Mysterious Heroine X

Nickname:

Assassin, Heroine X, X

Assassin is an Assassin-class Servant able to be summoned by the Protagonist in the Grand Orders of Fate/Grand Order.
Assassin's True Name is Mysterious Heroine X, also known as Heroine X and just X, an unknown heroine who tasked herself in eliminating Saber-class heroines during Back Alley Satsuki - Chapter Heroine Sanctuary. Bearing the code name "A-X", X was a stranger who came from the "mysterious dimension" called the Servant Universe. Seeking to accomplish her "true, dearest wish" to "defeat all Sabers", she brandished Secretcalibur and left her home town, leaving behind an "expression full of bitterness." Even before arriving at Chaldea, she managed to save an ancient royal dynasty from a crisis, settle the internal strife of the "Mankind Integration Union", and rout invaders from another universe, but such actions were trivial enough for her to not even remember accomplishing them. She will continue to brandish her sword until her goal is completed, and can still be seen "dashing across the sea of stars" even today. No matter what, she also plans to cut down the "Golden Great Emperor Cosmo Gilgamesh."
X has revealed to none that her true identity is actually Artoria Pendragon. While she believes that her "perfect disguise" has tricked everyone, it is asked that others keep the fact quiet to keep from spoiling it and also for the sake of X's own honor.

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