Caster (キャスター, Kyasutā?) is a Caster-class Servant able to be summoned by Ritsuka Fujimaru in the Grand Orders of Fate/Grand Order. He takes up the position of Grand Caster (グランドキャスター, Gurando Kyasutā?) after Solomon utilizes Ars Nova.



Caster's True Name is Merlin, the Magus of Flowers (花の魔術師, Hana no Majutsu-shi?). The vagrant of the paradise. The court mage, advisor and prophet that appears in Arthurian legends. He would at times guide, at times torment and at times help King Arthur so that she could overcome many enemies and hardships. Still, even as a wise man he is fundamentally inhuman. For you see, he is a mixed-blood of incubus and human.[2] His mother was a princess of Wales, but his father was supposedly a supernatural incubus that lived between the Earth and the moon.[2][3]

It has been said that he performed many prophecies at a young age. Among those, the prophecy that caused Merlin’s name to become widely known was one in which, after correctly guessing about the existence of a red and a white dragon sleeping beneath Mt. Emrys, he spoke how those red and white dragons would fight against each other upon waking up. Merlin's words, which were transmitted to posterity as prophecies, indicated the red dragon as Britain and the white dragon as the Saxons and that Britain would gather their forces under a great king and surely reign over Gaul and Rome. He also left behind many other prophecies, among which there were those concerning wars and even the king's death.[2]

He served King Uther Pendragon.[4] Uther loved Igraine, the wife of Duke Cornwall, so he secured Merlin's assistance in winning her love at the price of leaving his child in Merlin's care.[5] Merlin arranged the marriage between Uther and Igraine, watch over King Arthur's since before her birth.[2] Merlin told Uther a prophecy about his child, who would become his appointed successor during their war-torn times.[6] Under an arrangement from Uther, he helped produce an heir bearing the "essence of a dragon", so Artoria was born as a human infused with a dragon's magical energy.[7] Although the child was a girl who could not officially become the successor, Merlin was delighted all the same, believing that her sex never mattered. Confident that her being separated from the castle until the prophecy was fulfilled was proof that she would become king, he entrusted her to the king's vassal, Sir Ector, and had her raised as the child of a knight. Merlin visited at some point and swore Sir Kay to secrecy about the matter of her gender.[8] According to anecdotes, he taught many things to the young Arthur and ascertain her growth as if a foster father-like existence.[2]

He prepared Caliburn for the selection of the next king, but none could pull it out of the stone. As the other participants prepared a jousting match to decide the kingship, Artoria neared the sword and prepared to pull it without hesitation. Merlin appeared before her then, telling her she should think it through and describing that to become "king" is to no longer be "human." Warning her that she should stop because she is fated to die a miserable death while resented by all humanity, he showed her the end she would face.[9] Having prepared for that day since her birth and firmly believing in the people smiling she saw in Merlin's vision, she pulled it without hesitation and became king.[6][9] As he left her, he said that in exchange for the miracle that she will lose that which is most important to her.[9]

Due to Artoria having issues with discussing her gender and producing an heir, his magecraft was to solve it by making her a pseudo-male for an unknown duration of time, which allowed for the creation of Mordred from her sperm.[7] Artoria lost Caliburn at a later point and obtained Excalibur and Avalon from the Lady of the Lake. It is said in legend that he asked Artoria about which implement was better, chiding her for choosing the sword because the sheath will protect her.[4]

Merlin has left King Arthur before the last battle with Mordred due to his love affairs problem. He claims that the cold-mannered woman has been trying to murder him so he has taken refuge to the Reverse Side of the World where he'd crossed the boundary and stumbled into a foreign land known as Avalon.[2][3] Merlin had thought that the evil witch could not reach him anymore. But he encountered a gate that was built with rough stones, resembling the stone circles. The gate was inscribed with "Only the innocent may pass". Merlin realized that the gate was a trap and he was imprisoned when he had walked into it. Massive walls of stone emerged from the ground in front of him. The walls seem to vertically extend forever, effectively trapping the visiting magus inside. The place is like a tower without a roof.[3]

Merlin is fated to be trapped in this prison “tower”, called the Garden of Avalon, for eternity, having transcended death. To ascertain the world of humans until the end of the universe, without being able to die. As if to say that this is the fate of a foolish man, who playfully meddled with the fate of a single girl.[2] This also means that there is no possibility of him becoming a Heroic Spirit even if he is worshiped by the masses, since he is unable to die in order to have his soul recorded in the Throne of Heroes.


Merlin wears a robe woven with the finest fabrics, though he still looks modest, his long hair appearing in colours of the rainbow under sunlight.[3]


“I like the world of humans very much, but when it comes to each of them individually, I’m relatively, look, well, yeah! Very well, I suddenly feel that some things are better left unsaid!”


