You cannot so much as scratch me while I'm inside this place. For those who call me a witch, I'll hand them befitting punishments.
~ Caster exchanging banter with Archer


Caster is the Caster-class Servant of Souichirou Kuzuki and the Master of another Servant, Assassin.

Her True Name is Medea, a princess tragically labeled as a witch. The daughter of King Colchis, she was made to fall in love with the hero Jason by Aphrodite, and she betrayed her father for him and supported him on his journeys. However, she was ultimately abandoned by her lover, and the actions she took afterwards are what cemented her reputation as a witch, murdering Jason's new bride and family before disappearing.

Powers and Stats

Tier: 9-B physically. 6-C with her magecraft

Name: Caster, Medea, the Witch of Betrayal

Origin: Fate/stay night

Age: Unknown

Gender: Female

Classification: Caster-class Servant

Powers and Abilities: Superhuman Physical Characteristics, Flight, Magecraft, Forcefield Creation, Fire Manipulation, Ice Manipulation, Electricity Manipulation, Mind Manipulation, Energy Absorption (Can absorb magical energy directly from the ground, humans, air and weaker spells), Can turn magical energy into matter and forge them into items, Information Analysis, Clairvoyance, BFR, Telepathy, Teleportation, Illusion Creation, Healing, Statistics Amplification, Summoning, Spatial Manipulation, can negate magic with Rule Breaker, Pocket Reality Manipulation (Given a lot of time and resources, Caster is capable constructing a "world" that is similar to a Reality Marble), Preparation, Limited Transmutation, Supernatural Luck, Minor Fate Manipulation (Servants with B-rank Luck or higher can change their own fates to evade inevitable outcomes such as having their hearts destroyed by Gáe Bolg) and Servant Physiology

Attack Potency: Wall level physically (Caster is not physically inclined and was easily overpowered by Rin Tohsaka while the latter was using Reinforcement. Nevertheless, even the weakest Servants can crush human skulls like eggshells with their fingertips). Island level with her magecraft (Can casually match one of Rin's gem with a single spell and easily nullified three of Rin's gems, which contained enough magical energy to completely destroy Ryuudou Temple and the Fuyuki Church. Took a few lives off of Berserker, and can potentially bypass Saber's A-rank Magic Resistance with her strongest spells. Her Prisma Illya counterpart, though significantly weaker, was going to completely destroy a replication of Fuyuki City had she not been stopped)

Speed: Massively Hypersonic (Can dodge attacks from Saber and Archer and keep up with them in combat to some extent. Managed to finish a spell off before Saber reached her master.)

Lifting Strength: Class 5 (Even possessing only an E Strength Parameter should make her comparable to Anastasia, who could lift and carry Ivan overhead)

Striking Strength: Wall Class (Even the weakest Servants are superior to humans, can easily cut off Shirou's arm with Rule Breaker)

Durability: Wall level (Was nearly killed by Rin in close combat). Island level with reinforcement (Survived a glancing hit from Caladbolg II, albeit with serious injuries). Higher with barriers (Can create barriers as strong as Berserker's skin).

Stamina: High.

Range: Melee range with Rule Breaker, Several Hundred meters to Kilometers with magecraft

Standard Equipment: Rule Breaker, and her staff.

Intelligence: True to her class, Caster is a prodigal magus from the Age of Gods that possesses mastery and power superior to any modern magus, as even the likes of Magicians like Aoko Aozaki would lose to her in a serious battle of magecraft. Roman claims that her skill is among the top five in the world, which is supported by the fact that she is considered a magus that is infinitely close to being a magician while not being one. As the "Witch of Betrayal", she is also a schemer by nature, forcing her foes into unfair situations to gain an advantage, and fights pragmatically and without restraint. She is also willing to commit horrific atrocities and conduct human experiments to improve her chances of victory, having experimented on or tortured Shirou in various Bad Ends. However, for all of her brilliance and mastery of magecraft, she is a terrible physical combatant and is prone to bouts of arrogance when she gains the upper hand such as claiming herself to be stronger than Saber or Berserker, which nearly led to her death in her battle against Archer and has even allowed Rin to overtake her with Reinforcement-boosted Chinese Martial Arts when she thought of their battle as one merely between two magus.

Weaknesses: Caster is rather arrogant, and is extremely weak in hand-to-hand combat. Several of her abilities (such as Soul Draining) require a great amount of prep time.

