Biggoron
Biggoron is, quite literally, a Big Goron.
Ocarina of Time
We first encounter Biggoron on the Death Mountain Summit. He complains that his eyes are suffering a great deal of pain because of the recent Death Mountain eruptions. He says that he will make Link a powerful blade (Biggoron Sword) if he can heal his eyes. To do this, Link must complete the Trading Quest.
Majora's Mask
Biggoron has been cursed, and turned invisible. He blows powerful gusts of wind to keep people away from Snowhead Temple. He was blocking Link's path! Link can only see Biggoron there if he uses the Lens of Truth. In order to get Biggoron out of the way, Goron Link must play the Goron's Lullaby. If Link plays this, Biggoron will fall asleep, and fall off the edge.
Minish Cap
After Link has defeated Vaati, he can have Biggoron nibble on his shield to make it the Mirror Shield.
Phantom Hourglass
The chief of Goron Island is named Biggoron. Although, he isn't as large as past Biggorons, but is actually the size of a normal Goron.