Silver Key

Silver Key, named Bronze in the original release, is a key item that appears in Final Fantasy Adventure and its remake, Adventures of Mana.

Final Fantasy Adventure/Adventures of Mana
While escorting Fuji to Wendel, Sumo decides to stop at the Kett Manor near the Marshes for the night. Upon staying overnight, the maiden mysteriously disappear during the hero's sleep. He hears other guests talking about a mysterious mirror kept in the depths of the sealed Marsh Cellar holding the power to reveal someone's true identity. He later finds the key to the cellar in the nearby Lizardmen's Nest and decides to venture into the dungeon.