The Sunflower Manual (simplified: 葵花宝典, traditional: 葵花寶典, pinyin: Kuíhuā Bǎodiǎn, jyutping: kwai4 faa1 bou2 dim2) was a martial arts treatise in Laughing in the Wind created by a palace eunuch of a previous dynasty. It contained techniques of transcendent power but required self-castration to master: “If you want to practice this technique, you must first castrate yourself” (欲练此功，必先自宫).
Overview
The manual emphasised supernatural speed, enabling practitioners to strike before opponents could react. Dongfang Bubai mastered it and became the most powerful martial artist in the jianghu, though the transformation also changed his psychology and appearance.
Yue Su and Cai Zifeng of the Huashan School secretly copied the manual from Putian Shaolin Temple. The monk Duyuan (later Lin Yuantu) was sent to investigate, memorised its contents, and created the Evil-Warding Swordplay based on it.
Ren Woxing deliberately gave Dongfang Bubai the incomplete manual, knowing self-castration would neutralise him as a threat. The plan backfired when Dongfang Bubai mastered the technique and usurped Ren Woxing.