Its abilities are potent enough to heal critical and fatal wounds rapidly and restore the wielder's health. It allows for large missing portions of the body to be restored, the regeneration of destroyed organs, even including the heart, and minor injuries such as cuts to quickly heal. It differs from other Noble Phantasms used by Servants, as it is the genuine artifact that was excavated in Cornwall at the request of the Einzberns shortly before the Fourth Holy Grail War. It is used by Kiritsugu Emiya as the catalyst to summon Arturia as a Saber-class Servant and its existence is kept hidden from her. It is still in pristine condition after one thousand five hundred years, though it no longer functions without a connection to its original owner. It is later used to save the life of Shirou