"Mifune vs. Hanzō, the Conclusion!!" (ミフネVS半蔵、決着!!, Mifune Bāsasu Hanzō, Ketchaku!!, Viz: Mifune vs. Hanzo, Decided!!) is chapter 532 of the original Naruto manga.
Mifune reminds Hanzō of what Hanzō had told him during their prior fight as Mifune lay there dying from the poison he received from Hanzō's kusarigama strike. As Mifune laid there dying, Hanzō appreciated his bravery and gave him an antidote for the poison. Reminded of his prior life and in a tremendous demonstration of will, Hanzō places his faith in Mifune and overcoming the talisman that governs him, he commits "seppuku" (切腹, Literally meaning: stomach-cutting) with his broken kusarigama. Piercing the internal venom gland located within his body in the process, an enormous poisonous cloud is released that paralyses the entirety of Hanzō's movements, creating an opening for the Fifth Division to exploit in order to seal him away for the remainder of the war.
In the battle between Asuma and his former students, Shikamaru was able to use his Shadow Imitation Technique to herd Asuma close enough to Chōji for him to strike. But as Chōji uses his Partial Multi-Size Technique on his arm to strike at Asuma, he holds back and stops. This gives Asuma the chance to strike Chōji and prepare to use Wind Release: Dust Cloud Technique, warning his students to run away.