Rusty Key

The Rusty Key is a quest item in Pathologic 2. It is used to unlock the Haruspex's Lair.

Pathologic 2
If the Haruspex enters Isidor Burakh's House on Day 2, he will find the Rusty Key in a box in the backroom of the house. If he is unable to get to the house before Day 3, he will receive the Rusty Key directly from the Bachelor at Isidor's house.

After finding the Rusty Key, the Haruspex will receive updates to the mind-map suggesting that he either speak with Big Vlad or Vlad the Younger about it. It is unknown which Vlad he should speak to, as the note is simply signed with V.O. After talking to either Vlad, he will discover that the Rusty Key is actually from Vlad Jr.

Alpha Release
The Rusty Key was an item in the Alpha release of Pathologic 2. It was obtained from a box in Isidor Burakh's House for a quest on Day 2 of the Haruspex's route.

It was used to open the door into an abandoned room in the Factory, leading to the Haruspex's Lair. It has since been replaced with a note and key in the full release of the game.

The Alpha version of the Rusty Key is accessible only through Console Commands.