The Ultimate Series was the short form of the fantasy novel," The Ultimate Series ", created by the author, Xiao Ding. The series consisted of the Ultimate Series: Skyfire Avenue, Ultimate Series: Sword Qi Western Liang, and Ultimate Series: Shadow Wheel, totaling 20 novels. The series used modern China as the background to tell the story of the protagonist, Xiao Yan, who traveled to ancient times and started a series of thrilling stories with various characters. The most famous novels in the Ultimate series were the Ultimate Ancient Emperor of Fire, the Ultimate Ancient Emperor's Inheritance, and the Ultimate Ancient Emperor's Text. Ultimate Doujinshi refers to the continuation or adaptation of the ultimate series of novels, usually based on works by different authors or from different cultural backgrounds. These doujinshi works sometimes added new elements or plots or re-created and arranged the characters in the novel. For example, on the basis of the Ultimate Series of novels, there was an author who created a doujinshi work called "The Ultimate Inheritance of the Ancient Emperor", which described the story of Xiao Yan traveling to ancient times to explore the inheritance of the Ancient Emperor with the main character. In addition, some authors had adapted the Doujinshi works of " The Ultimate Ancient Emperor's Legacy " and " The Ultimate Ancient Emperor's Legacy " and added new elements or plots, such as " The Ultimate Ancient Emperor's Treasure " and " The Ultimate Ancient Emperor's Legend ".