Naruto will pobably use sexy-no-jutsu and tobi will have a such a large nosebleed that the blood will fill his mask and force him to take it off.
Its supposed to be funny. Although it would be even funnier if it happened as he was summoning the juubi.ok ur post is silly... but if u are taking this seriously, i think it will be when he's attempting to summon the juubi
xD That would be the most humilating way of losing his mask.Nah Naruto is going to sneak up behind him tap him on his right shoulder
Go left, tobi looks right and naruto takes off his mask
classic way of doing things
How would he lose his mask? If he faceplants, then he will land on his mask.Tobi trips on a root and and falls. His masks comes off.