Crystal (Wario: Master of Disguise)
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The Crystals are a set of key items from Wario: Master of Disguise. They are four bird-shaped statues which are found within purple treasure chests throughout Sneezemore Cave. During Episode 4, Wario needs to collect the crystals in order to open four doors which lead to where Carpaccio is guarding the second piece of the Wishstone. By placing each crystal in its appropriate slot near the doors, they open, allowing Wario to pass through and confront Carpaccio.
Despite the crystals being used to open the doors, Wario somehow re-closes them without removing the crystals in order to prevent Count Cannoli from following him.