It could be a genetic mutation in the fanfic's storyline. Some strange event or factor could have caused a change in Bardock's genes, making it possible for him to become Super Saiyan. This genetic change might be related to some ancient Saiyan lore or a new element introduced in the fanfic's universe.
The change of Bardock becoming Super Saiyan in the Vegeta fanfic can completely rewrite Saiyan history. It could start a new era of Saiyan pride and power. Bardock, with his new - found Super Saiyan form, might be able to teach the younger Saiyans about the transformation. This could lead to a more united Saiyan race, as they all work towards achieving the Super Saiyan state. It might also mean that they are not as easily defeated by Frieza, as they have a stronger force to oppose him. This could result in a different galactic power structure, with the Saiyans being a more dominant force.
Another theme could be loyalty. Bardock might be loyal to the true potential of the Saiyan race while King Vegeta is loyal to the existing power structure. This difference in loyalty can create a great conflict in the fanfic. Also, there could be a theme of social change. As Bardock may represent the underclass Saiyans who want a change, and King Vegeta is the symbol of the old regime.
The Saiyan race would likely face more destruction and chaos. Without Bardock saving Vegeta, the leadership of the Saiyans might be in disarray. The power structure could crumble as Vegeta was an important figure. Enemies of the Saiyans could take advantage of this situation and launch more attacks. It could also lead to a loss of hope among the remaining Saiyans as one of their strongest leaders is gone.
The fanfic 'Bardock: The Super Saiyan God's Redemption' is quite good. In it, Bardock, as a Super Saiyan God, has to atone for the past sins of the Saiyan race. He travels across the universe, helping those who were once oppressed by the Saiyans. It has an interesting take on Bardock's character as he tries to rewrite the Saiyan legacy through his actions as a Super Saiyan God.
Bardock's power as Super Saiyan in the manga is depicted as extremely high, allowing him to take on formidable foes.
A 'bardock vs king vegeta fanfic' could explore the backstories of both characters. Bardock's story as a Saiyan who starts to question the Frieza regime might contrast with King Vegeta's more traditional and perhaps self - serving rule. Their fight could be a symbol of the changing tides within the Saiyan community. It could also introduce new elements to the Dragon Ball lore, like different forms of Saiyan power that are unique to this fictional encounter.
Super Saiyan Vegeta's dimensions aren't clearly defined in the manga. It's the intensity of his fights and his evolution as a character that takes center stage.
Definitely. Fanfiction is all about creativity and bending the rules. Since the super saiyan concept comes from Dragon Ball and Harry Potter is from a different fictional world, in fanfic, these two can be mashed up. Writers can come up with all kinds of explanations for how Harry Potter gets the super saiyan transformation, like some kind of magical - energy - dragon - ball - type of thing.
There's a fanfic where Bardock becomes a Super Saiyan God in an alternate universe. Here, he uses this power to try and change the fate of the Saiyans. The story could show how his newfound power affects his relationships with other characters like Vegeta and Goku, and how he might use it to stand up against the likes of Frieza in a different way than in the original story.
Yes, there might be some out there. You can start by checking popular fanfiction websites like FanFiction.net or Archive of Our Own. Just search for 'bardock x king vegeta' on their search bars and you'll be presented with various fanfics related to this pairing.