1. Why did Obito join the Akatsuki as Tobi?
2. Does Obito pretend to be Tobi?
3. Why did Tobi stop pretending?
4. Did the Akatsuki know Tobi was Obito?

Why did Obito join the Akatsuki as Tobi?

After the Uchiha Massacre Itachi was considered a rogue ninja, Obito knew what Itachi was capable of and decided to invite him to the Akatsuki because he believes it would’ve been a waste not having him in the organization. Shortly after Kisame murdered a feudal lord and thus was considered a rogue ninja.

Does Obito pretend to be Tobi?

Obito is the true form of Tobi and the most serious and threatening among the Akatsuki members. Tobi is a member of the Akatsuki and Madara’s spawn. His purpose is to inform other Akatsuki members about a death related to them. Madara is also the name Tobi used before revealing his true self.

Why did Tobi stop pretending?

The facade of Tobi was over, so there was no reason to pretend to be a dunce, or weaker than he actually was. Obito didn’t like acting like a dofus all the time. It was a thing he did only to hide his identity from people. When you have no need to hide your identity than you don’t need to act like someone else.

Did the Akatsuki know Tobi was Obito?

No one knew he was Obito except for Black Zetsu and White Zetsu. Nagato, Konan, and Itachi knew him as Madara, though they may have been skeptical of this claim.