Jalhalla

Jalhalla, also refered to as the Protector of the Seal, is the name given to the immense leader of the Poes in The Legend of Zelda: The Wind Waker that also serves as the Boss of the Earth Temple. Jalhalla is in fact composed of many smaller Poes. It is the creature Ganondorf used to kill Laruto, the previous Earth Sage.

Battle
When Link first encounter Jalhalla, he isn't formed and when the Poes present in the boss room notice Link, they jump into the mask found at the center of the room to become Jalhalla. In battle, Jalhalla is invincible to most attacks, can use his lantern to throw fireballs, breath fire or just blow air at Link, which can make him collide with the spikes found on all the walls of the boss room, additionally, if Link touch Jalhalla while he is intengible, the controls will be reversed for a few seconds. To damage Jalhalla, Link must use his Mirror Shield to deflect the light comming from the ceilling in the direction of jalhalla, which will makes him fall on the floor and make him material.

While Jalhalla is stuned on the floor, Link must lift him with his Power Bracelets and throw him on the spikes, which will make him burst into the smaller Poes, which can now be destroyed five at a time. Link must repeat this operation until their is no Poe remaining. This will effectively defeat the boss who leave behind a Heart Container and allows Medli to take Laruto's place as the new Earth Sage.

Figurine (Wind Waker)
"This gigantic ghost rules over all Poes. After reflecting light onto it with the Mirror Shield, you can lift it and throw it around."

Trivia

 * The Big Poe from The Legend of Zelda: Four Swords Adventures has some design similarities with Jalhalla.