Planetary Devastation (地爆天星, Chibaku Tensei) is episode 167 of the Naruto: Shippūden anime.
After Hinata is taken down by Pain, Naruto becomes enraged, which causes the release of the Nine-Tails' chakra. He then changes into his four-tailed form and attacks Pain. Sakura feels the presence of the Nine-Tails' chakra and she recalls the battle on Tenchi Bridge. Pain's fleeing and continuous preachings anger Naruto more. He eventually progresses in his transformation to a six-tailed form and bombards Pain in a flurry of enhanced attacks. In the middle of their battle, the First Hokage's Necklace activates and tries to seal away the Nine-Tails' chakra. However, the Nine-Tails is able to over come the sealing process and destroys the necklace before continuing its attack. They resume their fight, with even Pain's Shinra Tensei being ineffective against Naruto. Naruto launches a Tailed Beast Ball, although Pain slightly disrupted it, and it creates a vast explosion. Sakura wonders why the seal is not working, and Katsuyu informs her about what had happened. Pain retreats in order to perform Chibaku Tensei. The technique rips apart the ground creating a small moon and traps Naruto inside of it. On a mission elsewhere, Yamato senses Naruto has broken the seal and aborts his mission to track Kabuto, to return to Konoha. Within his sub-conscience, a traumatised Naruto begins a mental breakdown and grows angry at his inability to answer Pain's question on how he will achieve peace. This causes to Naruto soon enter his eight-tailed form but cannot break out completely. He succumbs to the Nine-Tails' will and resolves to crush all that brings him suffering. Approaching the seal the restrained the Nine-Tails, Naruto is stopped by the Fourth Hokage who suddenly appears, snapping Naruto out of the breakdown and seeming to somehow know his name.