A young man who is like a wind blowing on grasslands. Before him, anyone end up letting the tension out of their shoulders - a refreshingly righteous person. Still, due to seemingly be quite lacking in terms of seriousness and sense of responsibility, he may also appear as a shady con man. A rhetorician who, even while perceiving things in an objective manner and accepting the cruelty of the world of humans, turns it into something bright by saying things like: “But, it wouldn’t be fun otherwise, right?”[2]

Despite being a hybrid being, Merlin has never hated humans. Rather, he is fond of them to such a degree that it is beyond natural.[3] He loves the world of humans, loves mischief and loves girls. The magus of flowers who retorts at most things with a refreshing smile and a calming expression such as “now, now”.[2]

He tends to appear as having a perfectly happy personality without a single worry, but since Merlin himself is self-aware about the fact he is foreign body in regards to human society, he never crosses that last step; the wall also called friendship. Ultimately, he is always watching over the world so that mankind reach a happy outcome.[2]

He is very boastful about his abilities as a Mage, claiming that he inflicts jealousy and envy on all other servants, especially Casters, since they are second-rate to him.


Artoria Pendragon
Knights of the Round Table


Fate/stay nightEdit

In Fate route, Merlin was mentioned when Shirou Emiya was dreaming about Saber's past.[6][9][10] Rin Tohsaka briefly mentions Merlin when they discuss about King Arthur legend.[4]

In the Unlimited Blade Works route, Saber describes him as being still active in present tense even when she is summoned as a Servant. Saber reveals that she shares a common trait with Shirou as they were fond of an immature magus. Saber describes Merlin to Shirou, he has the bearing of someone unlike a magus, much to the point where it would be hard to believe him when he claimed to be one. Noted to be a "troublesome adult", he is spaced out and clumsy, freely enjoying his pastimes and playing around like a child. More immature than Artoria, he was somebody she "couldn't leave alone", but she respected him greatly as a magus. Despite that, she describes him as the cause of every trouble and mentions that the age would have been better off had he been less mischievous. Agreeing with Shirou that he could be described as a "real bad guy", she describes his worst trait as being "weak against love affairs", or more aptly "full of love." Although it led to his downfall, she believes he is "still casually talking about love."[11]

In the Last Episode, Merlin explains to Saber that her dream to reunite Shirou is difficult and near impossible. He informs Saber that two miracles must occur, in order for them to meet again as normal people. One must wait continuously, while the other must pursue endlessly. They must realize that it is impossible to succeed yet at the same time be capable of enduring patiently.[12]

Garden of AvalonEdit


Merlin trapped in Garden of Avalon.

Half of the story is narrated by Merlin as he was imprisoned in the stone tower.[3]

While the other half resembles conversation between Merlin and various Knights of the Round Table. The story tells the Fate version of King Arthur's legend from the day she pulls out Caliburn to her demise.

After Merlin witnesses Saber's last moments in the Fifth Holy Grail War, he is pleased with the outcome. He releases Cath Palug from the Garden of Avalon in the Reverse Side of the World. He insists Cath Palug to seek freedom and to play into something really beautiful.[13]

Fate/Grand OrderEdit

E Pluribus Unum: Grand Battle of Legends in North AmericaEdit

Merlin makes a brief appearance during the Grand Order in America, wandering through as Cu Chulainn (Alter) prepares to destroy the Protagonist. Remarking that he cannot truly intervene due to daydreaming, he declares that he shall meet the Protagonist properly at the designated future, and requests they take care of his Familiar, Cath Palug, for him.

Babylonia: The Absolute Frontline in the War Against the Demonic BeastsEdit

Utilizing Independent Manifestation, he arranged for Gilgamesh to summon him as an enfleshed, Caster-class Servant, supporting Uruk in the war against the Three Goddess Alliance and Tiamat. However, a part of his existence was actually insinuated within the dreams of Tiamat, holding her in a state of slumber. When Tiamat's avatar, the Conglomerate Divinity Gorgon, was defeated, the awakening Tiamat destroyed Merlin's Servant iteration. Subsequently, he temporarily escaped Avalon, appearing in Babylonia during the final confrontation with Tiamat neutralize the Divine Authority of the Sea of Life with his flowers.[14]

Other appearancesEdit

He made a cameo in episode 6 of the Fate/Apocrypha anime along with the Knights of the Round Table in Kairi Sisigou's dream.

In the Prototype universe, Merlin's gender is female.


