Quote Originally Posted by Eonaite View Post
Didn't Tobi use Izanagi during his fight with Konan?
He did and if my memory serves me correctly, he used it for an extended period of time (more than a few minutes) while Konan's paper bombs kept exploding.

So I've narrowed the possibilities down to Tobi must be of Uchiha bloodline, or powered by Senju Yang energy (and a shit ton of it because he never deactivates the Sharingan)