Dongorongo

Dongorongo is a Dodongo-like Boss in The Legend of Zelda: Phantom Hourglass. Link enters a room with sand surrounding the center platform. Link cannot cross the sand, as there is no bridge. However, a door opens in the back and a young Goron, named Gongoron, who is being held prisioner by Dongorongo comes out. The objective is to roll into Dongorongo's belly with Gongoron, turning him over. You must also be careful in what Link is doing, because he might get attacked by monsters while Gongoron is fighting. Then, Link must use a Bombchu to damage it by drawing a line into it's mouth. After doing this twice it appears to be defeated, as a bridge appears and Gongoron walks out of the room. However just as Link crosses the bridge, Dongorongo wakes up, and some of it's armor breaks revealing a weak spot. It attempts to inhale Link. This is your opportunity to throw a bomb into its mouth, and attack the weak point. Do this a few times, and the Heart Container, some more Sands of Time, and a pure metal, Crimsonine, are yours.

Trivia
Dongorongo is somewhat similar in appearance to the Pokemon Bastiodon and Heatran, from Pokemon Diamond and Pearl.