"How Come Until Now?" is chapter 600 of the original Naruto manga.
Summary
Kakashi and Guy are shocked,and start asking if he really was Obito.Seeing his Mangekyo Sharingan,Kakashi says it's no doubt about it.Kakashi gets flashbacks the time Obito dies,and asks if he really survived.Naruto asks Kakashi who Obito was,and Guy answers for him.Obito states that it didn't matter how he survived,saying that he blames Kakashi for letting Rin die.Kakashi,shocked by this,is unable to move.Obito says it's no time to be hasty,and tells Kakashi to stop making that face.Naruto states that it does'nt matter who he was,and tells Kakashi he"ll listen to the story later.Obito uses a fire technique,meant for Kakashi,with the full desire to kill him.Naruto blocks it with Kurama's tails.However,before the battle could end,Madara arrives on the battlefield.