Holy Grail War

Biodata

Rules and Structure

Masters and Servants

• A Master summons and contracts a Servant, supplying the magical energy needed for its manifestation and combat. Noble Phantasms can exhaust an ordinary Magus rapidly. 1 57
• Masters can view a contracted Servant's status panel, but a Servant's true name remains hidden unless voluntarily disclosed or compelled through a Command Seal. 1
• A Servant whose Master dies may remain active through Independent Action long enough to form a new contract. 68
• Servant auras can be sensed by other Servants and certain Grail-linked individuals, making them useful for recruitment but dangerous for concealment. 75
• A standard Holy Grail requires the souls of seven Servants to open a path to the Root. Normally, only one Servant may occupy a given class; the appearance of two Riders is treated as an abnormality. 56 73

Alliances and Intervention

• Alliances are temporary and strategic: the Three Great Families' rules require them to unite if an outsider is likely to win the war. 21
• The Church claims neutrality so long as the war does not endanger civilians or expose magecraft. It may act as a cleanup force and order the surviving participants to jointly eliminate a dangerous Servant. 10 13
• A Ruler-class Servant may be summoned to oversee a war; Jeanne d'Arc describes Ruler as ordinarily harmless in that supervisory role. 74 77

Secrecy

• Large-scale battles threaten the concealment of Mystery. During Caster's Sea Demon incident, Masters established broad Magic Barriers to evacuate civilians and prevent public exposure. 28
• The Church's formal involvement began during the Third Holy Grail War to contain supernatural leakage and erase remaining traces. 39

Grail System

Greater and Lesser Grails

• The Greater Holy Grail is a leyline-based system whose core gathers magical energy and enables wish granting. 54 98
• The Fuyuki system was created jointly by the Einzbern, Tohno, and Matou families. The Winter Saintess's role was central because she became the Grail's prize and core. 60 98
• Justeaze Lizrich von Einzbern became a living sacrifice to form the Fuyuki Greater Holy Grail's wish-granting core, which contains the Third Magic. 98
• A Lesser Holy Grail can serve as the vessel or heart associated with the Greater Grail. Mikaela attempted to replace Irisviel's failing core by becoming the Lesser Holy Grail himself. 48

Mana and Corruption

• A Holy Grail's stored mana can support Servant manifestation, powerful Noble Phantasms, and high-intensity battlefields. 56 156
• Incomplete Grails may provide insufficient modern magical energy, limiting the Servants they can sustain. 70
• The Fourth Fuyuki Grail became corrupted; its black-and-red mud descended from the mountain and caused a disaster until Mikaela destroyed the opening in the sky with Excalibur. 49
• Not every Grail is equivalent. The Lion King's Grail is described as the authentic Grail from legend, while Ramesses II's Grail was created by Goetia and functions primarily as a vast magic source. 146

Documented Conflicts

Fourth Holy Grail War

Opening Phase

Emiya Kiritsugu entered the Fuyuki war expecting to summon Artoria with the scabbard of the legendary Holy Sword. Instead, the ritual summoned Mikaela, a Saber with weak initial parameters and no Noble Phantasm listed on the status panel. 1

Mikaela and Kiritsugu approached the war as a conflict of intelligence, deception, and selective engagements. Mikaela avoided a decisive duel with Diarmuid so that the Church's anti-Caster mobilization could expose the other Masters and Servants. 16

Caster Mobilization

Caster's use of child sacrifices prompted the Church to order Masters and Servants to suspend their rivalries and eliminate him. 13

When Gilles de Rais summoned a colossal Sea Demon with the Book of the Sea God, the participating factions temporarily cooperated. Mikaela attacked with Oath of Judas, while Kayneth, Waver, and Irisviel established barriers to conceal the battle and disperse civilians. 28

Collapse

The Grail's corruption surfaced after Mikaela tried to serve as Irisviel's replacement Lesser Grail. The artificial heart rejected him, the Command Seal connection failed, and corrupted mud began flowing down the mountain. 48 49

Mikaela later manifested with the Lesser Holy Grail inside him and used Excalibur to destroy the hole through which the corrupted existence descended, ending the Fourth Holy Grail War. 49

Experimental Holy Grail Wars

• After Fuyuki, Matou Zouken distributed Grail fragments and information about the ritual to the Clock Tower, encouraging Magi to create their own Holy Grails. 54 112
• The Clock Tower's first constructed Grail was deliberately regarded as an experiment because it was crude despite containing a fragment of the Greater Holy Grail and some functions of the Third Magic. 56
• Most Magi were unwilling to risk their land and ley lines, since a conventional war can consume roughly half of a leyline's magical energy. Darnic accepted those risks in exchange for substantial benefits from other families. 56
• Darnic's Romanian conflict expanded beyond normal expectations: intelligence identified seven Servants summoned through the Greater Holy Grail, while Jeanne later characterized the confrontation as a seven-versus-seven Servant battle. 73 78
• The theft of the Romanian Grail core prevented a decisive winner and preserved the remaining Grail structure within the leylines, though stripped of its wish-granting function. 106

Notable Incidents

• Multiple Servants in one class — Two Riders appeared during the Clock Tower conflict, violating the expected one-Rider rule and confirming that the war's structure had become abnormal. 73
• Pre-war elimination — A Servant was eliminated before one war officially began, creating uncertainty among the remaining Masters and undermining Mikaela's confidence in his plans. 62
• Romanian Grail theft — Mikaela's faction infiltrated the Black faction's base while the opposing Servants were occupied, then took the Grail core and magical energy. 95 98
• Saber's factional takeover — In a later Fuyuki conflict, Saber acquired the Grail after all Masters vanished and enlisted Archer, Berserker, and Medusa against the remaining Servants. 119