One of the seven classes of Heroic Spirit summoned by the Holy Grail to fulfill the ritual known as the Holy Grail War. Servants are the physical manifestation of legendary or mythical figures and draw power not only from their deeds in life but also from the reverence of people and the significance placed upon their deeds in the retelling of their life stories. They act as a special form of Familiar and obey certain rules devised as part of the ritual governing the Holy Grail War. In order to fulfill the ritual, the Servants must be sacrificed to provide power for the Holy Grail. Thus, the Holy Grail War began as a means of culling the Servants summoned for the ritual.
The seven classes of Servant are as follows: