This article may contain Spoilers So Beware
Naruto Shippuden Episode 343 Who Are You? Naruto enter his tailed beast mode and attacks Tobi. Meanwhile, kakashi is being hesistant about who the masked man who pretended to be Madara is guy makes him snap out of it.He is then motivated to fight. Tobi unleashes a bunch of chakra receivers that paralyses b and 8-tails. Naruto creates a shadow clone and charges forward with a rasengan while the real Naruto prepare a tailed beast bomb. As naruto launches his technique Tobi slips to the other dimension when he see the clone attacking him with the rasengan. With little time to react  tobi's mask is hit by the rasengan therefore shattering his mask to pieces. Being back to his own world guy and kakashi are shocked to see that the masked man is their old comrade is obito and Kakashi being shocked about how obito survived. With Naruto wandering who Tobi is, Guy respond that was their old comrade Obito who they taught died in the previous war. Obito respond to Kakashi's question about why he hasn't shown himself to the village if he was alive he says it's because Kakashi let rin die. Naruto motivates a devastated Kakashi as obito's plan to use the infinite tsukuyomi needs to  be stopped. He then attacks them with his Fire Release: Blast Wave Wild Dance Jutsu but Naruto stops it with Kurama's tailbeast cloak's tails. Just then, Madara appears next to obito surprising everyone who was there.Source IT correspond with the mangas chapter 598,599,600 and takes place during the Ten-Tails Revival Arc and was release in Japan on December 19 http://naruto.wikia.com/wiki/Who_Are_You%3F