"Naruto's School of Revenge" (ナルト、仇討ち指南塾, Naruto, Adauchi Shinanjuku) is episode 181 of the Naruto: Shippūden anime.
During the construction of Konoha, Naruto, Sakura, Inari, and Tazuna sit together remembering the days of the original Team 7. The team was on a mission of having to return Mr. Ostrich to his habitat. When travelling through what it seemed like a small city, they encountered a challenger Tsukado fighting for the revenge of the deceased family member. Naruto unsuccessfully trained Tsukado but after Mr. Ostrich went wild, Tsukado revealed his sword skills, explaining that he cannot win since he cannot look straight into Kageki's eyes. Meanwhile, Kanabun's gang organised the fight once more, and Tsukado lost again for the same reason. Naruto, seeing something is not right interrupted the fight and discovered that Kageki is not the man Tsukado's looking for, explaining that Katazu took the role of his brother since the murder was an accident, thus Tsukado cancelling his vendetta. Team 7, Tsukado, Katazu, and Mr. Ostrich managed to gain victory after chasing the gang out of town.