Depending on the results, it'll change a lot of the story. Should I keep Vegeta and Nappa alive? If I do, they'll still have important roles in the story, but at the same time, I could go without them. (Here's a little hint: if they are alive, every Saiyan will go down their own path, but there may be fewer opportunities to show off their might in actual battle.)
Comment for each option:
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-Kill Vegeta and Nappa
-Keep Vegeta and Nappa alive