Late-Southern-Sòng nèidān 內丹 author of the Southern Lineage (Nánzōng 南宗), zì Yuánruì 元瑞 (also Tiānruì 天瑞), hào Zǐxū liǎozhēnzǐ 紫虛了眞子 (“Master of the Purple Void who has Realised the Truth”). A native of Fúzhōu 福州 (Fújiàn). Disciple of Péng Sì 彭耜 (one of Bái Yùchán’s most prominent followers); the discipleship is attested in Xiāo’s preface (dated 1260) to [[KR5c0687|DZ 687 Dàodé zhēnjīng sānjiě]] (preface, 8a). For the second zì Tiānlái 天賴, see Quán Sòng cí 全宋詞 4.2777. Author of [[KR5a0265|Jīndān dàchéng jí 金丹大成集]] (DZ 263.9–13 = the present work in the Kanripo split), a five-juan compendium that became a standard later anthology of Nánzōng nèidān terminology and method. Xiāo is repeatedly quoted in [[KR5c1005|DZ 1005 Zhōuyì cāntóng qì fāhuī]] (e.g., 3.3b, 5.18b, 6.2b), and his commentary on the Cuīgōng rǔyào jīng 崔公入藥鏡 is preserved in [[KR5c0135|DZ 135 Cuīgōng rǔyào jīng zhùjiě]]. He also wrote a commentary on Lǚ Dòngbīn’s 呂洞賓 cí-lyric Qìnyuánchūn 沁園春 (cf. DZ 136). Some of his cí are reproduced without attribution in [[KR5c1100|DZ 1100 Mínghè yúyīn 鳴鶴餘音]] (1347). The Dàozàng jíyào 道藏輯要 edition of his Jīndān dàchéng is incomplete. No CBDB record found; the floruit follows the catalog meta and Baldrian-Hussein’s standard scholarly notice.