A word to describe the Holy Grail would be bored. It had grown bored of the established norms and servants being summoned. It's corrupting nature wanting more things to happen, and more unique entities to enter into the wars.
Another word to accurately describe the Grail would be malicious. These weren't going to just be good servants. These servants were going to raise absolute hell in the wars, whether for their masters or opponents. That will make the mortals squirm as they fight for a wish.
These two words were the search criteria for the grail as it extended its reach across universes, searching for 'heroic' lives. And it found the perfect ones that were both interesting and were sure to raise hell for those masters.
