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One of the worlds that can be reached from the main doors ( the grey one on the upper left hand corner of the main hub)
It is basically a gigantic maze with NPC cogs going around ( they can be killed with the shovel if they get in your way)
So far, the only door that's been found in this world is a pink one that leads to a world with round objects moving in a continous pattern as they fall downwards, accompanied with the background music sounding like the ticking of a clock.
To get to that door, you have to go around the clock work maze and activate some switches ( their lights will go from red to blue when switched on) which will open a mechanical door that was blocking access to the pink door.