Who was the most outstanding calligrapher in Song Dynasty in China?

Cai Xiang, Mo Jun, was born in Xianyou County of Xinghua Army (now Qingze Pavilion in Fengting Town). Famous calligrapher, politician and tea scientist in Northern Song Dynasty. Song Renzong Tiansheng was a scholar in the eighth year, and successively served as a collator of Guange, an admonition institute, a history museum, an intellectual patent, a bachelor of Longtuge, a bachelor of Privy Council, a bachelor of Hanlin, a three-emissary, and a bachelor of Duanmingtang. He also served as a traffic envoy in Fujian Road and learned about Quanzhou, Fuzhou, Kaifeng and Hangzhou. Cai Xiang's calligraphy is good at poetry. Its calligraphy is vigorous and dignified, simple and beautiful, and it is one of the "Song Sijia". There is The Complete Works of Cai Zhonghui Gong.

Su Shi, whose word is Zi Zhan, whose word is Zhong Zhong, and whose name is Dongpo lay man, is a Taoist, and the world calls him Su Xian. An important litterateur in the Song Dynasty, a representative of the highest literary achievements in the Song Dynasty. Han nationality, a native of Meishan, Meizhou (now Meishan City, Sichuan Province) in the Northern Song Dynasty. Song Renzong was a scholar during the reign of Jiayou. His poems have a wide range of themes, fresh and vigorous, good at exaggeration and metaphor, and unique style. He and Huang Tingjian are also called "Su Huang". Xin Qiji is the representative of the unconstrained style, also known as "Su Xin". He is also engaged in painting and calligraphy. There are Seven Episodes of Dongpo, Dongpo Yi Zhuan, Dongpo Yuefu and so on.