Dungeon

Present in all Zelda games, the dungeons form the "underworld" of the worlds which Link visits and contain items and treasure to collect, enemies to overcome, and puzzles to be solved.

Purpose
The main reason for the existence of dungeons is to house a prize that Link must collect. Throughout the series these items have been different; Link collected fragments of the Triforce in the original LoZ, pendants and crystals in A Link to the Past, musical instruments in Link's Awakening, and other items throughout the other games. In Zelda 2 the goal was not to collect, but to return gems to magical statues in the dungeons.

Items
The dungeons that Link visits are home to valuable items and treasures for Link to collect, ranging from item upgrades to unique tools and weapons. Many of these items will prove to be essential to the completion of Link's goals. With the exception of Zelda 2, almost every dungeon that Link encounters contains a set of items usable only in that dungeon. These include a Dungeon Map, which displays the layout of the dungeon (but may still omit certain secret rooms.) The original use of the Compass was to display the location of the boss of the dungeon, but as the games moved into a 3D style it has come to also pinpoint hidden secrets within the dungeon. The Big Key is used to open specially locked doors (and sometimes chests.) It is sometimes called the Boss Key since its use usually signals that the boss fight is about to occur.