The prize obtained by the victor of the Holy Grail War—the "Holy Grail" sought by seven groups of magi and Heroic Spirits, said to possess the power to immediately grant any wish—was, in truth, merely a vessel that stored the souls of dead Servants and a necessary device for achieving the Third Magic by stabilizing the magical energy passage between the Great Holy Grail and the present world.
Up until the Third Holy Grail War, the Lesser Holy Grail had literally been a "cup," an object possessing the properties of a holy relic. However, because the Lesser Holy Grail was damaged during the fighting in the Third War and the ritual was terminated, it was later changed into a form capable of managing itself.
After the Third Holy Grail War, the Einzbern Family learned from the repeated destruction of the Grail in the previous wars and turned the Lesser Holy Grail into a freely mobile "Homunculus."
After the Fourth Holy Grail War ended, Zouken Matou implanted fragments of the Lesser Holy Grail into Sakura Matou's body.
"There's something I really don't understand. You weren't almost killed—you were killed, right? You can actually come back to life, Lin Yan."
Lin Yan did not answer his question directly. "You'll find out when the time comes."
Rin Tohsaka did not seem inclined to pursue the matter further, so she continued.
"Got it? Then let me explain a little more. I don't really understand what the Holy Grail War is either. The only thing I know for certain is that every few decades, seven Masters are chosen and each is given a Servant."
"I'm one of the people chosen as a Master. So I formed a contract with my Servant, and you formed one with Saber. Think of Servants as familiars granted by the