A Door

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A Door

Beyond the Fly Bend, you encounter a stone door, with a complex exposed locking mechanism, which appears to have had some parts removed from it.

Without a cog and a sprocket in your inventory:

Try as you might, you are unable to get the mechanism to work. You can go no further.

With a cog and a sprocket in your inventory:

A cog here, a sprocket there, and the mechanism clicks into place. The door swings open, and the way to the next chamber is clear.

Found in The Dark and Dank and Sinister Cave.