Board Thread:Naruto Discussions/@comment-24531362-20140904111518/@comment-1894786-20140905135748

Hadawu11 wrote: DBMalik wrote: And rinne tensei would also kill Sasuke.

I'm pretty sure it just uses a ton of chakra.

Nagato was deathly ill when he used it and it killed him. Obito was severely weakened when he used it and he died as well, until Naruto revived him. We've never seen it used by someone at full health and I think there's a reason for that. It may just be that the caster can only use it when they're on the verge of dying, or Kishimoto just wanted it that way for dramatic effect. The world may never know.