Honestly, I don't know why we would scale 1% Urek to Karaka's durability, as the rapper was using his index finger, which still nearly one-shot Karaka and obliterated half of his body, and the only reason Karaka survived was his regeneration and stamina, and how
@ImNot4nUser said, Urek's finger attack was something more concentrated than a beam like Rose Shower and the fact that Karaka wasn't completely destroyed was more due to the fact the small Area of Effect from the Mr. Finger's attack than anything else, if Urek had used a punch the story would have been different, and even Karaka himself said that there's now way he can defeat even a single one of 1% Urek's fingers