I say Izanagi. Even if it's for a short period, if you're like Danzo or Madara (he has a whole storage of Sharingan so he can do it all day), nothing will work on you. Someone could use Ama and burn you till your half a skeloton or looking like two face from Batman and Susanoo can shoot you with a thousand arrows, and crush you and you just make it seem like it was all a dream (that would be a hell of a nightmare I would assume) but you'll come out unharmed.