You are finally in Mutropolis! Open the door by showing the key to the console.
If you don't yet have the key, try to get into the crypt.
Unlike normal walkthroughs, in Nice Game Hints you can select just the puzzle you want hints for. Here are listed the puzzles for "Inside Mutropolis" in Mutropolis. The guide you choose only contains information about that puzzle, reducing possible spoilers for other puzzles.