The Deku Stick is the dried up stem of a dead Deku Baba. Their main use is to light them and to then use the fire for various purposes, although Link can also wield it like a weapon. They run off a limited time once lit, although this can be reversed and the Deku Stick saved for further use if put away before it completely burns.
 The Legend of Zelda: Ocarina of Time
In Ocarina of Time they can only be used by child link and has the same power as the Master Sword. They can be used for lighting things such as torches and spiderwebs as well as secrets like turning a butterfly into a Fairy, and can be found from defeated Deku Babas or purchased from a store. Although he originally holds ten of them, Link can find two upgrades for them: from a Business Scrub who resides in Lost Woods and from a bunch of Deku Scrubs in the Forest Stage by wearing the Skull Mask.
 The Legend of Zelda: Majora's Mask
The only person who can use the Deku Stick is Link. The purpose of a Deku Stick is to use it to burn various things. If you put a stick to a torch, and then you hit something flammable, like a spiderwed, it will burn down. If the Deku Stick touches water then the fire will go out. If you put a Deku Stick away before it burns up or breaks, it can be reused.
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