Serious question for the Breaking Dawn sporkers over at Das-Sporking

So say Renesmee really is the Antichrist out to kill everyone. What makes you think Leah alone would be spared? Is there any qualification that Leah is more powerful than the other werewolves? If Renesmee kills the other werewolves she could probably just kill Leah as well. Seriously--I'm getting the impression that the only reason why you say that is because you actually like Leah.