Zora Mask

The Zora's Mask is an item that appears in both Ocarina of Time and Majora's Mask.

Ocarina of Time
In Ocarina of Time, the mask is available for trade in The Happy Mask Shop. It serves no purpose other than to provoke different reactions from people Link talks to while wearing it. When shown to Princess Ruto, she will express her happiness that Link has become a Zora.

Majora's Mask
In Majora's Mask the mask allows Link to take on the body of the Zora guitarist, Mikau, becoming Zora Link. The transformation lends Link many abilities, including an impressive fighting style, two built-in Boomerangs, an Electric Barrier Shield that consumes magic power, and hightened agility in the water, including the ability to walk on the seafloor and swim at high speeds. The Zora Mask is one of four Transformation Masks in the game, the other three being the Deku Mask, the Goron Mask, and the Fierce Deity's Mask.

Link acquires the mask while visiting Great Bay. He notices a Zora floating in the water surrounded by gulls, near death. Once Link helps the Zora to shore, he tells Link that he is Mikau, guitarist for the famous Zora band The Indigo-Go's. He sings a song explaining that he was trying to help another band member recover eggs that were stolen from her by Gerudo Pirates, but was fatally injured in the process. Full of regret, he cannot die in peace, and asks someone to heal his soul. By playing the Song of Healing, Link can rest Mikau's soul, leaving behind the Zora Mask.