The Legend of Zelda: Ocarina of Time Master Quest is a reworked version of the original Ocarina of Time for the Nintendo 64. Master Quest contains largely the same content as the original Ocarina of Time, but with redesigned, more difficult dungeons akin to a Second Quest.
The most notable feature of Master Quest is that every dungeon in the game has been modified to increase the difficulty of the game. Each one features a different layout, changing the progression through the levels. Enemies are spread differently throughout the dungeons, and tougher enemies are encountered much earlier on than in Ocarina of Time. In addition, some Gold Skulltula locations in dungeons have been moved, and certain items that are optional in the original version are now mandatory to complete the game.