Board Thread:Naruto Discussions/@comment-1872728-20180201032503/@comment-734582-20180210121605

Georgio722 wrote: Ah okay. But yeah thinking back, Obito should've died like 5 times: I think he was saved by Zetsu. I mean, this is never explicitly said, but we know Madara was waiting for a pawn and the Zetsu were spying and can move through the earth. Seems to me it's virtually guaranteed that a Zetsu encased and saved him.
 * When he was smashed by the rock. (Saved by Madara's tunnel)

Georgio722 wrote: (Died for real, but still managed to come back as a spirit) He has the ability to synchronize with a different space-time (which makes sense: he takes his own Kamui dimension with him, so the only way to return to this world is by "marking" it). The afterlife/Limbo are just another space-time, and so he simply returned to a previously-marked dimension. Of course Spirits are extremely limited in what they can do in our world (as they have no substance), but since Obito knew how Edo Tensei worked he could simply apply the principles and empower Kakashi.