Child of Light (光之子 “Guang Zhi Zi”) by Tang Jia San Shao
A Chinese fantasy webnovel by the author of Doulou Dalu, Kuang Shen and Shen Yin Wang Zuo. (Complete at 356 chapters)
The lazy Zhang Gong decides to learn light magic, a magic often ridiculed as useless for it’s defensive nature. However, he eventually becomes the legendary Grand Magister. While trying to end the continent’s east and west separation in order to unite all of the different races, he becomes every race’s Child of Light.