The Whirligig Saw, or the oversized pizza cutter as I like to call it, is another one of the new fancy weapons you can acquire in Bloodborne: The Old Hunters. To get it, you’ll want to start your trek from the Nightmare Church lamp. Right next to the lamp, you’ll see a flight of stairs leading down. Be careful though; waiting for you near the bottom of those steps is a blood-addled hunter with a hammer that packs quite a punch. You’ll also find an NPC summoning sign here if you need it.
After taking out the hunter, drop back down to the river of blood where you’ll find a handful of crows waiting for you. Take care of the crows, pick up the blood vials sitting at the corner, and continue on your way. As you make your way down the river, be careful of an enemy dropping a boulder from above. You should be fine if you keep moving, so don’t worry too much about it. You’ll find a dead body sitting atop a stone tablet at the end of the river. Search the body to get your hands on the Whirligig Saw.
“A trick weapon crafted by the workshop heretics, the Powder Kegs, and weapon of choice of the Old Hunter Valtr, the Beast Eater.
This weapon pummels beasts in its mace form, but its true strength lies in its attached mechanical saws.
These discs, lined with serrated teeth,spin rapidly, trhashing the flesh of beasts into fine shreads.”