Rusty Key

General

The Rusty Key is used to enter the Sewers. It is obtained from Gunther in a cutscene the morning after 60 items have been donated to the Museum. During the cutscene, Gunther greets the player at their front door, thanks them for their contributions to the museum, and gives them the Rusty Key. In Multiplayer, the host must speak with Gunther to get the key.

Where / when

Source
Gunther (60 Museum donations)
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