Manhuajia Shengcun Zhinan

A Xue, an unsuccessful artist whose manhua was about to be axed, transmigrated into the world of his own manhua by chance. In his comic, the Pandora Continent was on the verge of destruction due to the growing power of the Demon Lord, which put A Xue in danger as well. Facing imminent doom, A Xue was given a second chance at survival, with the condition that he takes over the hero’s role from the beginning and redo the entire story. If he fails to "create" a more interesting story-line, then A Xue and the entire world will be destroyed…

(Source: Kuaikan, translated)