The young Chu Mu was plotted against and implanted with the White Nightmare by Xia Guanghan, and was taken to the Green Nightmare Island. Under the control of the Nightmare Palace, he and his soul pet Mo Xie were forced to fight bloody battles for survival, and eventually became the youngest king of the Prison Island. He became famous in front of the princess and was promoted to the Nightmare Master of Henghai. Chu Mu had some freedom and immediately returned to Gangluo City to save his family from danger. At the same time, Mo Xie's talent attracted Xia Guanghan's covetousness. Chu Mu fought again, and after a narrow victory, he was saved by his mother whom he had not seen for many years... (Source: Bilibili, translated)

Years ago, the gods fought against each other before being sealed away. However their artifacts remained in the souls of the HuaXia clan as part of a contract and hope that someday in the future, they will awaken once more using those artifacts. (Source: Baka-Updates Manga)

Sometime in the future, the world was completely dried up and became all desert. They had little rivers and lakes left, which villians and dangerous animals lived. Water has become the most valueable thing on the world. Whoever can control water will rule over the world. (Source: ANN)

Under the tutelage of the great demon warlock Romberg, Ike grew up with knowledge regarding an ancient advanced civilization that once ruled the land. Coupled with his innate talent in magical arts, this upbringing allows Ike to quickly rise in the Demon Lord's army ranks, leading his brigade to consecutive victories against humans. However, Ike has a secret—he is a human himself. Despite knowing all too well the consequences if this information is ever to leak, Ike is willing to face such immense danger to achieve his goal: find a way for humans and demons to coexist and stop the war that has been carried on for far too long.