“A key effective on any locked door, chest, or bridge.” —In-game description, Shadow Dragon and Shin Monshō
The Master Key (万能鍵 Bannō kagi, lit. Omnipotent Key) is a key that first debuts in Fire Emblem: Shadow Dragon. Like its name suggests, the Master Key is one that is capable of indiscriminately manipulating all locks, regardless of whether they are imposed on Doors, Chests or bridges, a trait that is shared by the Lockpick. Master Keys are extremely rare items, but they are easily amongst the most useful that can possibly be acquired.