Elder Zhang Guo

Elder Zhang Guo or Zhang Guo Lao, Chang Kuo Lao in Wade-Giles, (張果老 in pinyin: zhang1 guo3 lao3) is one of the Eight Immortals. He is known as Master Comprehension-of-Profundity (通玄先生 tong1 zhao4 xian1 shen1).

He lived as an occultist-alchemist (方士) on Mount Tiao (條山) in Heng Prefecture (恒州 heng2 zhou1) during Tang Dynasty. By the time of Empress Wu, he claimed to be several hundred years old.

Empress Wu summoned him to leave the mountain, so he feigned death. He is the personification of a white bat. He rides a white donkey backward. Tang Emperor Xuan Zong (唐玄宗) attempted to give him an office with the title of Silvery Blue Guanglu Minister (銀青光祿大夫) ("guanglu minister" is a rank).