Notable Attacks/Techniques:

Noble Phantasms

  • Rule Breaker: All Spells Must Be Broken
  • Caster using Rule Breaker to break Saber and Shirou's contract in the visual novel
  • Caster using Rule Breaker in the Ufotable anime
  • Rule Breaker in Unlimited Codes
  • Rule Breaker in Fate/Grand Order

Magic's principles, divine providence, the principles of the world... All creation... I will send back everything to their origins.
Rule Breaker!

~ Caster using her Noble Phantasm

Rule Breaker: All Spells Must Be Broken: A jagged ritual dagger that encapsulates the legend of the Witch of Betrayal. It is useless in most combat scenarios, being only as useful as a knife in terms of killing power. It is an anti-magic Noble Phantasm that is capable of dispelling and destroying any kind of thaumaturgy, including contracts, enchantments, and magical creatures. There is a limit to the magic it can dispel, as Noble Phantasms are too powerful to be nullified by it. It is highly useful in the Holy Grail War, allowing Caster to break the contracts between Masters and Servants and take Servants for herself.


  • Rain of Light
  • Rain of Light in the Anime
  • Atlas
  • Caster attempting to block Caladbolg II with Argos
  • Caster leaving the battle with Trofa

Rain of Light (Machia Hecatia Graea): Caster's main offensive spell, which generates a number of magic circles that she aims at her targets and shoot rapid volleys of light beams at them. Each one of these beams is on the level of High-Thaumaturgy, having three times Shirou's maximum mana output and can annihilate Servants without a strong Magical Resistance with a direct hit. She normally restrains herself to just over a half dozen bolts at a time to avoid wasting mana, but the end result of her normal attacks resembles the aftermath of a bombing raid. When she has a much larger supply of mana, she can cover the sky in magical circles and demolish large swaths of land in seconds, unleashing powerful magical beams each with an A rank in power packed in them. Also, her strongest version of this spell is implied to be able to annihilate all of Fuyuki City in one use and can even bypass Saber's Magic Resistance, but this requires a great deal of magical energy and has a significant charging time.

Ατλας (Atlas): Caster locks down the space around a foe, immobilizing them. The primary use of this spell is to leave the target vulnerable to her Rain of Light attack. However, sufficiently high magic resistance and outside intervention can shatter the spell and render it useless.

Μαρδοξ (Argos): Caster can create barriers as strong as Berserker's God Hand.

Tροψα (Trofa): Caster is capable of long-range teleportation, teleporting herself and Kuzuki across all of Fuyuki City. Within the Ryuudou Temple, she can use this in combat, teleporting to dodge attacks and has even shown its use of teleporting others away.

Class Skills

Item Construction: A skill which measures one's ability to manufacture magical items. Caster does not use this ability much during the Fifth Holy Grail War but in side-materials and spin-offs, she is shown to be able to create very powerful magical items such as potions granting limited immortality and extremely effective good luck charms.

Territory Creation: A skill which quantifies one's ability to create a territory advantageous to them as a Magus. Caster's A-Rank in this skill allows her to create a "Temple", a territory that is superior to the "Workshop" used by most Magi. In this space, Caster can absorb magic from the leylines beneath her to provide her with a much larger mana supply along with the mana she drains from the residents of Fuyuki City. Also, she can replicate certain True Magics that were common in the Age of Gods, such as Teleportation, with ease.

Personal Skills

Argon Coin: The Golden Fleece of the winged ram Chrysomallos, that contains the legend "if thrown on the earth, a dragon will appear". Normally a Noble Phantasm, it has instead turned into a skill. When used properly, it can summon the Colchis Dragon. However, due to Medea lacking the knowledge to be able to summon Phantasmal Beasts, she instead uses it to heal herself.

High-Speed Divine Words: The power to activate Thaumaturgy without the use of Magic Circuits. The language of the Age of Gods, back when words played a heavy role in spellcasting. It is a power long lost by modern magi. Due to this ability, Caster can launch High-Thaumaturgy and Greater Rituals with a single word when modern magi would require several people working in tandem while chanting for several minutes.

Teachings of Circe: A skill that represents the era in which Princess Medea learned magecraft alongside the witch Circe, within the temple of the goddess Hecate. Since she learned magecraft as a Princess, she is not really a true witch.


Notable Victories:

Caster (Leonardo da Vinci) (Fate/Grand Order) da Vinci's profile (Note: Both bloodlusted)

Notable Losses:

Inconclusive Matches:

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