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The Sail is an extremely important item in The Wind Waker, obtained early in the game.

Location and Uses
The Sail is purchased from Zunari on Windfall Island for the reasonably small price of 80 Rupees. The sail is the item which allows Link to catch prevailing winds, controlled by the Wind Waker, to sail from island to island. The sail can be set to either the X, Y or Z button on the GameCube controller, and it can only be used while onboard the King of Red Lions.

In, Link eventually gains the ability to sail faster, drastically reducing the time it takes to reach a destination. In addition, due to the altered controls, the Sail is now always mapped to the B Button while sailing, which is normally Link's sword when on foot. It is no longer treated as a normal item. The A Button is used to change the sailing speed.