Possible NPC doors to obtain the Tonsil Stone from, after setting foot in the Forbidden Woods:
- Central Yharnam - Every house with inhabitants inside.
- Cathedral Ward - First house on the right after exiting the room at the bottom of the pit (the same pit where the Abandoned Old Workshop door is found).
- Forbidden Woods - House near the dog cages.
- Hemwick Charnel Lane - House between first lamp and elevator.
When the Tonsil Stone is in the Hunter's inventory, a Lesser Amygdala, in the Cathedral Ward, will teleport the Hunter to the Lecture Building (1st floor). To reach the room with the Lesser Amygdala, take a left at the bottom of the first set of stairs after exiting the Grand Cathedral, in the Cathedral Ward. Continue past the area with the well and down a few ramps passing two Executioners. The second Executioner stands near the entrance to the room with the Lesser Amygdala.
Walking up to the door in the room will trigger a vortex animation and the Lesser Amygdala will grab the Hunter, followed by a cut scene. Note that no Blood Echoes will be lost and +2 Insight will be gained. From the point you spawn in the Lecture Building (1st floor), you will be unable to access the Nightmare of Mensis or the Lecture Building 2nd Floor. This can be used to reach the Nightmare Frontier faster for a player that wishes to PVP after starting a NG+.
- Players who miss the Tonsil Stone should not worry as Micolash's mummy is encountered at the end of Yahar'gul, they will materialize in the Lecture Building 2nd Floor, from which they can find a path to the floor below to explore the Nightmare Frontier.
- Tonsil Stone is actually given to the hunter by Patches the Spider, who at some point temporarily replaces every NPC hiding from the hunt in their houses.
- It looks like Amygdala's head, the description also refers to it.
- It is possible that the stone is made from siderite. Siderite is mentioned to be a rare stone that came from the "heavens", which has magnetic properties, and since the Tonsil Stone's description describes it as possibly being a meteorite with "gravitational force".