Tobi because nobody could defeat him. But i think if naruto fight Tobi Tobi will get kill
Probably Itachi. no, only one possible is tobi.
naruto 99
NARUTO... duhhh!
Naruto wants to fight Tobi, and A fears that Tobi will extract the fox from Naruto and use it to take over the world
Tobi is actually Uchiha Madara.
Tobi is really Madara Uchiha
Before Naruto could master Sage Mode, JIraiya was stronger than Naruto. Now that Naruto mastered Sage Mode and controlled Kurama, he is now stronger than Jiraiya.
Yes. Because orochimaru was weaker than sasake and naruto is stronger than sasuke.
Naruto is indeed stronger than sasuke
The 4th hokage was strong but Tobi is stronger then the 4th
Naruto is stronger than gaara in naruto shipudden.