"Nadeko Medusa, Part 4" (なでこメドゥーサ 其ノ肆, Nadeko Medusa Sono Yon) is the fifteenth episode of Monogatari Series Second Season and the last episode that adapts the Nadeko Medusa arc in Otorimonogatari. It was broadcast on October 12, 2013. Nadeko Sengoku reaches breaking point and becomes a snake god before Shinobu Oshino and Koyomi Araragi. In this powerful form, Nadeko looks back at the real events behind her "adventure" with Kuchinawa.