"Thing You Should Protect" (守るべきもの, Mamorubeki Mono, Viz: That Which Ought to be Protected) is chapter 524 of the original Naruto manga.
Kakashi narrowly avoids Zabuza's attack. Zabuza and Haku are captured and restrained. Kitsuchi is informed of thousands of more Zetsu travelling underneath them. Mū, the Second Tsuchikage, is discovered by Gaara with his sand.