Search for Tsunade, Vols. 16–19

With Konoha leaderless, Jiraiya is picked, turns it down and sets out with Naruto to find Tsunade, the other Sannin. On the way, the Akatsuki's Itachi and Kisame come for Naruto, and Sasuke, rushing to face his brother, is humiliated and left in a coma. Jiraiya teaches Naruto the Rasengan, and Naruto bets Tsunade he'll master it in a week. Orochimaru wants Tsunade too: he offers to bring back her lost loved ones if she heals his arms. She refuses, and the three Sannin clash with toads, slugs and snakes. Naruto lands the Rasengan on Kabuto, and Tsunade returns to Konoha as Fifth Hokage and heals Sasuke and Rock Lee.

1. ReferenceTsunade and the slugs

   In the folktale Jiraiya Gōketsu Monogatari, Tsunade is Jiraiya's wife and learns slug magic, which beats snake magic. Hence her slugs against Orochimaru's snakes.

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2. Behind the scenesItachi had no backstory yet

   When Sasuke first mentioned Itachi, Kishimoto hadn't worked out his story. All he knew was that Itachi had done something terrible enough to make Sasuke want revenge.

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3. ReferenceThe first duel

   Sasuke and Itachi's first clash is in chapters 147–148, in volume 17, which VIZ titled Itachi's Power.

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4. ReferenceOn screen

   The arc became episodes 81–100 of the first anime.

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