I doupt it would be game over... U_U Don't forget it's an MS/rinnengan user we are talking about... U_UWhen Naruto Rasengan'd Tobi in the other dimension, why didn't he shot him in the heart/chest. It would've been game over. & they still would've unmasked him.
But its hard, its custom made for war. Naruto should've at. Least hit him on his back head.Well, the head is "game over" aswell (brain inside)
Cause he has no rock hard mask, taking 95% of the damage .He didn't die after taking a rasengan to the face, why would he have been killed after taking one to the chest area '>_>