Dark Mirror

The Dark Mirror makes its first and only appearance in Four Swords Adventures. According to the White Maiden, it is said to reveal the evil that lies within a person, bringing it to life. This is true, as the Dark Mirror used to spawn the Shadow Links which plague Hyrule and Link throughout the game.

History
When first mentioned by Dampé, the mirror is revealed to have sealed away a Dark Tribe a long time ago. The Mirror was then hidden away in a temple in the Forest of Light, in order to seal it away from the world.

Upon inspecting the Temple of Darkness, it comes to the Links' and the maidens' knowledge that the mirror had been stolen. They believe it to be Vaati's doing, but clues of the culprit, Deku Scrubs chanting the name Ganon, brings them to the desert, and their suspicion is confirmed by the Red Knight.

Upon arriving in The Dark Cloud of the Realm of the Heavens in the final clash against Shadow Link, Link and Princess Zelda finally manage to retrieve the mirror. This in turn leads to the end of Shadow Link's havoc in Hyrule.