wu_zetian_(fate)

Assassin-class Servant first seen in the Agartha (fate/grand order) chapter of Fate/Grand Order as the Assassin of Nightless City. The concubine of Emperor Taizong, but after his death, she married his son Gaozong and became Empress following a debilitating stroke that Gaozong suffered. She implemented the short-lived Zhou Dynasty in 690, interrupting the Tang Dynasty until it was abolished in 705 after her death.