Spanner

The Spanner (also known as the Wrench in later versions) is an item obtainable in Temple of Gloom.

How to obtain
Use the Spanner Mold in the molding room.

How to use
You can use it on the gears near the beginning of the level to gain access through some stairs on the left path in the beginning, ultimately creating a shortcut.

Trivia

 * Even without this item, you can still go through the level without it in most versions of the game.