"Big Adventure! The Quest for the Fourth Hokage's Legacy Part 2" (大冒険! 四代目の遺産を探せ・後編, Daigōken! Yondaime no Isan wo Sagase Kōhen) is episode 171 of the Naruto: Shippūden anime.
Naruto, Sakura, and Team 10 take on the oncoming challenges in order to find the secret technique and break the previous record set by the Fourth Hokage, but Naruto's impulsive action leads the group into various troubles. While Naruto and his friends search for the former Hokage's legacy in the temple, the fifteen shinobi of Amegakure come up from behind and use Grudge Rain ain an attempt to take them out, flooding them inside. In order to practise using Chidori on moving targets, Kakashi sends Sasuke to the temple, where he proceeds to use it on the Ame-nin.
Naruto and the others find the scroll, only for it to read "there are no shortcuts to becoming to a ninja". The others realise that Guy set the whole thing up to hone their skills and reflect how they began the day with individual goals whilst ending it with the hope that at least a Konohashinobi passes the exams; Naruto, however, decides that the scroll's true meaning is to partake in the entire obstacle course once more, but to take the longer route.
There are plot holes in this episode:
Chōji is seen participating in the hunt for the Fourth Hokage's legacy, which takes place the day before the final rounds. However, at that time he was hospitalised due to indigestion, and was not discharged until right before Shikamaru's match. Additionally, Naruto, Shikamaru, Ino and Guy are involved in the quest as well, even though the day before the final rounds, Ino was at the hospital with Chōji while Shikamaru and Naruto encountered Gaara trying to kill Lee, who was saved by the arrival of Guy.
Kakashi tells Sasuke not to use Chidori in the next day's match; however, during Sasuke's match against Gaara, Kakashi reveals that the entire strategy was to use taijutsu to inflict damage on Gaara while building up his speed required to use the Chidori.