Talk:One Technique

Tobi, it seems, is also a 'Kamui' user - only his is on an entirely new level. While Kakashi has yet to return something from the 'other side', Tobi does this with relative ease.

I think I understand that when Kakashi 'bamfed' Naruto's rasengan a foot away from Tobi, Tobi unknowingly walked into the 'trap' when he got to the point where the rasengan was and rematerialized himself - thus both his right arm and the rasengan were bamfed back at the same point - and thus the kaboom.

Now as for the kunai - note that Tobi was moving towards Naruto even as the kunai got 'bamfed'. His mask got right at the position where that kunai disappeared - or not. I can't explain the kunai and the crack on Tobi's mask it seems.