still have in common musically. So, he starts reaching out to the other members one by one to see if a reunion is possible.
Goku would be more likely. He is always open to new friendships and challenges. He has a curious nature and would be intrigued by Kefla's power. So he might approach her first to test her strength or just out of friendly curiosity.
A young, Force - sensitive alien who has the power to manipulate time could be an interesting addition. This character could bring a new dynamic to the relationship between Luke and Vader. For example, they might have to protect this alien from the Empire or the Sith who want to use its power for evil.
It could be Naruto. He's known for his boldness and his ability to reach out to people. He might be the one to first notice Korra's unique qualities and be drawn to her, starting conversations and gradually building a connection that could turn into a romantic one.
Yes, there are some interesting ones. You can start by looking on fanfiction websites like Archive of Our Own. There, you'll find various interpretations of their relationship within the Star Wars universe. Some might focus on the redemption aspect of Darth Vader through his love for Luke, while others could explore a more complex emotional bond that defies the typical good - evil dynamic.
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.
If Darth Vader raised Luke and Leia, Luke could be more introverted. He'd have to constantly grapple with the knowledge of his father's actions and his own potential for darkness. His training would be intense, and he might be less likely to trust others easily. Leia would be a more complex character. She would have a love - hate relationship with Vader. On one hand, he's her father, but on the other, he represents everything she hates about the Empire. This would make her personality more unpredictable, sometimes showing compassion towards Vader and other times being extremely hostile.
It could explore their relationship by showing the contrast between their current selves. Ahsoka is a free - thinking Jedi - like figure, while Vader is a servant of the Emperor. Their relationship could be one of enmity, with Ahsoka seeing Vader as a fallen hero and Vader seeing her as a nuisance to the Empire.