-SENJUTSU-
After Jiraiya's death at the hands of Pain, Naruto began training with Fukasaku in Myōbokuzan to learn senjutsu and how to enter Sage Mode. In order to achieve this, Naruto had to learn to sense and control the natural energy around him. Once mastered, Naruto was able to perfect the Rasenshuriken, so that he could throw it, and learn Frog Kata, the taijutsu style that uses the natural energy around the user to enhance the range and the potency of their attacks. However, Naruto had one fatal flaw in his senjutsu training. To mold senjutsu chakra, the user must remain absolutely still. Something one can not do while in combat, and because of the Nine-Tails, Shima and Fukasaku are unable to fuse with Naruto to mold it for him. To counter this, Naruto has to leave two shadow clones in a safe place to mold the senjutsu chakra for him. Once he depletes his current amount of senjutsu chakra, he would dispel one of the clones and gather it's senjutsu chakra to reenter Sage Mode.