Nightmare Key

, also known as Boss Room Keys, and , are recurring in .
==Location and uses==
Nightmare Keys, titled Boss Keys in other games, are one of the three standard dungeon items, the other two being the Compass and the Dungeon Map. They are generally harder to find than Small Keys and are used to open the big door leading to the Boss' chamber. Nightmare Keys can sometimes be used for purposes other than entering the Boss Room.
Nightmare Keys have a similar counterpart, Big Keys, which debuted shortly beforehand in . Other than unlocking a Boss Room, which is generally a Nightmare Key's sole distinct purpose, Big Keys can also unlock certain Treasure Chests.
==Mainline appearances==
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 open access to a Dungeon's Nightmare in .
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Boss Keys are always found in large Treasure Chests with yellow and blue designs in .
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The Boss Keys are functionally identical as in , and are found in the same type of chest. This iteration has a pattern of the key being found after every second Mini-Boss of each dungeon. The Boss Key does not remain with Link should he travel back in time. Instead, he must relocate the Treasure Chest containing the Boss Key to retrieve it once more. However, Link can directly warp to the boss's chamber one they have collected the remains.
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 are found in after a puzzle in and . They allow entry into Boss Rooms.
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The game has a naming discrepancy where they are named Big Keys in the English localization. Nightmare Keys function almost identically as in and and would continue for nearly all 3D Zelda games to come. The design of the key would be carried over in later installments, such as .
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Link must carry the Boss Key in his hands rather than in his inventory in , making him unable to attack and vulnerable to attacks.
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 must carry the Boss Key in his hands rather than in his inventory in , making him unable to attack and vulnerable to attacks. In some instances, Boss Keys are electrified, in which case Link must have Princess Zelda possess a Phantom to carry them on his behalf. Unlike in , Nightmare Keys are no longer obtained from Treasure Chests.
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==Other appearances==
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==Nomenclature==
==Gallery==
File:HW Boss Key.png| from 
File:HW Boss Key Icon.png| icon from 
==See Also==
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