Saber (Fate/Grand Order - Muramasa)

Saber (セイバー) is a Saber-class Servant appearing in the Grand Orders of Fate/Grand Order.

Identity
Saber's True Name is, a Pseudo-Servant in the body of Shirou Emiya.

Muramasa is a famed blacksmith within. Legend says that he has forged a demon sword that antagonizes the. There were stories about his that killed Tokugawa Ieyasu's grandfather, there's also one that  used to commit suicide, and there’s also one that actually cut Ieyasu himself.

Muramasa claims that he is not qualified to be a Heroic Spirit because as a blacksmith, he lacks the heroic deeds necessary to make him a hero. It is for that reason he is manifested as a Pseudo-Servant in a suitable human body. It is unknown if he is a Heroic Spirit Candidate, Wraith, Phantom, or some other subset of spirit.

Muramasa theorize that he was summoned in Shirou because Shirou has a similar body and mind to that of Muramasa's. Furthermore he believes Shirou had shared his way of life and experienced a similar end. Muramasa speculates that Shirou could be his descendant.

Appearance
Because he is summoned in Shirou's body he looks exactly like him.

Personality
His personality is that of Muramasa, he speaks like an old man.

The ultimate sword he is aiming for is something that can purge the hate. A katana that cleaves through fate, destiny and karma. That can purge one's cause itself.

Shimosa Province: The Stage of Rivers of Blood and Mountains of Corpses
He was summoned by the Counter Force; a month or two in Shimosa before the arrival of Ritsuka Fujimaru and Miyamoto Musashi. He witnessed black ghosts attacking a paddy field during the day. Half of the farmers working on the field were killed, along with Onui & Tasuke's parents. Taking the children into his custody, he was given a hut from the west village. The hut used to belong to an old blacksmith, thus Muramasa was able to set up a workshop.

When Onui and Tasuke brought both Ritsuka and Musashi to her grandpa's house. The grandpa is Muramasa, who is called the Fearless Youth (精悍な青年), Ritsuka feels somewhat familiar to him, while Musashi was surprised to see him to be a little young and awes at his katana pieces. At first he is wary of the stranger until he learns both Onui & Tasuke was in the care of Musashi and Ritsuka. When Lancer Purgatrio arrives and attacks the group, Muramasa counters Lancer Purgatrio's attack and blows his upper body apart with his fake sword. However, Lancer Purgatrio regenerates, surprising Muramasa to see his attack is ineffective against the undead. When Ritsuka provides backup support for Musashi, Musashi borrows Muramasa's finest katana; though he warns Musashi of the danger of the sword. After Musashi wins her duel against Lancer Purgatrio, the group rest in Muramasa's hut. The next morning, Muramasa gifts the Katana to Musashi, calling it "Myoujingiri Muramasa" when asked by Musashi for its name. Muramasa then reveals himself to be Sengo Muramasa and a Servant. After having a meal with Ritsuka and Musahi, Muramasa takes them both to his workshop, where they discuss Muramasa's nature as a servant and the current paranormal activity.

He forges and uses Tsumugari Muramasa to destroy Amakusa's Onri Edo Castle.

Abilities
As a blacksmith, he is confident about his skills as he has reached the territory of God. He displayed Territory Creation skill as his whole workshop just never stops following him.

Saber is mentioned as being a swordsman skilled enough to cut even causality. Saber displays some battle abilities, he was able to dodge Lancer Purgatrio's spear and at the same time countered with his Blade-Testing Art, which blew Lancer's upper body half apart.

He crafted the blade Myoujingiri Muramasa (明神切村正), though he claims it to be a failure because he accidentally smithed it into a the realm of demon's and it became some sort of cursed sword. It's a literal double edged sword that'd cut both the victim and the user. It can cleave through the supernatural. It can cut through armor, boulders and even steel, but it is not something that a normal human can use. Musashi claims its whole structure and form made it feel much lighter than a feather when swung around and it has a whole new level of divinity within it. The katana is still imperfect as it can't really cut off anyone from fate or destiny but it can at least sever a cause.

He is able to forge the demonic sword Tsumugari Muramasa and use it, but using it will cause him to perish because he is not a god. Amakusa Shirou Tokisada, who witnessed the attack, mentions "that's the sword from the past when the gods ruled, the sword that came out of ." The demonic sword bisected both Reality Marble and the Onri Edo Castle. English= Not the invincible swordsman , neither the highly praised master of espionage , nor the renown Onmyouji Abe no Seimei. More than anything, just a swordsmith. But unpreparedness spelt your defeat.

Once seeking for the ultimate blade. A blade of steel cutting no flesh, nor bones and neither life. What I seek for is the clearance of resentment. The cutting of bonds, fate and destiny.

That is, to free oneself from Karma.

Upon ones arrival are countless tools. Carved over a thousand blades, forming a pile of swords. This is the place where all paths cross. This is the place where all desires flow. This is the place where all deaths await My whole life was for this single swing.

The heart of the blade is right here! Take this, This is my Tsumugari Muramasa!!! Japanese= 無敵の剣豪、十兵衛でもねえ、 隠密大名と誉れの高い半蔵でもねえ 噂のキャスター安部生命でもねえ なんでよりにもよって刀鍛冶のオレが呼ばれたのか そいつを計れなかったテメェの負けだ.

かつて求めた究極の一刀. 其は、肉を断ち骨を断ち命を断つ鋼の刃にあらず. 我が業が求めるのは怨恨の清算. 縁を切り定めを切り、業を切る.

―――即ち. 宿業からの解放なり.

・・・・・・其処に至るは多数の研鑽. 千の刀、万の刀を象り、築きに築いた刀塚. 此処に辿るはあらゆる収斂. 此処に示すはあらゆる宿願. 此処に積もるはあらゆる非業――― 我が人生の全ては、この一振りに至るために.

剣の鼓動、此処にあり―――！ 受けやがれ、こいつがオレの、都牟刈、村正だぁ―――！！！！ Romaji= Muteki no kengō,Jūbee demonē, Onmitsu daimyō to homare no takai Hanzō demo nē Uwasa no kyasutā Abe seimei demo nē Nande yori ni mo yotte katanakaji no ore ga yoba reta no ka Soitsu o hakarenakatta teme~e no makeda.

Katsute motometa kyūkyoku no ittō. 其 Wa, niku o tachi-kotsu o tachi inochi o tatsu hagane no ha ni arazu. Waga gō ga motomeru no wa enkon no seisan. En o kiri sadame o kiri,-gyō o kiru.

――― Sunawachi. Shukugō kara no kaihōnari.

......Sonotokoro ni itaru wa tasū no kensan. en no katana, man no katana o katadori, kizuki ni kizuita katana dzuka. Koko ni tadoru wa arayuru shūren. Koko ni shimesu wa arayuru shukugan. Koko ni tsumoru wa arayuru higō ――― Waga jinsei no subete wa, kono ichi furi ni itaru tame ni.

Ken no kodō, koko ni ari ―――! Uke ya gare, koitsu ga ore no, tsumugari,muramasa da ~a ―――!!!!

Development
Saber was first mentioned in Fate/Grand Order material I in EMIYA's's profile, EMIYA saying "...Hmph. Not bad..." His design was first shown on "Limited/Zero Over" craft essence.