Kakashi, Sasake, Sakura or Kakashi, Sakura, Garra
I assume you mean just kill all important characters not just kill everybody on the whole verse.
Not a sasake fanboy. My first choose is if everybody dies in my opinion naruto should die either way it would be more emotional than Sasake dying. If just important characters die than def Kakashi, Sakura, and maybe Lee. Kakashi because it would add a more dynamic deeper emotion from him since he has outlived most his closest allies humbling him further making him prime candidate for leadership. Sakura because she would get a reality check losing both the comrades she loved forcing her to become stronger and a better woman for that matter( love Sakura btw kishi doesn't do her character justice character wise potentially) and idk someone like Lee to carry on Youth and the definition or determination and willpower.
