Deku Link

Deku Link is one of the forms Link turns into in. Link is transformed into this form at the beginning of the game, and can be later achieved by wearing the Deku Mask. It is one of four mask transformations in the game.

Transformation
After stumbling through the forest in pursuit of the Skull Kid, Link falls through a large hole leading to the parallel world of Termina. At the end of the hole, Link finds Skull Kid wearing the Majora's Mask. He eerily laughs and transforms Link into a Deku Scrub. However, the Happy Mask Salesman later finds Link and informs him that he can be returned to his original form if the instrument stolen from him, the Ocarina of Time, is retrieved. Link accepts the quest and explores the vast city of Clock Town over the course of three days and, after interacting with various townsfolk, manages to confront the Skull Kid atop the Clock Tower. He quickly uses a Bubble Blast to knock the ocarina out of Skull Kid's hands, scoops it up, and begins to play. To his surprise, simply being in Deku form causes Link's instrument to appear as the Pipes of Awakening. Undeterred, Link plays the "Song of Time" to travel back in time to the first day.

He presents the recovered instrument to the Happy Mask Salesman, who teaches Link the "Song of Healing". The magical properties of the song eases Link's soul, and he returns to his human form. The eradication of the curse causes the Deku Mask to materialize into the Deku Mask, granting Link the ability to transform at will into a Deku Scrub when worn. Link then starts his quest to find a way to retrieve the Majora's Mask that is manipulating the moon to crash into Termina.

Link's new form is required while he is exploring the spacious Southern Swamp, not only to hop across the toxic water, but also to infiltrate the gardens of Deku Palace, reveal the entrance to Woodfall Temple, and to explore and conquer the temple itself.

Origins
Deku Link is the incarnation of the Deku Butler's Son, who was turned into a tree while hunting for mushrooms in the forest, possibly as a curse by the possessed Skull Kid. It is heavily implied that the distorted tree was tortured in some way through Tatl commenting on how sad the tree looks and by the Deku Butler sorrowfully kneeling in front of his cursed son during the game's end credits.

Abilities
While in Deku Link form, Link gains many unique abilities which can be used to fight enemies and to solve puzzles. These abilities prove invaluable in several locations throughout Termina.

Water hopping
Deku Link is incapable of swimming, and thus instead travels on the surface of bodies of water through a series of hops. He can bounce up to five times on a water's surface, with the fifth bounce significantly higher than the previous four. If Deku Link falls into the water after the fifth bounce, he will sink and re-emerge back onto the ground. This ability prevents Deku Link from being damaged by toxic water or from being affected by the speed or direction of the current. This ability is primarily employed in areas with poisonous water, such as the Southern Swamp and the Woodfall Temple.

Deku Flower flight
By burrowing into a Deku Flower, Deku Link can launch himself into the air in brief flight and drop Deku Nuts onto enemies. The elevation and duration of the flight varies from flower to flower, though any flight can be extended if Deku Link passes through a powerful air stream. As well as granting Link access to previously inaccessible areas, launching from a Deku Flower is also a powerful attack move. This is necessary to defeat enemies such as Snappers, and can also be used to defeat the boss of the Woodfall Temple, Odolwa.

Spin Attack
By lightly tapping the A-Button while moving, Deku Link will twirl on one foot at an accelerated pace. This spin can stun enemies and break weak objects (such as pots), although it is rarely a powerful enough attack to kill an enemy.

Bubble Blast
This power is granted to Deku Link after he restores the body of the Great Fairy in North Clock Town. It allows Link to release powerful bubbles at the expense of draining magic power. This attack is useful to break airborne objects or to defeat flying enemies; the disadvantage is that the range is inefficient compared to that of arrows.

Deku Shield
Deku Link possesses a unique shield in the form of a large Deku Nut husk. It is similar to Goron Link's shield in that it renders Link immobile, but is also impervious to most attacks from any direction (excluding fire-based attacks). This defense is reminiscent of Young Link's attempt to use the Hylian Shield in.

Other abilities
Due to Deku Link's small frame, he is able to stand on lily pads without them sinking below him. This ability makes the exploration of poisonous waters in the Southern Swamp possible. However, this ability also makes it impossible for Deku Link to press down most floor switches. His small size also makes him too short to grab and climb onto most ledges.

As Deku Link is also made of wood, he is especially vulnerable to fire-based attacks. Mere contact with a flame of any sort will be typically enough to instantly knock him out, and he will reemerge from where he last entered the area.

Instrument
While in Deku form Link's ocarina takes the form of the Pipes of Awakening (also referred to as the Deku Pipes). This instrument is known for its high volume, and is required to play the "Sonata of Awakening" with maximum effect.

The Pipes of Awakening are primarily used to rise the Woodfall Temple from the swamp and grant access to the temple.

Super Smash Bros. Brawl
Deku Link appears as a sticker in Super Smash Bros. Brawl.

Trivia

 * When Deku Link opens a chest, he erroneously appears as right-handed.
 * Deku Link is the only one of Link's transformations in the game (excluding the Fierce Deity) that cannot press down a floor switch, making his Elegy of Emptiness statue unnecessary.