Though he counts as one among the top-ranking Casters, Merlin himself does not treat Magecraft as his forte. The reason being that he stumbles during incantations.[2]

Merlin is a formidable magus, said to be the most feared in the country.[6][15] He claims that he qualifies to be a Grand Caster and that he is a top tier servant on the level of Solomon. Bolstered by his Incubus heritage, Rin Tohsaka describes that being able to disguise Artoria's gender or "arrange for a child that should never have been born" should be extremely easy tasks.[4] The creation of Invisible Air is attributed to something he could have thought up for Artoria.[16]

He is a half-blood born from the union of a human and an incubus, he possesses the proof of the Highest Mage; Clairvoyance "the Eyes Which See through the World". Eyes able to see beyond while the person stands in place. From time immemorial, it is the power entrusted to lands by the gods and the power shamans needed to guard lives. However profound and capable of performing the strongest forms of Magecraft one's magic circuits may be, a mage who does not possess these "Eyes" shall not be given the title of the most supreme.[3] Possessing outstanding clairvoyance, in spite of having foreseen all about the collapse of the Round Table and Britain’s crisis, he left Britain without telling anything to King Arthur. There are many theories as for why Merlin never told King Arthur about her fate, but it is often said that it was because he is not biased towards individuals, instead caring only about fate.[2]

He is proficient in swordplay and is allegedly Artoria's swordsmanship instructor. He was shown in possession of Excalibur, saying that he prefers using it in combat over magic because he bites his tongue during long incantations and that "it's a lot easier to smack things around with a Holy Sword, you know?".

Independent ManifestationEdit

Merlin possesses Independent Manifestation, a Skill that permits the unsupported manifestation of oneself unto reality -- a capacity normally restricted to entities that fall within the irregular class of Beast.

Being entrapped within Avalon, Merlin should under no circumstances be summonable in the capacity of a Heroic Spirit; his Servant Profile in Fate/Grand Order states that irrelevant of the future that comes to pass, his death shall not occur, and he shall therefore not pass unto the Throne of Heroes as a Heroic Spirit capable of being summoned.

Being that serving a Master in the capacity of a Servant counts as one amongst his many interests and desires, however, for purposes of rendering his fantasies as reality, he has by personal effort obtained Independent Manifestation as a Skill. To put it in other words, he pretends as a Servant merely as a part of his hobby.[2]

By use of this skill, Merlin was able to be summoned by Gilgamesh in the 7th Singularity of Fate/Grand Order as an irregular Caster. When questioned as to how this was possible when he wasn't yet deceased, he claimed that it may have something to do with his connection with the Singularity; or the fact that the era of the summoning lies prior to his birth -- allowing for him to qualify as "not being alive."

In Chapter 16, after Merlin apparently dies following the defeat of the Conglomerate Divinity, Gorgon, Doctor Roman indicates that the Merlin that was travelling at your side was merely a projection, and that his primary manifestation within the era was occupied with the task of restraining the Goddess Tiamat within her slumber. He suggests that Merlin may have been killed in the process Tiamat's awakening.[17]

However, as of the end of the 7th Singularity, Merlin is revealed to be still alive -- taking advantage of the incineration of the Human Order to bypass his confinement within Avalon, and physically travelling to Babylonia to take part in the final battle against Tiamat.[14]


Merlin excels in the thaumaturgical discipline of Illusionism (幻術, genjutsu?), a Skill related to Mental Interference, which at a Rank of A permits interference with the psyche to the extent of introducing nightmares, and materializing illusions on the scale of a village within reality.[2]

Hero CreationEdit

The technique and art for artificially creating and rearing a "king". Merlin, who can be said to be King Arthur's true father, is already known as the best and foremost kingmaker in the world.


Taiki is the character designer for Merlin.[1][2] Kinoko Nasu is the scenario writer for her character.[1]

Comment from Illustrator "The feeling of a completely unknown age, and the impression of someone inhuman. For the sake of expressing that, I have him wear a white kimono. There is a sword set all hidden weapon-like in his cane, but the man himself doesn't really use it as a weapon, but more like playing it around as a toy-like gadget. Is what the image I'm going for." (Taiki)[1]


  1. 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 1.14 1.15 1.16 1.17 1.18 1.19 1.20 1.21 1.22 1.23 1.24 1.25 Fate/Grand Order material IV - Merlin, p.396-409
  2. 2.00 2.01 2.02 2.03 2.04 2.05 2.06 2.07 2.08 2.09 2.10 2.11 2.12 2.13 2.14 2.15 2.16 2.17 2.18 2.19 2.20 2.21 2.22 2.23 2.24 2.25 2.26 2.27 2.28 2.29 2.30 2.31 2.32 2.33 2.34 2.35
  3. 3.0 3.1 3.2 3.3 3.4 3.5 3.6 Garden of Avalon - Chapter 00: In the Flower Garden, p.004-013
  4. 4.0 4.1 4.2 4.3 Fate/stay night - Fate: Day 13 - Saber's contradiction
  5. Fate/stay night - Saber status profile
  6. 6.0 6.1 6.2 6.3 Fate/stay night - Fate: Day 11 - The king's memories
  7. 7.0 7.1
  8. Fate/hollow ataraxia - Sisters' crisis
  9. 9.0 9.1 9.2 9.3 Fate/stay night - Fate: Day 13 - The king's memories
  10. Fate/stay night - Fate: Day 12 - The king's memories
  11. Fate/stay night - Unlimited Blade Works: Day 10 - Night Training
  12. Fate/stay night - Last episode
  13. Garden of Avalon - Chapter 06: In the Flower Garden, p.103
  14. 14.0 14.1