Sai and Shin

is episode 263 of the Naruto: Shippūden anime.

Summary
Upon seeing his old puppet body, Sasori mused that he no longer required it as he had an immortal body that he had always desired now. As the battle between the two divisions got under-way, Shin was sent in to battle Kankurō's Sasori puppet. Omoi also joined the fray having been informed by Hoheto Hyūga that Shin's stomach was full of explosive clay and that Lightning Release was able to counter it. Omoi's attack missed, however, and Deidara detonated Shin. The explosion was stifled by Kankurō's puppet, Sanshōuo, which encased Shin. Enraged by Deidara's reference to his brother as a bomb, Sai created a replica of the Benevolent Kings who knocked Deidara and Sasori out of the air and into Kankurō's awaiting puppets. As Deidara tried to blow himself up, Omoi channeled his lightning-imbued sword into the mouth on his chest before Deidara was immobilised by the Sasori puppet's coil of wire. Shin saw the drawing of both him and Sai holding hands which freed his soul. Kankurō's speech to Sasori moves him despite Deidara's warning not to listen to them. Entrusting Kankurō with his Mother and Father puppets, Sasori asked Kankurō to pass them down to the generations to come, to which Kankurō agreed. Seeing Shin's and Sasori's bodies crumbling into ash and the bodies beneath them, the Surprise Attack Division realise that sacrifices were needed for the technique. Elsewhere Kabuto Yakushi told Tobi to head out the battlefield while he focused on the Summoning: Impure World Reincarnation. Tobi deduced that Kabuto was using him and the Allied Shinobi Forces to take each other out, but promised he was the one using Kabuto.

Trivia

 * In the English dubbed version of this episode, during Shin's fight against Sai as well as during the flashbacks, he calls the latter by his current codename, even though Sai was never given said codename prior to Shin's death, thus Shin shouldn't have known this.

Credits
Sai y Shin Sai i Shin