Wu Zetian is a Servant in the Fate series, specifically referenced in Fate/Grand Order contexts. She is the historical Empress of China, known for her role as mother-in-law to Yang Guifei. In the series, she interacts with other Servants like Van Gogh, borrowing her aura for abilities named after 'Starry Night' (星月夜 or 星夜). She appears in events involving imaginary space and Noble Phantasms, showcasing her influence in battles and singularities. Listed among Berserkers and other classes in Traum Singularity factions.