Fate/Apocrypha material - Encyclopedia: Subcategory Holy Grail Wars [Others said:
, p.154-155]
For instance, a subspecies Holy Grail War in Greece would create a struggle for a “catalyst of Heracles”, and the magi who managed to get it would win… In other words, the whole thing seems to go full circle and turn into a simple battle of magecraft between magi in the end. As a cute one-time divorcee magus said, “Rather, the whole idea of fighting that macho guy in his homeland is seriously ridiculous in the first place.”
After the use of Heracles was forbidden as a result of that, the next war turned into a competition over the catalyst of Achilles, and so there has never been a proper Holy Grail War held in Greece. There exist terrible tales of Holy Grail Wars like this.