The Fist of Gratia is probably one of the easiest weapons to obtain in Bloodborne: The Old Hunters. You simply have to defeat Ludwig in order to gain access to it. From the lamp at the Underground Corpse Pile, head to the underground cells where you’ll have to fight a church guard and an old man in a wheelchair. After you’ve disposed of them, look into one of the open cells to find the Fist of Gratia.
“A chunk of iron fitted with finger holes.
The hulking hunter woman Simple Gratia, ever hopeless when handling hunter firearms, preferred to knock the lights out of beasts with this hunk of iron, which incidentally caused heavy stagger.
Gratia was a fearsome hunter, and to onlookers, her unrelenting pummelling appeared oddly heroic. No wonder this weapon later assumed her name.”